Federalism-Based Limitations on Congressional Power: An Overview

Federalism-Based Limitations on
January 31, 2023
Congressional Power: An Overview
Kevin J. Hickey,
The U.S. Constitution establishes a system of dual sovereignty between the states and the federal
Coordinator
government. Although the Supremacy Clause of the Constitution designates federal law as
Legislative Attorney
supreme to state law, other provisions of the Constitution prohibit the national government from

enacting laws that either exceed federal power or improperly impinge upon state sovereignty.
Bryan L. Adkins
The various principles that delineate the proper boundaries between the powers of the federal and
Legislative Attorney
state governments are often referred to by the shorthand “federalism.” The Constitution’s

federalism-based restrictions on the national government’s power may inform Congress’s work
in numerous areas of law in which the states and the federal government share authority.
Whitney K. Novak
Legislative Attorney
The Constitution imposes federalism-based limitations on Congress in two basic ways. First, the

Constitution restricts Congress’s authority by the scope of the various powers it grants the federal
Jay B. Sykes
government. The Constitution explicitly grants Congress a set of carefully defined enumerated
Legislative Attorney
powers, while reserving most other legislative powers to the states, or to the people. As a result,

Congress may not enact any legislation that exceeds the limits of its enumerated powers.
However, Congress’s enumerated powers may authorize the federal government to enact

legislation that affects the scope of power exercised by the states. For instance, subject to certain
restrictions, Congress may use its taxing and spending powers to encourage states to undertake certain actions, even when
Congress lacks the constitutional authority to undertake those actions directly. Similarly, the Supreme Court has interpreted
the Constitution’s Commerce Clause to afford Congress authority to regulate purely intrastate economic activities that
substantially affect interstate commerce in the aggregate. Congress may also enact legislation necessary to implement
international treaties, even when Congress lacks authority in the area in the absence of the treaty. Under constitutional
amendments ratified shortly after the Civil War, Congress may in some cases directly regulate the states to prevent them from
depriving people of their constitutional rights. Finally, the Necessary and Proper Clause of the Constitution augments
Congress’s enumerated powers by empowering the federal government to enact laws that are appropriate and plainly adapted
to achieve a legitimate end within its enumerated powers.
Second, even when Congress has legislative authority to act in a particular area pursuant to its enumerated powers, its action
may still violate general federalism principles found elsewhere in the Constitution. The Supreme Court has recognized
federalism doctrines that affirmatively prohibit Congress from taking certain actions that intrude on state sovereignty, even if
otherwise authorized under an enumerated power. Although the specific textual source of these doctrines is not always clear,
the Court has often described them as based on the federal constitutional structure, as confirmed by the Tenth and Eleventh
Amendments. For example, the Supreme Court has held that the national government may not “commandeer” the states’
authority for its own purposes by forcing a state’s legislature or executive to implement federal commands. Similarly, the
principle of state sovereign immunity—which limits the circumstances in which a state may be sued in court without its
consent—constrains Congress’s ability to create federal causes of action against states or state officials. The Supreme Court
has also recognized a principle of “equal sovereignty” that may limit Congress’s ability to subject some states to unequal
regulatory burdens without sufficient justification.
Congressional Research Service


link to page 5 link to page 6 link to page 7 link to page 8 link to page 9 link to page 9 link to page 9 link to page 10 link to page 12 link to page 12 link to page 12 link to page 12 link to page 14 link to page 16 link to page 18 link to page 20 link to page 21 link to page 25 link to page 29 link to page 30 link to page 32 link to page 34 link to page 41 link to page 44 link to page 44 Federalism-Based Limitations on Congressional Power: An Overview

Contents
Conceptions of Federalism .............................................................................................................. 2
Limitations on Congress’s Enumerated Powers .............................................................................. 3
Spending Clause ........................................................................................................................ 4
Clear Notice ........................................................................................................................ 5
Relatedness ......................................................................................................................... 6
Independent Constitutional Bar .......................................................................................... 6
The “Anti-Coercion” Doctrine ............................................................................................ 6

Commerce Clause ..................................................................................................................... 7
Regulating the Channels of Interstate Commerce ............................................................... 9
Regulating the Instrumentalities of Interstate Commerce, or Persons or Things in

Interstate Commerce ........................................................................................................ 9
Regulating Activities that Substantially Affect Interstate Commerce ................................. 9
Regulating Inactivity .......................................................................................................... 11
Treaty Power ........................................................................................................................... 13
Congress’s Powers Under the Civil War Amendments ........................................................... 15
The State Action Requirement .......................................................................................... 17
“Congruence and Proportionality” for Remedial Legislation ........................................... 18
Necessary and Proper Clause .................................................................................................. 22
Federalism Limitations Based on the Tenth and Eleventh Amendments ...................................... 26
The Anticommandeering Doctrine .......................................................................................... 27
Anticommandeering and Preemption................................................................................ 29
The Eleventh Amendment and State Sovereign Immunity ..................................................... 31
Equal Sovereignty Doctrine .................................................................................................... 38
Conclusion ..................................................................................................................................... 41

Contacts
Author Information ........................................................................................................................ 41

Congressional Research Service

Federalism-Based Limitations on Congressional Power: An Overview

he Constitution establishes a “system of dual sovereignty between the States and the
Federal Government,”1 with each state having its own government, “endowed with all the
T functions essential to separate and independent existence.”2 Although the Constitution
grants the national government power over many areas,3 the Tenth Amendment reserves the
powers not delegated by the Constitution to the national government “to the States respectively,
or to the people.”4 Thus, under the Constitution’s structure, the powers granted to the national
government are “few and defined,” whereas the powers remaining in the states are “numerous
and indefinite.”5
When Congress acts pursuant to a valid grant of constitutional authority, the Supremacy Clause
makes its enactments the “supreme Law of the Land.”6 Valid federal laws therefore supersede
inconsistent or conflicting state laws, when Congress so intends.7 In this way, Congress has
authority to “impose its will on the States” when acting within its constitutional powers.8
However, the federal government may not exceed “the powers granted it under the Constitution,”9
and states “possess sovereignty concurrent with that of the Federal Government, subject only to
limitations imposed by the Supremacy Clause.”10 As a result, “States retain broad autonomy in
structuring their governments and pursuing legislative objectives.”11
The various principles that delineate the proper boundaries between the powers of the federal and
state governments are collectively known as “federalism.”12 The Supreme Court has described
federalism doctrines as serving several different purposes. Federalism is said to be a “check on
abuses of government power,” because “a healthy balance of power between the States and the
Federal Government will reduce the risk of tyranny and abuse from either front.”13 Although
federalism doctrines operate to “preserve[] the integrity, dignity, and residual sovereignty of the
States,”14 that is not the “end in itself.”15 Rather, the Supreme Court’s decisions maintain that

1 Gregory v. Ashcroft, 501 U.S. 452, 457 (1991).
2 Lane Cnty. v. Oregon, 74 U.S. (7 Wall.) 71, 76 (1869), superseded by statute as recognized in Leitch v. Dep’t of
Revenue, 9 Or. Tax 256 (1982).
3 See, e.g., U.S. CONST. art. I, § 8.
4 U.S. CONST. amend. X.
5 THE FEDERALIST NO. 45 (James Madison); accord Marbury v. Madison, 5 U.S. (1 Cranch) 137, 176 (1803).
6 See U.S. CONST. art. VI, cl. 2.
7 See generally Cong. Rsch. Serv., ArtVI.C2.1 Overview of Supremacy Clause, CONSTITUTION ANNOTATED,
https://constitution.congress.gov/browse/essay/artVI-C2-1/ALDE_00013395/ (last visited Nov. 11, 2022); CRS Report
R45825, Federal Preemption: A Legal Primer, by Jay B. Sykes and Nicole Vanatko.
8 Gregory v. Ashcroft, 501 U.S. 452, 460 (1991).
9 Id.
10 Tafflin v. Levitt, 493 U.S. 455, 458 (1990).
11 Shelby Cnty. v. Holder, 570 U.S. 529, 543 (2013).
12 See Federalism, BLACK’S LAW DICTIONARY (11th ed. 2019) (defining “federalism” as “the legal relationship and
distribution of power ... between the federal government and the state governments.”). In modern usage, the Supreme
Court has typically invoked “federalism” doctrines in cases involving solicitude for state sovereignty. See, e.g.,
Younger v. Harris, 401 U.S. 37, 44 (1971); Gregory, 501 U.S. at 458–60. There is a certain historical irony in this
usage in that, during the debates over the ratification of the Constitution, the Federalists (as opposed to the anti-
Federalists) were generally supporters of a stronger national government. See Akhil Reed Amar, Of Sovereignty and
Federalism
, 96 YALE L.J. 1425, 1426 n.9 (1987).
13 Gregory, 501 U.S. at 458.
14 Bond v. United States, 564 U.S. 211, 221 (2011).
15 New York v. United States, 505 U.S. 144, 181 (1992).
Congressional Research Service

1

link to page 10 link to page 30 link to page 30 Federalism-Based Limitations on Congressional Power: An Overview

federalism enhances freedom by securing to the people “the liberties that derive from the
diffusion of sovereign power.”16
Federalism has informed modern understandings of the limits on Congress’s authority in many
areas. For instance, the Supreme Court has identified limits on Congress’s enumerated powers,
such as its power to regulate interstate commerce under Article I, Section 8 of the Constitution.17
The Court has also recognized other federalism-based doctrines that constrain Congress’s power,
such as the anticommandeering doctrine—that is, the prohibition against the national government
demanding that a state use its own governmental system to implement federal commands.18 These
and other federalism-based limitations on Congress’s powers are important considerations
whenever Congress legislates, making federalism a “closely watched” and “ever-present” issue
for Congress.19
This report provides a broad overview of the various legal doctrines that inform the boundaries of
Congress’s authority vis-à-vis the states under the Constitution. The report begins by addressing
several general principles that undergird modern legal debates over federalism. It then discusses
the limitations on the exercise of Congress’s various enumerated powers, focusing on frequently
used powers such as Congress’s authority to appropriate and spend money, regulate interstate and
foreign commerce, implement international treaties, enforce the Civil War Amendments, and rely
on the Necessary and Proper Clause. The report next reviews federalism doctrines that
affirmatively prohibit Congress from taking certain actions that intrude on state sovereignty, even
if otherwise authorized under an enumerated power. These doctrines—such as the
anticommandeering doctrine, state sovereign immunity, and the equal sovereignty doctrine—may
constrain Congress’s power to act even when Congress has legislative authority in a particular
area.
Conceptions of Federalism
Before discussing the various federalism-based limits on Congress’s powers, it is helpful to note
the debate over how these limitations are enforced, and by whom. Broadly speaking, the Supreme
Court in the modern era has advanced two “competing conceptions of federalism.”20
Exemplifying one viewpoint is the Court’s 1985 decision in Garcia v. San Antonio Metropolitan
Transit Authority
, which held that the Constitution does not insulate state governments from the
reach of generally applicable federal laws enacted under the Commerce Clause.21 Garcia
reasoned that the “principal and basic limit” on Congress’s powers vis-à-vis the states is “the
built-in restraints that our system provides through state participation in federal governmental
action.”22 Put another way, Garcia concluded that “political processes” (i.e., Congress and the

16 Id. (quoting Coleman v. Thompson, 501 U.S. 722, 759 (Blackmun, J., dissenting)).
17 See, e.g., United States v. Lopez, 514 U.S. 549, 557 (1995) (noting that the commerce power is “subject to outer
limits”); NFIB v. Sebelius, 567 U.S. 519, 558 (2012) (opinion of Roberts, C.J.). See also infra “Commerce Clause.”
18 See, e.g., Printz v. United States, 521 U.S. 898, 935 (1997) (“The Federal Government may neither issue directives
requiring the States to address particular problems, nor command the States’ officers, or those of their political
subdivisions, to administer or enforce a federal regulatory program.”). See also infra “The Anticommandeering
Doctrine.”

19 See CHRISTOPHER P. BANKS & JOHN C. BLAKEMAN, THE U.S. SUPREME COURT AND NEW FEDERALISM: FROM THE
REHNQUIST TO THE ROBERTS COURT 2 (2012).
20 Erwin Chemerinsky, The Assumptions of Federalism, 58 STAN. L. REV. 1763, 1768 (2006).
21 See 469 U.S. 528, 547 (1985).
22 Id. at 556.
Congressional Research Service

2

link to page 5 Federalism-Based Limitations on Congressional Power: An Overview

President’s discretion) and not the courts, would be the primary means to enforce the federalism-
based limits on Congress’s powers.23
The political-process conception of federalism embraced in Garcia has largely been supplanted in
a series of Supreme Court decisions beginning in the 1990s and continuing to the present.24 The
currently prevailing view is that the judiciary has an important role in safeguarding state
governments from federal overreach.25 For instance, in 1995, the Court in United States v. Lopez
struck down a federal law that forbade possessing a gun within 1,000 feet of a school, holding
that the law exceeded Congress’s powers under the Commerce Clause.26 In so concluding, Lopez
described the federalism-based limitations on Congress’s commerce power as limits that ‘“the
Court has ample power’ to enforce.”27
Current doctrine has thus recognized that the judiciary can police the limits of Congress’s powers
vis-à-vis the states. Nonetheless, as Justice Anthony Kennedy expressed in his concurrence in
Lopez, the political branches continue to have a central role in recognizing the limits on
Congress’s powers in areas potentially intruding on the sovereignty of state governments:
Whatever the judicial role, it is axiomatic that Congress does have substantial discretion
and control over the federal balance. For these reasons, it would be mistaken and
mischievous for the political branches to forget that the sworn obligation to preserve and
protect the Constitution in maintaining the federal balance is their own in the first and
primary instance.... The political branches of the Government must fulfill this grave
constitutional obligation if democratic liberty and the federalism that secures it are to
endure.28
The federalism-based limits on Congress’s power discussed in this report thus are more than just
factors for Congress to consider in drafting legislation to ensure that a court does not invalidate it
on federalism grounds. Federalism may also be an important background principle for legislators
to consider to ensure that the political process respects and maintains the appropriate
constitutional balance between state and federal authority.29
Limitations on Congress’s Enumerated Powers
The Constitution confers certain enumerated powers upon Congress,30 many of which are not
specifically discussed in this report. Some of Congress’s powers—such as those under the

23 Id.
24 See generally Cong. Rsch. Serv., Amdt10.4.1 Modern Tenth Amendment Jurisprudence Generally, CONSTITUTION
ANNOTATED, https://constitution.congress.gov/browse/essay/amdt10-4-1/ALDE_00013626/ (last visited Nov. 11,
2022).
25 See Chemerinsky, supra note 20, at 1768–69 (describing the shifting views on the Court concerning federalism).
26 See 514 U.S. 549, 552 (1995); see also New York v. United States, 505 U.S. 144, 149 (1992).
27 Lopez, 514 U.S. at 557 (quoting Maryland v. Wirtz, 392 U.S. 183, 196 (1968), overruled on other grounds by Nat’l
League of Cities v. Usery, 426 U.S. 833 (1976), overruled by Garcia v. San Antonio Metro. Transit Auth., 469 U.S.
528 (1985)).
28 Id. at 577–78.
29 Id.
30 See generally U.S. CONST. art. I, § 8.
Congressional Research Service

3

link to page 7 link to page 10 link to page 16 link to page 18 link to page 25 Federalism-Based Limitations on Congressional Power: An Overview

Spending Clause,31 the Commerce Clause,32 the Treaty Power,33 the Civil War Amendments,34 and
the Necessary and Proper Clause35—are particularly significant in delineating the allocation of
power between the federal government and the states. The sections below discuss the limitations
the Constitution imposes on Congress’s exercise of those particular powers.
Spending Clause
The Spending Clause empowers Congress to “lay and collect Taxes, Duties, Imposts, and Excises,
to pay the Debts and provide for the common Defence and general Welfare of the United
States.”36 The breadth of the Spending Clause was the subject of much debate for the first 150
years of the nation’s history. Under one view—favored by James Madison—Congress’s Spending
Clause powers were narrow. Madison contended that those authorities extended only to spending
in connection with Congress’s other enumerated powers, such as the power to regulate interstate
commerce.37 In contrast, others—most prominently, Alexander Hamilton—viewed the Spending
Clause as conferring an independent power for Congress to raise and spend money to promote the
national welfare.38
The Hamiltonian position ultimately prevailed. In 1936, the Supreme Court held in United States
v. Butler
that Congress’s Spending Clause authority is not limited to expenditures carrying out its
other enumerated powers.39 The Court thus recognized that Congress has broad constitutional
authority to spend money in pursuit of its goals.
Although the Supreme Court has rejected the narrow Madisonian view of the Spending Clause, it
has acknowledged other limitations on Congress’s spending power. One limitation has proved to
be quite minimal in practice. Based on the text of the Spending Clause, the Court has explained
that Congress’s spending power is limited to expenditures in pursuit of the “general Welfare.”40
Despite articulating this theoretical limitation, the Court has never deployed it to invalidate a
federal expenditure.41 Rather, the Court has explained that courts should generally defer to

31 See infra “Spending Clause.”
32 See infra “Commerce Clause.”
33 See infra “Treaty Power.”
34 See infra “Congress’s Powers Under the Civil War Amendments.”
35 See infra “Necessary and Proper Clause.”
36 U.S. CONST. art. I, § 8, cl. 1. Because the Clause empowers Congress to “lay and collect Taxes,” the Spending Clause
is sometimes called the “Taxing and Spending Clause.” See, e.g., David S. Schwartz, A Question Perpetually Arising:
Implied Powers, Capable Federalism, and the Limits of Enumerationism
, 59 ARIZ. L. REV. 573, 581 (2017). Congress’s
power to tax may be limited by other provisions of the Constitution that are not directly related to principles of
federalism. See United States v. Kahriger, 345 U.S. 22, 28 (1953) (“[T]he constitutional restraints on taxing are few.
Congress cannot tax exports, and it must impose direct taxes by the rule of apportionment, and indirect taxes by the rule
of uniformity.” (internal citations and quotations omitted)), overruled in part on other grounds by Marchetti v. United
States, 390 U.S. 39, 54 (1968).
37 See 30 ANNALS OF CONG. 1059–62 (1817) (Madison Veto Message); Letter from James Madison to Andrew
Stevenson (Nov. 27, 1830), reprinted in 2 THE FOUNDERS’ CONSTITUTION 453, 456 (Philip B. Kurland & Ralph Lerner
eds., 1987).
38 Alexander Hamilton, Report on Manufacturers (Dec. 5, 1791), reprinted in 2 THE FOUNDERS’ CONSTITUTION 453,
456 (Philip B. Kurland & Ralph Lerner eds., 1987).
39 297 U.S. 1, 66 (1936).
40 See U.S. CONST. art. I, § 8, cl. 1.
41 NFIB v. Sebelius, 567 U.S. 519, 674 (2012) (Scalia, J., dissenting).
Congressional Research Service

4

link to page 8 Federalism-Based Limitations on Congressional Power: An Overview

Congress’s assessment of the “general welfare” and only strike down Spending Clause legislation
when it represents “a display of arbitrary power.”42
Other limitations on the Spending Clause have proven more consequential. These limits—several
of which are grounded in the Tenth Amendment—constrain Congress’s ability to impose
conditions on the receipt of federal funds by states or localities. Specifically, if Congress attaches
conditions to federal funding for states and localities, those conditions must be unambiguous,
related to the purpose of the relevant spending, consistent with other constitutional provisions,
and noncoercive.43 Each of these limitations on Congress’s spending power is discussed below.
Clear Notice
The Supreme Court has held that, if Congress intends to place conditions on the receipt of federal
funds by states or localities, it must do so “unambiguously.”44 The Court announced this “clear
notice” rule in 1981 in Pennhurst State School & Hospital v. Halderman, which involved a statute
that funded state services for the developmentally disabled.45 By accepting the funds, states were
required to make assurances that they would protect the “rights” of disabled persons “consistent
with” the statute’s “findings” section.46 That section provided that developmentally disabled
persons “have a right to appropriate treatment,” and that such treatment “should be provided in
the setting that is least restrictive of ... personal liberty.”47
In Pennhurst, the Supreme Court held that states were not required to abide by these findings as a
condition of receiving the relevant federal funds. In reaching this conclusion, the Court likened
Spending Clause legislation to contracts between the federal government and the states.48 If states
are to “voluntarily and knowingly” accept such contracts, the Court explained, Congress must
clearly articulate their terms.49 The Court ultimately determined that the statute at issue in
Pennhurst did not unambiguously condition receipt of the relevant funds on compliance with its
“findings” section.50 As a result, recipients of those funds were not required to provide disabled
persons with “appropriate treatment” in a setting that was “least restrictive” of their personal
liberties.51
Pennhurst suggested—and later cases have confirmed—that the clear-notice rule is a
constitutional requirement and not merely a principle of statutory interpretation.52

42 Helvering v. Davis, 301 U.S. 619, 640 (1937) (holding that scheme of benefits under the Social Security Act was
valid exercise of Congress’s power to tax and spend in aid of the general welfare).
43 For a more detailed overview of these limits, see CRS Report R46827, Funding Conditions: Constitutional Limits on
Congress’s Spending Power
, by Victoria L. Killion.
44 Pennhurst State Sch. & Hosp. v. Halderman, 451 U.S. 1, 17 (1981).
45 Id.
46 Id. at 12–14.
47 Id. at 13.
48 Id. at 18–27.
49 Id. at 17.
50 Id. at 18–27.
51 Id.
52 See id. at 17; CRS Report R46827, supra note 43, at 7.
Congressional Research Service

5

Federalism-Based Limitations on Congressional Power: An Overview

Relatedness
The Supreme Court has also stated that conditions on federal funds must relate to the purpose of
the relevant spending.53 However, this “relatedness” requirement is not demanding. The Supreme
Court has never invalidated a spending condition on relatedness grounds,54 and lower courts have
generally applied deferential standards in evaluating relatedness challenges. The Ninth Circuit,55
for example, has explained that a funding condition must bear only “some relationship” to the
purpose of federal spending—a requirement that it described as a “low bar.”56 The Tenth Circuit
has similarly described the required relationship as “one of reasonableness or minimum
rationality.”57
The relatedness limitation is not strict, but it is not wholly toothless. During the Trump
Administration, two federal district courts relied on the relatedness requirement to invalidate
conditions on the receipt of certain Department of Justice grants.58 The grants at issue supported
state and local criminal-justice initiatives, whereas the conditions required recipients to cooperate
with federal immigration-enforcement efforts in various ways. Two district courts concluded that
immigration enforcement was not sufficiently related to the relevant criminal-justice initiatives,
and struck down certain conditions on the grants for that reason (among others).59 (One of those
decisions was later affirmed on other grounds.)60 These opinions suggest that the relatedness
limitation may impose a meaningful constraint in certain cases.
Independent Constitutional Bar
Constitutional provisions other than the Spending Clause can also provide an “independent bar”
to conditional grants of federal funds.61 For example, the Supreme Court has explained that
Congress cannot use its Spending Clause authority to induce states to engage in unconstitutional
activities, such as discriminating on the basis of race or inflicting cruel and unusual punishment.62
The “Anti-Coercion” Doctrine
Finally, the Supreme Court has explained that conditions on federal funding cannot be unduly
coercive. This limitation, according to the Court, is “critical to ensuring that Spending Clause
legislation does not undermine the status of the States as independent sovereigns in our federal

53 South Dakota v. Dole, 483 U.S. 203, 207 (1987).
54 See City of Los Angeles v. Barr, 929 F.3d 1163, 1175 (9th Cir. 2019).
55 This report periodically references decisions by federal appellate courts of various regional circuits. For purposes of
brevity, references to a particular circuit in the body of this report (e.g., the Ninth Circuit) refer to the U.S. Court of
Appeals for that particular circuit.
56 Barr, 929 F.3d at 1175 (citation omitted).
57 Kansas v. United States, 214 F.3d 1196, 1199 (10th Cir. 2000).
58 Colorado v. Dep’t of Just., 455 F. Supp. 3d 1034, 1055 (D. Colo. 2020); City & Cnty. of San Francisco v. Sessions,
349 F. Supp. 3d 924, 961 (N.D. Cal. 2018), affirmed in part, vacated in part by City & Cnty. of San Francisco v. Barr,
965 F.3d 753 (9th Cir. 2020); see also City of Philadelphia v. Sessions, 280 F. Supp. 3d 579, 644 (E.D. Pa. 2017)
(explaining that the relatedness issue was a “close question” in litigation concerning immigration-related conditions on
the relevant grants).
59 Colorado, 455 F. Supp. 3d at 1055; City & Cnty. of San Francisco, 349 F. Supp. 3d at 961.
60 City & Cnty. of San Francisco, 965 F.3d 753.
61 South Dakota v. Dole, 483 U.S. 203, 208 (1987).
62 Id. at 210.
Congressional Research Service

6

link to page 30 Federalism-Based Limitations on Congressional Power: An Overview

system,”63 as “the Constitution has never been understood to confer upon Congress the ability to
require the States to govern according to Congress’ instructions.”64 In this sense, the anti-coercion
doctrine can be understood as the application of the anticommandeering principle to the Spending
Clause context.65
In its 1987 decision in South Dakota v. Dole, the Supreme Court recognized that certain financial
inducements “might be so coercive as to pass the point at which pressure turns into
compulsion.”66 In Dole, the Court rejected a challenge to a law that would have stripped states of
certain federal highway funds if they refused to adopt the national minimum drinking age.67 The
Court determined that the law—which would cost noncompliant states 5% of otherwise-
obtainable highway funds—presented states with “relatively mild encouragement,” but did not
unconstitutionally coerce them into accepting federal policy.68
By contrast, the Court held that a federal law crossed the line between acceptable encouragement
and impermissible coercion in its 2012 decision in NFIB v. Sebelius.69 There, the Court held that
Congress violated the anti-coercion doctrine by withholding all Medicaid funding from states that
did not accept the Affordable Care Act’s Medicaid expansion.70 In a plurality opinion, Chief
Justice Roberts highlighted the fact that Medicaid had become a “substantial part” of many state
budgets,71 observing that Medicaid constituted more than 10% of most states’ revenue, whereas
the highway funds at issue in Dole represented less than 0.5% of South Dakota’s budget.72 By
threatening to strip states of such significant sums, Chief Justice Roberts explained, the condition
effectively operated as a “gun to the head” that unconstitutionally coerced states into accepting
the Medicaid expansion.73
Commerce Clause
Perhaps the most consequential of Congress’s enumerated powers is the Commerce Clause,74
which grants Congress the power “[t]o regulate Commerce with foreign Nations, and among the
several States, and with the Indian Tribes.”75 The Commerce Clause thereby authorizes Congress
to regulate a wide range of economic and social activities.76 The Supreme Court’s views on the

63 NFIB v. Sebelius, 567 U.S. 519, 577 (2012) (opinion of Roberts, C.J.)
64 Id. (quoting New York v. United States, 505 U.S. 144, 162 (1992).
65 See infra “The Anticommandeering Doctrine.”
66 Dole, 483 U.S. at 211 (internal quotation marks and citation omitted).
67 Id.
68 Id.
69 567 U.S. 519 (2012).
70 Id. at 575–89 (Roberts, C.J.); id. at 671–89 (Scalia, J., dissenting).
71 Id. at 542, 580–82 (Roberts, C.J.).
72 Id.
73 Id. at 581 (Roberts, C.J.).
74 See ERWIN CHEMERINSKY, CONSTITUTIONAL LAW: PRINCIPLES AND POLICIES 174 (1997) (arguing that, of the eighteen
clauses enumerated in Article I, Section 8 detailing Congress’s powers, “none is more important” than the Commerce
Clause); EDWARD S. CORWIN, THE CONSTITUTION AND WHAT IT MEANS TODAY 54 (13th ed. 1973) (“The commerce
clause comprises, however, not only the direct source of the most important peace-time powers of the National
Government; it is also, except for the Due Process of Law Clause of Amendment XIV, the most important basis for
judicial review in limitation of State power.”).
75 U.S. CONST. art. I, § 8, cl. 3.
76 See, e.g., Paul Boudreaux, A Case for Recognizing Unenumerated Powers of Congress, 9 N.Y.U. J. LEGIS. & PUB.
POL’Y 551, 555 (2006) (“Th[e] authority to regulate interstate commerce ... forms the constitutional basis for nearly all
Congressional Research Service

7

link to page 10 Federalism-Based Limitations on Congressional Power: An Overview

breadth of Congress’s commerce powers have varied throughout the nation’s history.77 In the late
19th century and early 20th century, the Court embraced a relatively narrow view of the Commerce
Clause, holding that Congress lacked the constitutional authority to regulate subjects such as
manufacturing78 or child labor.79 Beginning in 1937 until nearly the end of the 20th century, by
contrast, the Court adopted a seemingly boundless view of the Commerce Clause, going so far in
the 1942 case of Wickard v. Filburn to hold that Congress may validly regulate the production of
homegrown wheat intended wholly for personal consumption.80 The Wickard Court reasoned that
the Commerce Clause authorizes Congress to regulate activities having a substantial aggregate
effect on interstate commerce and that Congress reasonably concluded homegrown wheat had
such an effect.81 In response to this shift in the Court’s Commerce Clause jurisprudence,
Congress invoked its commerce powers as the constitutional basis for federal legislation on many
subjects throughout the 20th century,82 including criminal,83 civil rights,84 and environmental
statutes.85
In a series of rulings beginning in the mid-1990s, the Court held that certain federal legislation
exceeded Congress’s commerce power.86 The Supreme Court’s 1995 opinion in United States v.
Lopez
sets forth the modern test for determining whether a federal statute exceeds the scope of
Congress’s Commerce Clause authority.87 The Court held in Lopez that there are “three broad
categories of activity that Congress may regulate under its commerce power.”88 These are
(1) “channels of interstate commerce”; (2) “instrumentalities of interstate commerce, or persons
or things in interstate commerce”; and (3) “activities that substantially affect interstate
commerce.”89

modern social legislation, from the civil rights laws, to employment statutes, to environmental legislation.”).
77 NFIB v. Sebelius, 567 U.S. 519, 549 (2012) (Roberts, C.J.) (“The path of our Commerce Clause decisions has not
always run smooth.”).
78 See United States v. E.C. Knight Co., 156 U.S. 1, 13–14 (1895).
79 See Hammer v. Dagenhart, 247 U.S. 251, 276 (1918), overruled by United States v. Darby, 312 U.S. 100, 117
(1941).
80 317 U.S. 111, 127–29 (1942).
81 Id. at 125, 127–29.
82 See Boudreaux, supra note 76, at 556.
83 See O’Rourke v. City of Norman, 875 F.2d 1465, 1469 (10th Cir. 1989) (“[F]or most federal criminal laws in the past
century, the jurisdictional basis is the Commerce Clause.... ”).
84 See Stephen R. McAllister, Is There a Judicially Enforceable Limit to Congressional Power Under the Commerce
Clause?
, 44 U. KAN. L. REV. 217, 224–25 (1996) (“[T]he Commerce Clause, not the Fourteenth Amendment, was
deemed the primary source of constitutional authority supporting the major civil rights statutes of the 1960s.”).
85 See Blake Hudson, Reconstituting Land-Use Federalism to Address Transitory and Perpetual Disasters: The
Bimodal Federalism Framework
, 2011 B.Y.U. L. REV. 1991, 2044 (2011) (“In the United States, the Commerce Clause
is the primary constitutional provision under which most environmental legislation is passed.”).
86 See, e.g., NFIB v. Sebelius, 567 U.S. 519, 558 (2012) (Roberts, C.J.) & id. at 649–50 (Scalia, Kennedy, Thomas, &
Alito, JJ., dissenting) (collectively concluding that a requirement that an individual purchase health insurance exceeded
Congress’s authority under the Commerce Clause); United States v. Morrison, 529 U.S. 598, 617 (2000) (holding that
Congress lacked authority under the Commerce Clause to create a federal civil remedy for the victims of gender-
motivated violence); United States v. Lopez, 514 U.S. 549, 558 (1995) (invalidating a law prohibiting possessing a gun
within 1,000 feet of a school).
87 See Lopez, 514 U.S. at 558.
88 Id. at 559.
89 Id. at 558–59.
Congressional Research Service

8

Federalism-Based Limitations on Congressional Power: An Overview

Regulating the Channels of Interstate Commerce
Channels of interstate commerce are “the interstate transportation routes through which persons
and goods move,”90 such as the nation’s highways, railroads, navigable waterways, and
airspace.91 Congress’s authority to regulate the channels of interstate commerce is not confined to
activities that have an economic purpose. Instead, Congress has authority “to keep the channels of
interstate commerce free from immoral and injurious uses”92 and may “exclude from the
commerce articles whose use in the states for which they are destined it may conceive to be
injurious to the public health, morals or welfare.”93 Applying this principle, the Court has upheld
Congress’s authority to prohibit the interstate shipment of stolen goods or kidnapped persons;94
the interstate shipment of goods produced without minimum-wage and maximum-hour
protections;95 the interstate transportation of a woman or girl for prostitution;96 and the interstate
mailing or transportation of lottery tickets.97
Regulating the Instrumentalities of Interstate Commerce, or Persons or Things
in Interstate Commerce

The instrumentalities of interstate commerce refer to the means of interstate commerce, such as
an airplane or train, whereas the persons or things in interstate commerce refer to the persons or
things transported by the instrumentalities among the states.98 The Supreme Court has recognized
that Congress possesses the authority to address threats to the instrumentalities of commerce or to
persons or things in commerce even if those threats “come only from intrastate activities.”99 The
Court has thus upheld federal safety regulations as applied to trains and railcars travelling
intrastate on a railroad line because the “absence of appropriate safety appliances” from the
intrastate trains and cars was a threat to those moving in interstate commerce.100 The Court has
likewise observed that Congress may validly criminalize the destruction of an aircraft or the theft
of interstate shipments.101
Regulating Activities that Substantially Affect Interstate Commerce
Congress possesses the constitutional authority to regulate “activities that substantially affect
interstate commerce.”102 This category, which one court described as the “most unsettled” and

90 Morrison, 529 U.S. at 613 n.5 (quoting United States v. Lankford, 196 F.3d 563, 571–72 (5th Cir.1999)).
91 See, e.g., United States v. Ballinger, 395 F.3d 1218, 1225–26 (11th Cir. 2005).
92 Heart of Atlanta Motel, Inc. v. United States, 379 U.S. 241, 256 (1964).
93 United States v. Darby, 312 U.S. 100, 114 (1941).
94 See Perez v. United States, 402 U.S. 146, 150 (1971).
95 Darby, 312 U.S. at 112–14.
96 Caminetti v. United States, 242 U.S. 470, 491–92 (1917).
97 Champion v. Ames (The Lottery Case), 188 U.S. 321, 354–55 (1903).
98 See, e.g., United States v. Patton, 451 F.3d 615, 621–22 (10th Cir. 2006); United States v. Bishop, 66 F.3d 569, 588
(3d Cir. 1995), as amended (Sept. 29, 1995).
99 Lopez, 514 U.S. at 558 (emphasis added).
100 S. Ry. Co. v. United States, 222 U.S. 20, 27 (1911); see also Hous., E. & W. Tex. Ry. Co. v. United States (The
Shreveport Rate Cases
), 234 U.S. 342, 351–53 (1914) (upholding regulation of intrastate rail rates).
101 Perez v. United States, 402 U.S. 146, 150 (1971).
102 Lopez, 514 U.S. at 559.
Congressional Research Service

9

Federalism-Based Limitations on Congressional Power: An Overview

“most frequently disputed” of the three Lopez categories,103 authorizes Congress to “regulate
purely local activities that are part of an economic ‘class of activities’ that have a substantial
effect on interstate commerce.”104 In this vein, the Court has stressed that the underlying test for
whether Congress has authority to regulate intrastate economic activity is a “modest” one,
wherein a “rational basis” needs to exist for Congress’s conclusion that the activities in question,
taken in the aggregate, would substantially affect interstate commerce.105 To determine whether
an activity has a “substantial effect” on interstate commerce, courts generally consider four non-
dispositive factors:
1. whether the activity itself “has anything to do with commerce or any sort of
economic enterprise, however broadly one might define those terms”;
2. “whether the statute in question contains an express jurisdictional element”;
3. “whether there are express congressional findings or legislative history regarding
the effects upon interstate commerce of the regulated activity”; and
4. “whether the relationship between the regulated activity and interstate commerce
is too attenuated to be regarded as substantial.”106
The Supreme Court, applying these factors, has ruled that Congress may not invoke the
Commerce Clause to regulate certain purely intrastate noneconomic activities. In United States v.
Lopez
, for instance, the Court invalidated a law prohibiting the possession of a gun near a school
zone because the law (1) regulated purely noneconomic activity; (2) lacked any jurisdictional
element related to interstate commerce; (3) was unsupported by any congressional findings
concerning interstate commercial activity; and (4) could only be viewed as regulating activity
affecting commerce if the Court were to “pile inference upon inference.”107 Similarly, in United
States v. Morrison
, the Court struck down legislation creating a federal civil remedy for the
victims of gender-motivated violence despite the existence of “numerous” congressional findings
concluding that gender-motivated crimes had an effect on interstate commerce.108 Describing the
lack of a jurisdictional element in the law at issue,109 the Court held in Morrison that Congress
may not “regulate noneconomic, violent criminal conduct based solely on that conduct’s
aggregate effect on interstate commerce.”110
By contrast, the Supreme Court has generally upheld legislation regulating economic activity
(even if intrastate) that substantially affects interstate commerce.111 For instance, in Lopez the
Court referenced the following examples of economic activities that it had held Congress could
regulate based on their substantial effects on interstate commerce: “intrastate coal mining,”112
“intrastate extortionate credit transactions,”113 “restaurants utilizing substantial interstate

103 See Patton, 451 F.3d at 622.
104 Gonzales v. Raich, 545 U.S. 1, 17 (2005).
105 See id. at 22.
106 Rancho Viejo, LLC v. Norton, 323 F.3d 1062, 1068–69 (D.C. Cir. 2003) (internal quotation marks omitted).
107 See Lopez, 514 U.S. at 561–67.
108 529 U.S. 598, 614 (2000) (“[T]he existence of congressional findings is not sufficient, by itself, to sustain the
constitutionality of Commerce Clause legislation.”).
109 Id. at 613.
110 Id. at 617.
111 See Lopez, 514 U.S. at 560.
112 Id. at 559 (citing Hodel v. Va. Surface Min. & Reclamation Ass’n, Inc., 452 U.S. 264 (1981)).
113 Id. (citing Perez v. United States, 402 U.S. 146 (1971)).
Congressional Research Service

10

Federalism-Based Limitations on Congressional Power: An Overview

supplies,”114 “inns and hotels catering to interstate guests,”115 and “production and consumption
of homegrown wheat.”116 More recently, in Gonzales v. Raich, the Court upheld the application of
the federal Controlled Substances Act (P.L. 91-513) to the cultivation and possession of marijuana
for personal, entirely intrastate medical use, on the grounds that the “failure to regulate that class
of activity would undercut the regulation of the interstate market” in marijuana.117
Regulating Inactivity
In National Federation of Independent Business (NFIB) v. Sebelius, which concerned the Patient
Protection and Affordable Care Act (ACA; P.L. 111-148), a majority of the Court agreed that the
Commerce Clause does not authorize Congress to regulate inactivity.118 Among other issues,
NFIB concerned whether the Commerce Clause authorized Congress to require “most Americans
to maintain ‘minimum essential’ health insurance coverage.”119 Writing for himself, Chief Justice
Roberts interpreted this “individual mandate” provision of the ACA to require “individuals [who
are] not engaged in commerce to purchase an unwanted product.”120 Noting that the Court’s
Commerce Clause jurisprudence presupposed that the commerce power only reached activity,121
the Chief Justice concluded that the Commerce Clause did not empower Congress “to regulate
individuals precisely because they are doing nothing,” warning that such an interpretation “would
open a new and potentially vast domain to congressional authority.”122 In so concluding, Chief
Justice Roberts rejected the government’s argument that there is “no temporal limitation in the
Commerce Clause” and that Congress may therefore regulate individuals who would one day
enter the market.123 While the Chief Justice, joined by four other members of the Court, upheld
the individual mandate under Congress’s power to “lay and collect taxes,”124 the four dissenters in
NFIB largely echoed Chief Justice Roberts’s view of the Commerce Clause.125

114 Id. (citing Katzenbach v. McClung, 379 U.S. 294 (1964)).
115 Id. (citing Heart of Atlanta Motel, Inc. v. United States, 379 U.S. 241 (1964)).
116 Id. at 559–60 (citing Wickard v. Filburn, 317 U.S. 111 (1942)).
117 Gonzales v. Raich, 545 U.S. 1, 18 (2005).
118 See 567 U.S. 519, 558 (2012) (opinion of Roberts, C.J.) (“The individual mandate forces individuals into commerce
precisely because they elected to refrain from commercial activity. Such a law cannot be sustained under a clause
authorizing Congress to ‘regulate Commerce.’”); see also id. at 649 (Scalia, Kennedy, Thomas, and Alito, JJ.,
dissenting) (“[O]ne does not regulate commerce that does not exist by compelling its existence.”).
119 See id. at 539 (majority opinion).
120 Id. at 549 (opinion of Roberts, C.J.). Chief Justice Roberts rejected the argument that there is no distinction between
activity and inactivity for purposes of the Commerce Clause, as the commerce power concerns the power to regulate
classes of activities, not “classes of individuals, apart from any activity in which they are engaged.” Id. at 555–56.
121 Id. at 551 (citing Lopez, 514 U.S. at 560; Perez v. United States, 402 U.S. 146, 154 (1971); Wickard v. Filburn, 317
U.S. 111, 125 (1942); NLRB v. Jones & Laughlin Steel Corp., 301 U.S. 1, 37 (1937)).
122 Id. at 552.
123 Id. at 557 (“The proposition that Congress may dictate the conduct of an individual today because of prophesied
future activity finds no support in our precedent. We have said that Congress can anticipate the effects on commerce of
an economic activity. But we have never permitted Congress to anticipate that activity itself in order to regulate
individuals not currently engaged in commerce.”) (citations omitted).
124 See id. at 574 (majority opinion) (“The Affordable Care Act’s requirement that certain individuals pay a financial
penalty for not obtaining health insurance may reasonably be characterized as a tax. Because the Constitution permits
such a tax, it is not our role to forbid it, or to pass upon its wisdom or fairness.”).
125 See id. at 652–53 (Scalia, Kennedy, Thomas, and Alito, JJ., dissenting) (“If Congress can reach out and command
even those furthest removed from an interstate market to participate in the market, then the Commerce Clause becomes
a font of unlimited power.... ”).
Congressional Research Service

11

Federalism-Based Limitations on Congressional Power: An Overview

Because no single opinion in NFIB enjoyed a majority of five Justices, it is uncertain whether the
Chief Justice’s and the dissenters’ conclusions regarding the Commerce Clause constitute binding
precedent.126 In practice, lower courts following NFIB have rarely invalidated Commerce Clause
legislation on “inactivity” grounds because much of what Congress regulates can be described as
a form of “activity.”127 For instance, in rejecting a challenge to another provision of the ACA—
namely, the “employer mandate,” which requires certain employers to offer a minimum level of
health insurance coverage to their employees and the employees’ dependents—the Fourth Circuit
distinguished the employer mandate from the individual mandate.128 Specifically, the appellate
court concluded that, unlike the individual mandate, the employer mandate does not “create
commerce in order to regulate it” because employers, “by their very nature,” are already
“engaged in economic activity.”129 The Fourth Circuit thus held that the employer mandate does
not compel employers to “become active in commerce,” but rather “merely regulate[s] existing
commercial activity.”130
Outside the context of the ACA, Commerce Clause challenges predicated on NFIB’s inactivity
principle have likewise been largely unsuccessful. For instance, in United States v. Roszkowski,
the First Circuit rejected the argument that 18 U.S.C. § 922(g), a law that forbids convicted felons
from possessing a firearm “in or affecting commerce,” exceeded Congress’s commerce powers
under the inactivity rationale discussed in NFIB.131 Specifically, the First Circuit concluded that
Section 922(g) was in “stark contrast to the individual mandate” at issue in NFIB, in that the
former statute did not compel individuals to become active in commerce, but instead prohibited
“affirmative conduct that has an undeniable connection to interstate commerce.”132 In another
context, the Second Circuit, in United States v. Robbins, held that the Sex Offender Registration
and Notification Act (SORNA; P.L. 109-248, tit. I) did not impermissibly regulate noneconomic
inactivity by making it a crime for a sex offender to travel in interstate commerce and knowingly
fail to update his offender registration.133 The Robbins court reasoned that, unlike those subject to
the individual mandate under the ACA, “sex offenders who are subjected to SORNA’s
requirements have all, in a sense, ‘opted in’ to the regulated group through their prior criminal
activity.”134

126 See, e.g., United States v. Robbins, 729 F.3d 131, 135 (2d Cir. 2013) (“It is not clear whether anything said about
the Commerce Clause in NFIB’s primary opinion—that of Chief Justice Roberts—is more than dicta, since Part III-A
of the Chief Justice’s opinion was not joined by any other Justice and, at least arguably, discussed a bypassed
alternative, rather than a necessary step, in the Court’s decision to uphold the Act.”); United States v. Henry, 688 F.3d
637, 641 n.5 (9th Cir. 2012) (“There has been considerable debate about whether the statements about the Commerce
Clause [in NFIB] are dicta or binding precedent.”).
127 See, e.g., United States v. McLean, 702 F. App’x 81, 87–88 (3d Cir. 2017) (“NFIB concerned Congress’ authority to
compel commercial activity, not its ability to proscribe attempted or planned criminal activity.”); Mason v. Warden,
Fort Dix FCI, 611 F. App’x 50, 53 (3d Cir. 2015) (“Contrary to Mason’s contention, that Commerce Clause ruling does
not undermine his Hobbs Act convictions, for neither the Hobbs Act itself, nor the facts of his case, involve compelling
commerce.”).
128 Liberty Univ., Inc. v. Lew, 733 F.3d 72, 93 (4th Cir. 2013).
129 Id.
130 Id. (quoting NFIB v. Sebelius, 567 U.S. 519, 552 (2012) (opinion of Roberts, C.J.)).
131 700 F.3d 50, 58 (1st Cir. 2012).
132 Id. For other unsuccessful challenges to 18 U.S.C. § 922(g) based on NFIB, see United States v. Bron, 709 F. App’x
551, 554 (11th Cir. 2017); United States v. Alcantar, 733 F.3d 143, 146 (5th Cir. 2013).
133 See 729 F.3d 131, 135–36 (2d Cir. 2013).
134 Id. at 136. In addition, the Second Circuit noted that “the registration requirement that Robbins himself failed to
meet was triggered by activity: his change of residence and travel across state lines.” Id. For other unsuccessful
challenges to SORNA based on NFIB, see, e.g., United States v. White, 782 F.3d 1118, 1125 (10th Cir. 2015); United
Congressional Research Service

12

Federalism-Based Limitations on Congressional Power: An Overview

Although lower courts generally have not relied on NFIB to invalidate federal actions as outside
the Commerce Clause, the Fifth Circuit’s ruling in BST Holdings, LLC v. Occupational Safety &
Health Administration
is an exception.135 In BST, the court stayed enforcement of an
Occupational Safety and Health Administration (OSHA) mandate that had required employees of
covered employers to undergo COVID-19 vaccination or else take weekly COVID tests and wear
masks.136 Among other reasons for staying the mandate, the court determined that it “likely
exceed[ed] the federal government’s authority under the Commerce Clause because it regulates
noneconomic inactivity that falls squarely within the States’ police power.”137 Citing NFIB, the
Fifth Circuit stated that “[a] person’s choice to remain unvaccinated and forgo regular testing is
noneconomic inactivity.”138 Following the Fifth Circuit’s ruling, however, legal challenges to the
OSHA mandate were consolidated in the Sixth Circuit, which disagreed with the Fifth Circuit’s
reasoning and dissolved the stay.139 Rejecting the Fifth Circuit’s Commerce Clause analysis, the
Sixth Circuit concluded that OSHA’s vaccination mandate “regulates economic activity by
regulating employers.”140 The Supreme Court eventually reinstated the stay on the basis that
Congress had not statutorily authorized OSHA to impose the mandate.141 The Court’s opinion did
not address the mandate’s validity under the Commerce Clause.
Treaty Power
At least since the Supreme Court’s 1920 ruling in Missouri v. Holland,142 courts have recognized
that Congress has considerable power, even beyond the scope of its Article I enumerated powers,
when legislating to implement a treaty ratified pursuant to Article II, Section 2 of the
Constitution. In Holland, the Supreme Court upheld a federal law regulating the killing of
migratory birds that had been adopted pursuant to a treaty between the United States and Great
Britain, even though a lower court had concluded that a similar statute enacted in the absence of a
treaty was beyond the scope of Congress’s enumerated powers and therefore unconstitutional on
Tenth Amendment grounds.143 The Court explained in Holland that, to evaluate the statute’s
constitutionality, it was

States v. Howell, 557 F. App’x 579, 580 (7th Cir. 2014); United States v. Anderson, 771 F.3d 1064, 1070 (8th Cir.
2014).
Another federal statute that has been the subject of several unsuccessful Commerce Clause challenges based on NFIB’s
inactivity principle is 18 U.S.C. § 2251, which, among other things, prohibits the production of child pornography. See,
e.g.
, United States v. Humphrey, 845 F.3d 1320, 1323 (10th Cir. 2017) (upholding a federal law prohibiting the
production of child pornography because producing pornography made the defendant “akin to the farmer in Wickard,
not the uninsured individuals in NFIB”); United States v. Sullivan, 797 F.3d 623, 632 (similar); United States v. Parton,
749 F.3d 1329, 1331 (11th Cir. 2014) (similar).
135 17 F.4th 604 (5th Cir. 2021).
136 Id. at 609.
137 Id. at 617.
138 Id.
139 See In re MCP No. 165, 21 F.4th 357 (6th Cir. 2021).
140 Id. at 384.
141 See NFIB v. Dep’t of Lab., 142 S. Ct. 661, 665 (2022) (“Permitting OSHA to regulate the hazards of daily life—
simply because most Americans have jobs and face those same risks while on the clock—would significantly expand
OSHA’s regulatory authority without clear congressional authorization.”). Following the Supreme Court’s ruling,
OSHA withdrew the mandate and the Sixth Circuit dismissed as moot the petitions challenging it.
142 252 U.S. 416 (1920).
143 See id. at 432.
Congressional Research Service

13

Federalism-Based Limitations on Congressional Power: An Overview

not enough to refer to the Tenth Amendment, reserving the powers not delegated to the
United States, because by Article 2, Section 2, the power to make treaties is delegated
expressly, and by Article 6 treaties made under the authority of the United States, along
with the Constitution and laws of the United States made in pursuance thereof, are declared
the supreme law of the land.144
The Holland Court thus concluded that, as long as the treaty was valid, there could “be no dispute
about the validity of the statute ... as a necessary and proper means to execute the powers of
Government.”145 Holland therefore stands for the proposition that Congress generally has the
power to enact legislation to implement a treaty even where it would lack the power to act on the
same subject matter in the treaty’s absence.146 However, the complete extent to which Congress
may intrude upon traditional state authority through treaty-implementing legislation remains
unclear. Some scholars have suggested, for example, that there is reason to believe that Congress
could not enact legislation that infringes upon the essential character of the states, such as
legislation that commandeers state executive and legislative authorities.147
In Bond v. United States, the petitioner asked the Court to reconsider the extent to which the
Tenth Amendment constrains Congress’s ability to enact treaty-implementing legislation.148 The
petitioner in Bond had been convicted under the Chemical Weapons Convention Implementation
Act of 1998 (CWCIA; P.L. 105-277)149 for attempting to poison her husband’s paramour with
toxic chemicals.150 She argued that the act, as applied to her, impermissibly intruded upon matters
falling under traditional state authority,151 and that Congress may not act beyond the scope of its
enumerated powers to implement a treaty.152 However, the Court ultimately opted not to revisit its
earlier statement in Missouri v. Holland regarding the scope of the Treaty Power or provide any
clear signal as to whether it agreed with the earlier Court’s characterization.153 Although three
concurring Justices argued that the scope of Congress’s power to implement a treaty does not
extend beyond its enumerated authority,154 the majority opinion of the Court declined to reach the

144 Id.
145 Id.
146 Since Holland, reviewing courts have deemed a number of federal statutes implementing treaty requirements
constitutionally permissible under the Necessary and Proper Clause. See, e.g., United States v. Rife, 33 F.4th 838, 841
(6th Cir. 2022) (upholding statute that prohibits engaging in “illicit sexual conduct” in foreign places, 18 U.S.C.
§ 2423(c), as necessary and proper to implement the Optional Protocol to the United Nations Convention on the Rights
of the Child on the Sale of Children, Child Prostitution and Child Pornography), cert. denied, No. 22-5306, 2022 WL
9551050 (U.S. Oct. 17, 2022); United States v. Ferreira, 275 F.3d 1020, 1027–28 (11th Cir. 2001) (upholding Hostage
Taking Act, 18 U.S.C. § 1203, as necessary and proper to implement the International Convention Against the Taking
of Hostages); United States v. Wang Kun Lue, 134 F.3d 79, 84 (2d Cir. 1997) (same). See also United States v. Lara,
541 U.S. 193, 201 (2004) (citing to the Indian Commerce Clause and Treaty Clause as providing Congress with power
to legislate on Indian tribe issues, and stating that “treaties ... can authorize Congress to deal with matters with which
otherwise Congress could not deal”) (internal quotations omitted).
147 See generally Edward T. Swaine, Does Federalism Constrain the Treaty Power?, 103 COLUM. L. REV. 403 (2003).
For criticism of the Supreme Court’s decision in Missouri v. Holland, and arguments that the Treaty Power may not
expand Congress’s legislative power, see Nicholas Quinn Rosenkranz, Executing the Treaty Power, 118 HARV. L. REV.
1867, 1868 (2005).
148 572 U.S. 844, 853 (2014).
149 18 U.S.C. § 229.
150 572 U.S. at 848.
151 Id. at 855.
152 Id.
153 Id.
154 See id. at 867–82 (Scalia, J., concurring in the judgment).
Congressional Research Service

14

Federalism-Based Limitations on Congressional Power: An Overview

constitutional issue.155 The Court instead determined that the criminal provisions of the CWCIA
should “be read consistent with principles of federalism inherent in our constitutional structure,”
and therefore should not be interpreted to cover the petitioner’s conduct.156 Holland therefore
remains good law.157 However, Bond makes clear that, irrespective of related treaties, statutes
must be interpreted consistent with the background assumption that “Congress normally
preserves the constitutional balance between the National Government and the States.”158
Congress’s Powers Under the Civil War Amendments
The Thirteenth, Fourteenth, and Fifteenth Amendments to the Constitution—referred to
collectively as the “Civil War Amendments” or “Reconstruction Amendments”159—grant
Congress additional powers beyond those set forth in the original Constitution. The United States
ratified each of these amendments after the Civil War to end slavery and secure equal rights for
formerly enslaved persons.160 The Thirteenth Amendment prohibits slavery and involuntary
servitude within the United States.161 The Fourteenth Amendment, among other things, provides
that no state shall “deprive any person of life, liberty, or property, without due process of law” or
“deny to any person within its jurisdiction the equal protection of the laws.”162 The Fifteenth
Amendment guarantees that the right to vote “shall not be denied or abridged by the United States
or by any State on account of race, color, or previous condition of servitude.”163 The Civil War
Amendments significantly altered the balance of power between the states and the federal
government164 by limiting state authority and granting Congress new powers to “secure to all

155 Id. at 855 (majority opinion).
156 Id. at 856. For further discussion of the Bond ruling, see CRS Report R42968, Bond v. United States: Validity and
Construction of the Federal Chemical Weapons Statute
, by Charles Doyle.
157 In the aftermath of Bond, the Ninth Circuit rejected a constitutional challenge to the CWCIA, finding that the
statute, when applied to a crime that was not “purely local” in nature, was “within the constitutional powers of the
federal government under the Necessary and Proper Clause and the Treaty Power.” United States v. Fries, 781 F.3d
1137, 1148 (9th Cir. 2015) (quoting United States v. Bond, 681 F.3d 149, 165 (3d Cir. 2012), rev’d,, 572 U.S. 844
(2014)). See also United States v. Mikhel, 889 F.3d 1003, 1023–24 (9th Cir. 2018) (upholding Hostage Taking Act
under the Treaty Power and noting that, “[a]lthough this broad reading of the Necessary and Proper Clause has been
criticized and debated ... the Supreme Court has never undertaken to clarify or correct our understanding. We are thus
bound by our prior cases.” (citation omitted)).
158 Bond, 572 U.S. at 862 (internal quotations omitted) (quoting Bond I, 564 U,S, 211, 222 (2011)).
159 This shorthand reflects the fact that the three amendments were ratified between 1865 and 1870 in the wake of the
Union’s victory in the American Civil War. See, e.g., Fitzpatrick v. Bitzer, 427 U.S. 445, 455 (1976) (using the term
“Civil War Amendments”); Oregon v. Mitchell, 400 U.S. 112, 126 (1970) (same); Nw. Austin Mun. Util. Dist. No. One
v. Holder, 557 U.S. 193, 223 (2009) (Thomas, J., concurring in part and dissenting in part) (using the term
“Reconstruction Amendments”). It should be noted, however, that these three amendments were neither drafted nor
enacted as a package. See generally John E. Nowak, Federalism and the Civil War Amendments, 23 OHIO N.U. L. REV.
1209, 1211–15 (1997) (overviewing history of the passage and ratification of the Civil War Amendments).
160 See Ex parte Virginia, 100 U.S. 339, 344–45 (1879) (“One great purpose of these amendments was to raise the
colored race from that condition of inferiority and servitude in which most of them had previously stood, into perfect
equality of civil rights with all other persons within the jurisdiction of the States.”).
161 U.S. CONST. amend. XIII, § 1 (“Neither slavery nor involuntary servitude, except as a punishment for crime whereof
the party shall have been duly convicted, shall exist within the United States, or any place subject to their
jurisdiction.”).
162 Id. amend. XIV, § 1.
163 Id. amend. XV, § 1.
164 See Seminole Tribe of Fla. v. Florida, 517 U.S. 44, 59 (1996) (“[T]he Fourteenth Amendment, by expanding federal
power at the expense of state autonomy ... fundamentally altered the balance of state and federal power struck by the
Constitution.”); City of Richmond v. J.A. Croson Co., 488 U.S. 469, 490 (1989) (“The Civil War Amendments
Congressional Research Service

15

Federalism-Based Limitations on Congressional Power: An Overview

persons the enjoyment of perfect equality of civil rights and the equal protection of the laws
against State denial or invasion.”165
Each of the Civil War Amendments gives Congress the “power to enforce” its provisions “by
appropriate legislation.”166 Congress’s power to enforce the Civil War Amendments goes beyond
legislation that simply prohibits unconstitutional conduct. Rather, Congress may legislate
prophylactically to deter or remedy constitutional violations “even if in the process it prohibits
conduct which is not itself unconstitutional.”167 For example, to enforce the Thirteenth
Amendment’s prohibition on slavery, Congress possesses constitutional authority to eliminate the
“badges and the incidents of slavery,” such as by banning racial discrimination in the sale of real
property.168 Similarly, to enforce the Fifteenth Amendment’s prohibition on racially
discriminatory voting restrictions, Congress may ban the use of literacy tests in state and national
elections,169 even though literacy tests are not themselves always unconstitutional.170
Likely because of its broad, general guarantees of “due process” and “equal protection of the
laws,”171 issues concerning Congress’s power under the Fourteenth Amendment arise more often
than the other two Civil War Amendments. The remainder of this section thus focuses on
Congress’s enforcement power under Section 5 of the Fourteenth Amendment.172

themselves worked a dramatic change in the balance between congressional and state power over matters of race.”);
Akhil Reed Amar, The Bill of Rights as a Constitution, 100 YALE L.J. 1131, 1195 (1991) (“[The Civil War
Amendments] radically transform[ed] the nature of American federalism.”). One such fundamental change is that, prior
to the Civil War Amendments, the Supreme Court had held that the protections in the Bill of Rights did not apply to the
actions of the states. See, e.g., Barron ex rel. Tiernan v. Mayor of Baltimore, 32 U.S. 243, 247 (1833) (holding that the
Fifth Amendment does not apply to the states). Following the enactment of the Fourteenth Amendment, however, the
Court has held that many of the protections of the Bill of Rights are applicable to the states. See McDonald v. City of
Chicago, 561 U.S. 742, 765 n.13, (2010) (noting the few provisions of the Bill of Rights that the Court has not held to
be incorporated against the states).
165 Ex parte Virginia, 100 U.S. 339, 346 (1879). See also id. at 345 (“[The Civil War Amendments] were intended to
be, what they really are, limitations of the power of the States and enlargements of the power of Congress.”).
166 U.S. CONST. amend. XIII, § 2; id. amend. XIV, § 5; id. amend. XV, § 2.
167 City of Boerne v. Flores, 521 U.S. 507, 518 (1997), superseded by statute in part, Religious Land Use and
Institutionalized Persons Act of 2000 (RLUIPA), P.L. 106-274, 114 Stat. 803 (codified at 42 U.S.C. § 2000cc).
168 See Jones v. Alfred H. Mayer Co., 392 U.S. 409, 413, 440–43 (1968) (holding that statute banning “racial
discrimination, private as well as public, in the sale or rental of property” was “a valid exercise of the power of
Congress to enforce the Thirteenth Amendment”); The Civil Rights Cases, 109 U.S. 3, 21 (1883) (“[Under the
Thirteenth Amendment,] Congress has a right to enact all necessary and proper laws for the obliteration and prevention
of slavery, with all its badges and incidents.... ”).
169 See Oregon v. Mitchell, 400 U.S. 112, 118 (1970) (opinion of Black, J.) (“Congress, in the exercise of its power to
enforce the Fourteenth and Fifteenth Amendments, can prohibit the use of literacy tests or other devices used to
discriminate against voters on account of their race in both state and federal elections.”); accord Katzenbach v.
Morgan, 384 U.S. 641, 649 (1966).
170 See Lassiter v. Northampton Cnty. Bd. of Elections, 360 U.S. 45, 50–53 (1959) (holding that use of literacy test for
voters, if “fair on its face” and “neutral[ly]” applied, is constitutional).
171 U.S. CONST. amend. XIV, § 1.
172 Congress’s independent powers to enforce the other two Civil War Amendments are substantial, however. For
example, the Thirteenth Amendment has been relied on to uphold federal hate crimes legislation, see, e.g., United
States v. Diggins, 36 F.4th 302, 309 (1st Cir. 2022) (collecting federal cases upholding the Shepard-Byrd Hate Crimes
Prevention Act under Section 2 of the Thirteenth Amendment), while the Fifteenth Amendment has been relied on to
support voting rights legislation, see, e.g., South Carolina v. Katzenbach, 383 U.S. 301, 337 (1966) (upholding the
Voting Rights Act of 1965 under Section 2 of the Fifteenth Amendment).
Congressional Research Service

16

Federalism-Based Limitations on Congressional Power: An Overview

Although Congress’s power to enforce the Fourteenth Amendment is broad, “it is not
unlimited.”173 In particular, the Supreme Court has recognized two major limitations to
Congress’s power under Section 5 of the Fourteenth Amendment. First, Congress may legislate
only against “state action”: it may not rely on the Fourteenth Amendment to regulate the conduct
of private (i.e., non-state) actors.174 Second, Congress may legislate only remedially under the
Fourteenth Amendment; it may not change the substantive scope of the rights guaranteed.175 In
other words, enforcement legislation must be “targeted at ‘conduct transgressing the Fourteenth
Amendment’s substantive provisions,’”176 such that there is “a congruence and proportionality
between the injury to be prevented or remedied and the means adopted to that end.”177
The State Action Requirement
The first limitation—the “state action requirement”—derives from the text of Section 1 of the
Fourteenth Amendment, which explicitly proscribes only certain actions undertaken by
“State[s].”178 The Supreme Court has interpreted this language to mean that Congress may
legislate only to combat discrimination by or through state governments; it may not rely on the
Fourteenth Amendment to regulate “merely private conduct, however discriminatory or
wrongful.”179 The state action requirement thus “preserves an area of individual freedom by
limiting the reach of federal law and federal judicial power.”180 It also avoids imposing liability
on state agencies and officials “for conduct for which they cannot fairly be blamed.”181
For example, in the 1883 Civil Rights Cases, the Supreme Court held that Congress had no
authority under the Fourteenth Amendment to prohibit racial discrimination in places of public
accommodation (such as inns, theaters, and railroads) because such laws targeted discrimination

173 City of Boerne v. Flores, 521 U.S. 507, 518, superseded by statute in part, Religious Land Use and Institutionalized
Persons Act of 2000 (RLUIPA), P.L. 106-274, 114 Stat. 803 (codified at 42 U.S.C. § 2000cc) (quoting Mitchell, 400
U.S. at 128 (opinion of Black, J.)).
174 See United States v. Morrison, 529 U.S. 598, 620–21 (2000) (“The language and purpose of the Fourteenth
Amendment place certain limitations on the manner in which Congress may attack discriminatory conduct.... Foremost
among these limitations is the time-honored principle that the Fourteenth Amendment, by its very terms, prohibits only
state action.”). The Fifteenth Amendment, too, is generally understood to require state action. See, e.g., Smith v.
Allwright, 321 U.S. 649, 664 (1944) (holding that racial discrimination by political party in primary elections
constitutes “state action within the meaning of the Fifteenth Amendment”). But see Note, The Strange Career of ‘State
Action’ Under the Fifteenth Amendment
, 74 YALE L.J. 1448, 1449 (1965) (noting that early Supreme Court cases
“construe[d] congressional enforcement power under the fifteenth amendment to reach private individuals”). Notably,
the Thirteenth Amendment lacks any state action requirement. See Griffin v. Breckenridge, 403 U.S. 88, 105 (1971)
(upholding, under the Thirteen Amendment, a federal cause of action for victims of racially discriminatory conspiracies
committed by private citizens).
175 See City of Boerne, 521 U.S. at 519 (“The design of the [Fourteenth] Amendment and the text of § 5 are inconsistent
with the suggestion that Congress has the power to decree the substance of the Fourteenth Amendment’s restrictions on
the States.”). In addition, when legislating under the Fourteenth and Fifteenth Amendments, Congress may not violate
“the fundamental principle of equal sovereignty” by treating states unequally without sufficient reason. See Shelby
Cnty. v. Holder, 570 U.S. 529, 542 (2013). This equal sovereignty limit is explained in more detail in a separate section
of this report. See infra “Equal Sovereignty Doctrine.”
176 Coleman v. Ct. of Appeals of Md., 566 U.S. 30, 36 (2012) (plurality opinion) (quoting Fla. Prepaid Postsecondary
Educ. Expense Bd. v. Coll. Sav. Bank, 527 U.S. 627, 639 (1999)).
177 City of Boerne, 521 U.S. at 520.
178 See U.S. CONST. amend. XIV, § 1 (“No State shall make or enforce any law which shall abridge.... ”) (emphasis
added).
179 Shelley v. Kraemer, 334 U.S. 1, 13 (1948).
180 Lugar v. Edmondson Oil Co., 457 U.S. 922, 936 (1982).
181 Id.
Congressional Research Service

17

Federalism-Based Limitations on Congressional Power: An Overview

by private citizens.182 Much more recently, the Supreme Court reaffirmed the state action
requirement in United States v. Morrison, holding that Congress could not create a federal remedy
for victims of gender-motivated violence under Section 5 because the law “is directed not at any
State or state actor, but at individuals who have committed criminal acts motivated by gender
bias.”183
Conduct by ostensibly private actors will be treated as a state action only if “there is such a ‘close
nexus between the State and the challenged action’ that seemingly private behavior ‘may be fairly
treated as that of the State itself.’”184 Such a close nexus requires that (1) “the claimed
constitutional deprivation ... resulted from the exercise of a right or privilege having its source in
state authority”185 and (2) “the party charged with the deprivation must be a person who may
fairly be said to be a state actor.”186 For example, if a private citizen is a “willful participant in
joint activity with the State or its agents” he or she may be held to account under the Fourteenth
Amendment as if he or she were a state official.187 Whether an individual may fairly be said to be
a state actor is a “necessarily fact-bound inquiry.”188 Even so, discriminatory state legislation or
conduct by individual state officials acting in their official capacity will satisfy the state action
requirement.189
“Congruence and Proportionality” for Remedial Legislation
The second major limitation on Congress’s Fourteenth Amendment power is that enforcement
legislation must be “remedial” in nature.190 Congress is not limited to legislating against actual
constitutional violations; it may go further “to remedy and to deter violation of [constitutional
rights] by prohibiting a somewhat broader swath of conduct, including that which is not itself
forbidden” by the Fourteenth Amendment.191 Nonetheless, Congress can only enforce the rights
guaranteed by the Amendment; it may not alter the substantive scope of the rights themselves.192

182 See 109 U.S. 3, 11 (“Individual invasion of individual rights is not the subject-matter of the amendment.”); id. at 13
(“[U]ntil some State law has been passed, or some State action through its officers or agents has been taken, adverse to
the rights of citizens sought to be protected by the Fourteenth Amendment, no legislation of the United States under
said amendment, nor any proceeding under such legislation, can be called into activity.... ”). As a result of the state
action limit on its Fourteenth Amendment powers, Congress has instead relied on its Commerce Clause powers to
prohibit discrimination in public accommodations. See, e.g., Heart of Atlanta Motel, Inc. v. United States, 379 U.S.
241, 261 (1964) (holding that Congress has authority to prohibit racial discrimination in hotels under the Commerce
Clause); Katzenbach v. McClung, 379 U.S. 294, 304 (1964) (holding that Congress has power to prohibit racial
discrimination in restaurants under the Commerce Clause). See generally supra “Commerce Clause.”
183 529 U.S. 598, 626 (2000).
184 Brentwood Acad. v. Tenn. Secondary Sch. Athletic Ass’n, 531 U.S. 288, 295 (2001) (quoting Jackson v. Metro.
Edison Co., 419 U.S. 345, 351 (1974)).
185 Lugar, 457 U.S. at 938–89.
186 Id. at 937.
187 United States v. Price, 383 U.S. 787, 794 (1966).
188 Lugar, 457 U.S. at 939.
189 See, e.g., Ex parte Virginia, 100 U.S. 339, 346 (1879) (“Congress is empowered to enforce [the Fourteenth
Amendment], and to enforce against State action, however put forth, whether that action be executive, legislative, or
judicial.”); United States v. Raines, 362 U.S. 17, 25 (1960) (“[D]iscrimination by state officials, within the course of
their official duties ... is certainly, a[] ‘state action’ and the clearest form of it . . . .”).
190 See Tennessee v. Lane, 541 U.S. 509, 520 (2004) (distinguishing between “appropriate remedial” legislation
enforcing the Fourteenth Amendment and unconstitutional “substantive redefinition” of the Amendment).
191 Kimel v. Fla. Bd. of Regents, 528 U.S. 62, 81 (2000).
192 City of Boerne v. Flores, 521 U.S. 507, 519 (1997), superseded by statute in part, Religious Land Use and
Congressional Research Service

18

link to page 34 Federalism-Based Limitations on Congressional Power: An Overview

In the landmark case City of Boerne v. Flores, the Supreme Court crafted a test to determine when
legislation to enforce the Fourteenth Amendment sweeps so broadly as to be unconstitutional.
Boerne addressed the constitutionality of the Religious Freedom Restoration Act (RFRA; P.L.
103-141) as it applied to the states.193 RFRA prohibited governments from substantially
burdening any person’s exercise of religion unless it was “in furtherance of a compelling
governmental interest” and used “the least restrictive means” of furthering that interest.194
Congress enacted RFRA in response to an earlier Supreme Court decision, Employment Division
v. Smith
, which held that neutral, generally applicable state laws were not subject to heightened
scrutiny under the First Amendment, even when such laws were applied to religiously motivated
practices.195 Thus, in Smith, Oregon could enforce its general criminal prohibition on peyote use
against the sacramental use of that drug in Native American churches without violating the First
Amendment.196 Through RFRA, Congress sought to invoke its Fourteenth Amendment powers to
establish a stricter test for religious liberty claims than the Smith standard. Boerne held, however,
that RFRA exceeded Congress’s power because Congress could not “decree the substance of the
Fourteenth Amendment’s restrictions on the States.”197 Although Congress can act to “remedy or
prevent unconstitutional actions,” the Supreme Court explained that “a congruence and
proportionality between the injury to be prevented or remedied and the means adopted to that
end” must exist.198 The Court found that RFRA failed the proportionality requirement because the
legislative record lacked “examples of modern instances of generally applicable laws passed
because of religious bigotry,” and the statute’s sweeping coverage threatened general state laws
“of almost every description and regardless of subject matter.”199
Courts applying Boerne’s “congruence and proportionality” test typically use a three-step
approach. First, the court “identif[ies] with some precision the scope of the constitutional right”
that the legislation is intended to remedy.200 Second, the court examines “whether Congress
identified a history and pattern of unconstitutional [violations] by the States” as to the
constitutional right at issue.201 Finally, the court compares the scope of the law to the history of
violations to determine whether the legislation is “so out of proportion to a supposed remedial or
preventive object that it cannot be understood as responsive to, or designed to prevent,
unconstitutional behavior.”202
Nearly all of the Supreme Court decisions applying Boerne arise in the context of congressional
attempts to abrogate state immunity to suit under the Eleventh Amendment. As explained in detail
below,203 states generally cannot be sued unless Congress validly revokes their Eleventh

Institutionalized Persons Act of 2000 (RLUIPA), P.L. 106-274, 114 Stat. 803 (codified at 42 U.S.C. § 2000cc)
(“[Congress] has been given the power “to enforce” [the Fourteenth Amendment,] not the power to determine what
constitutes a constitutional violation.”).
193 Id. at 511.
194 Id. at 515 –16 (quoting 42 U.S.C. § 2000bb-1).
195 494 U.S. 872, 880–85 (1990).
196 Id. at 874, 890.
197 City of Boerne, 521 U.S. at 519.
198 Id. at 519–20.
199 Id. at 530–34.
200 Bd. of Trs. of Univ. of Ala. v. Garrett, 531 U.S. 356, 365 (2001).
201 Id. at 368. See also Coleman v. Ct. of Appeals of Md., 566 U.S. 30, 37 (2012) (plurality opinion) (holding that
remedial legislation requires “evidence of a pattern of state constitutional violations”).
202 Kimel v. Fla. Bd. of Regents, 528 U.S. 62, 86 (2000) (quoting City of Boerne, 521 U.S. at 532).
203 See “The Eleventh Amendment and State Sovereign Immunity.”
Congressional Research Service

19

Federalism-Based Limitations on Congressional Power: An Overview

Amendment immunity.204 Congress also cannot generally use its Article I powers, such as its
Commerce Clause power, to abrogate the states’ Eleventh Amendment immunity,205 save in
narrow situations in which states implicitly consented to suit as part of the “plan of the
[Constitutional] convention”206 or when the congressional power at issue is “complete in
itself.”207 As a result, Congress must often rely on its enforcement power under the Fourteenth
Amendment if it seeks to pass legislation that subjects states to suit in federal court.208
The decisions applying Boerne to purported abrogations of Eleventh Amendment immunity have
sharply divided the Supreme Court.209 As a result, it can be difficult to predict how the Court will
rule in any particular case,210 and the decisions can be highly fact-bound. For example, in the
context of the Americans with Disabilities Act of 1990 (ADA; P.L. 101-336), the Court has held
that Congress cannot abrogate state immunity with respect to Title I of the ADA (which prohibits
disability discrimination in employment),211 but that it can abrogate state immunity with respect
to some applications of Title II of the ADA (which prohibits disability discrimination in the
provision of public services).212 In the context of the Family Medical Leave Act (FMLA; P.L.
103-3), the Court has held that Congress may validly abrogate state immunity with respect to
FMLA’s guarantee of leave for an employee to take care of ill family members (the “family-care”
provisions),213 but not with respect to FMLA’s guarantee of leave when the employee is sick (the
“self-care” provisions).214
Generally speaking, these cases often turn on whether the legislative record establishes a history
or pattern of state violations of the constitutional right at issue.215 For example, in Tennessee v.
Lane
, the Supreme Court found that the legislative record showed a pattern of “unconstitutional
discrimination against persons with disabilities in the provision of public services” that justified
congressional abrogation of state immunity with respect to Title II of the ADA.216 In contrast, in

204 See infra “The Eleventh Amendment and State Sovereign Immunity” (explaining constitutional basis and scope of
state sovereign immunity).
205 Seminole Tribe of Fla. v. Florida, 517 U.S. 44, 72–73 (1996); Allen v. Cooper, 140 S. Ct. 994, 1002 (2020).
206 Cent. Va. Cmty. Coll. v. Katz, 546 U.S. 356, 377 (2006).
207 Torres v. Tex. Dep’t of Pub. Safety, 142 S. Ct. 2455, 2463 (2022) (quoting PennEast Pipeline Co., LLC v. New
Jersey, 141 S. Ct. 2244, 2263 (2021)).
208 See, e.g., Fitzpatrick v. Bitzer, 427 U.S. 445, 456 (1976) (permitting congressional abrogation of state sovereign
immunity pursuant to Section 5 of the Fourteenth Amendment). See also infra “The Eleventh Amendment and State
Sovereign Immunity.”
209 See, e.g., Coleman v. Ct. of Appeals of Md., 566 U.S. 30 (2012) (holding abrogation of immunity invalid by a 5-4
decision with two separate concurrences); Tennessee v. Lane, 541 U.S. 509 (2004) (holding abrogation of immunity
valid by a 5-4 decision with two separate concurring opinions and three separate dissenting opinions); Bd. of Trs. of
Univ. of Ala. v. Garrett, 531 U.S. 356 (2001) (holding attempted abrogation of immunity invalid by a 5-4 decision).
210 See Coleman, 566 U.S. at 44 (Scalia, J., concurring) (“[T]he varying outcomes we have arrived at under the
‘congruence and proportionality’ test make no sense.”).
211 Garrett, 531 U.S. at 360–61.
212 Lane, 541 U.S. at 533–34.
213 Nev. Dep’t of Hum. Res. v. Hibbs, 538 U.S. 721, 725 (2003).
214 Coleman, 566 U.S. at 33–34.
215 Compare Garrett, 531 U.S. at 370 (finding that “Congress assembled only ... minimal evidence of unconstitutional
state discrimination in employment against the disabled”) with id. at 377–79 (Breyer, J., dissenting) (finding that
“Congress compiled a vast legislative record documenting ‘massive, society-wide discrimination’ against persons with
disabilities” including “roughly 300 examples of discrimination by state governments themselves” (quoting S. REP. NO.
101-116, at 8–9 (1989))).
216 See Lane, 541 U.S. at 525–28.
Congressional Research Service

20

Federalism-Based Limitations on Congressional Power: An Overview

Board of Trustees of the University of Alabama v. Garrett, the Court struck down legislation that
applied the ADA to state government employment decisions based (in part) on its finding that
there was no “history and pattern of unconstitutional employment discrimination by the States
against the disabled.”217
Another important consideration for Congress’s power under the Fourteenth Amendment is the
particular constitutional right at issue. Courts have tended to be more deferential to uses of
Congress’s Fourteenth Amendment power when the violations involve a suspect classification
(such as race or sex) or a fundamental right. For example, one reason that the Supreme Court
found a valid abrogation with respect to FMLA’s family-care leave provisions was that the
legislation sought to combat sex discrimination in the workplace, and courts typically subject
distinctions based on sex to heightened scrutiny.218 In contrast, the Court found a purported
abrogation invalid with respect to the ADA’s employment disability discrimination provisions in
part because disability classifications are subject only to rational-basis review.219 The Court later
limited that holding as to Title II of the ADA, however, largely because the particular variety of
disability discrimination at issue—denial of courthouse access—involved not just discrimination
but also the fundamental right of due process of law.220
Courts applying the Boerne test also evaluate the breadth of the congressional remedy in relation
to the severity of the constitutional violation that Congress seeks to prevent.221 Thus, in Tennessee
v. Lane
, the Court held that there was a valid abrogation of immunity in part because Congress
chose a “limited” remedy of affording reasonable accommodations to the disabled.222 In contrast,
Boerne itself found that RFRA lacked congruence and proportionality because the act would
subject states to “the most demanding test known to constitutional law” even when the conduct at
issue did not violate the Constitution.223
A court need only assess whether a challenged statute satisfies the congruence and proportionality
test if the legislation is “prophylactic”; that is, if it purports to regulate conduct beyond actual
violations of the Fourteenth Amendment.224 When Congress merely creates a cause of action for
activity that “actually violates the Fourteenth Amendment,” Congress may abrogate state
sovereign immunity without a showing of congruence and proportionality.225
As a practical matter, there are two main steps that legislators may consider to decrease the
likelihood that a court will conclude that a given law exceeds Congress’s Fourteenth Amendment
enforcement powers. First, Congress may develop a substantial legislative record that

217 Garrett, 531 U.S. at 368.
218 Hibbs, 538 U.S. at 728.
219 See Garrett, 531 U.S. at 366–67.
220 See Lane, 541 U.S. at 522–23.
221 See City of Boerne v. Flores, 521 U.S. 507, 530 (1997), superseded by statute in part, Religious Land Use and
Institutionalized Persons Act of 2000 (RLUIPA), P.L. 106-274, 114 Stat. 803 (codified at 42 U.S.C. § 2000cc).
(“Strong measures appropriate to address one harm may be an unwarranted response to another, lesser one.”).
222 Lane, 541 U.S. at 531–34.
223 City of Boerne, 521 U.S. at 534–35; see also id. at 532 (“Sweeping coverage ensures [RFRA’s] intrusion at every
level of government, displacing laws and prohibiting official actions of almost every description and regardless of
subject matter.”).
224 Nev. Dep’t of Hum. Res. v. Hibbs, 538 U.S. 721, 728 (2003) (defining “prophylactic legislation” as a law that
“proscribes facially constitutional conduct, in order to prevent and deter unconstitutional conduct”).
225 See United States v. Georgia, 546 U.S. 151, 159 (2006) (concluding that Congress may validly abrogate state
sovereign immunity to the extent a law merely “creates a private cause of action for damages against the States for
conduct that actually violates the Fourteenth Amendment”).
Congressional Research Service

21

Federalism-Based Limitations on Congressional Power: An Overview

demonstrates a “history and pattern” of constitutional violations justifying the remedial
legislation.226 Congress will have more leeway to craft a legislative remedy when the history of
constitutional violations is severe,227 implicates a fundamental right,228 or involves a suspect
classification.229 Second, Congress may craft its remedy “in narrow terms to address or prevent”
those constitutional violations.230 Although Congress has power to regulate conduct that does not
itself violate the Fourteenth Amendment, under Boerne it may wish to avoid sweeping too
broadly in creating a remedy.231
Necessary and Proper Clause
Supplementing Congress’s enumerated powers is the Necessary and Proper Clause, which grants
Congress the power to “make all Laws which shall be necessary and proper for carrying into
Execution” the powers enumerated in Article I of the Constitution, as well as “all other Powers
vested by the Constitution in the Government of the United States, or in any Department or
Officer thereof.”232 The Necessary and Proper Clause is typically understood not as an
independent grant of congressional power,233 but as an extension of all the other powers vested in
the federal government, including Congress’s enumerated Article I powers.234 Thus, explicitly or

226 See, e.g., Lane, 541 U.S. at 530 (finding Title II of the ADA an “appropriate response” to a “history and pattern of
unequal treatment” of persons with disabilities).
227 See, e.g., South Carolina v. Katzenbach, 383 U.S. 301, 308 (1966) (approving “stringent new remedies” to “banish
the blight of racial discrimination in voting, which has infected the electoral process in parts of our country for nearly a
century”), abrogated in part by Shelby Ctny. v. Holder, 570 U.S. 529 (2013); Oregon v. Mitchell, 400 U.S. 112, 132
(1970) (opinion of Black, J.) (relying on the “long history of the discriminatory use of literacy tests to disfranchise
voters on account of their race” to uphold congressional ban on literacy tests for voting).
228 See, e.g., Lane, 541 U.S. at 522–23 (observing that Title II of the ADA targets both “irrational disability
discrimination” and rights, like access to the courts under the Due Process Clause, that are “subject to more searching
judicial review”).
229 Compare Kimel v. Fla. Bd. of Regents, 528 U.S. 62, 83 (2000) (holding that Congress’s purported abrogation under
the Age Discrimination in Employment Act was invalid in part because “[s]tates may discriminate on the basis of age
without offending the Fourteenth Amendment if the age classification in question is rationally related to a legitimate
state interest”), with Hibbs, 538 U.S. at 728 (holding that Congress validly abrogated state sovereign immunity
pursuant to FMLA family-care leave provisions in part because “statutory classifications that distinguish between
males and females are subject to heightened scrutiny”).
230 Coleman v. Ct. of Appeals of Md., 566 U.S. 30, 37 (2012). For example, the Court in Allen v. Cooper found the
Copyright Remedy Clarification Act did not validly abrogate state sovereign immunity to copyright infringement suits
in part because the remedy Congress provided was “out of proportion” because it was not tailored to actual
constitutional violations. Allen v. Cooper, 140 S. Ct. 994, 1005–07 (2020); see also CRS Legal Sidebar LSB10356,
Piracy, Old and New: Copyright, State Sovereignty, and the Queen Anne’s Revenge, by Kevin J. Hickey.
231 See, e.g., City of Boerne v. Flores, 521 U.S. 507, 535 (1997), superseded by statute in part, Religious Land Use and
Institutionalized Persons Act of 2000 (RLUIPA), P.L. 106-274, 114 Stat. 803 (codified at 42 U.S.C. § 2000cc).
(“[RFRA] is broader than is appropriate if the goal is to prevent and remedy constitutional violations.”).
232 U.S. CONST. art. I, § 8, cl. 18; see generally Cong. Rsch. Serv., Overview of Necessary and Proper Clause,
CONSTITUTION ANNOTATED, https://constitution.congress.gov/browse/essay/artI-S8-C18-1/ALDE_00001242/ (last
visited Dec. 13, 2022).
233 Although “Necessary and Proper Clause” is the modern term for this constitutional provision, historically it was
often called the “Sweeping Clause.” See, e.g., THE FEDERALIST No. 33 (Alexander Hamilton); John Mikhail, The
Necessary and Proper Clauses
, 102 GEO. L.J. 1045, 1059 & n. 47 (2014) (“[The Framers] referred to the last clause of
Article I, Section 8 as the ‘Sweeping Clause.’”).
234 See Kinsella v. United States ex rel. Singleton, 361 U.S. 234, 247 (1960) (“The [Necessary and Proper Clause] is not
itself a grant of power, but a caveat that the Congress possesses all the means necessary to carry out the specifically
granted ‘foregoing’ powers of [Article I, Section 8] ‘and all other Powers vested by this Constitution.... ”). But see
Alison L. LaCroix, The Shadow Powers of Article I, 123 YALE L.J. 2044, 2062–67 (2014) (arguing that the Necessary
and Proper Clause is most accurately characterized as a separate enumerated power, even if “it is auxiliary rather than
Congressional Research Service

22

link to page 25 Federalism-Based Limitations on Congressional Power: An Overview

implicitly, when a court addresses the outer limits of Congress’s power under, for example, the
Commerce Clause, it necessarily considers the challenged statute’s validity under the Necessary
and Proper Clause, as well.235 In a few cases, however, the Supreme Court has analyzed
Congress’s power under the Necessary and Proper Clause independently from any specific
enumerated power. Typically, these cases involve either multiple enumerated powers,236 or
congressional actions that are many steps removed from the exercise of the underlying
enumerated federal power.237 Because the extent of the Necessary and Proper Clause defines the
outer reaches of Congress’s legislative powers, these cases delineate the boundary between the
authority of the federal government and those areas reserved to the states by the Tenth
Amendment.238
The Supreme Court’s 1819 opinion in McCulloch v. Maryland provides the canonical
interpretation of the Necessary and Proper Clause.239 McCulloch resolved the then-controversial
issue of whether Congress had the power to incorporate a national bank.240 Because the
enumerated powers of Article I do not explicitly include the power to establish a bank, McCulloch
addressed whether creating a national bank was a necessary and proper means of carrying out
Congress’s powers “to lay and collect taxes; to borrow money; to regulate commerce; to declare
and conduct a war; and to raise and support armies and navies.”241 The decision ultimately hinged
on how broadly to construe the Necessary and Proper Clause. McCulloch emphatically rejected
the argument that Congress’s implied powers under the clause are limited to those that are
“indispensibl[e]” or “absolutely” necessary.242 Rather, the Court held that “necessary” was better
understood to mean “conducive to” or “needful.”243 As the Court concluded, “Let the end be
legitimate, let it be within the scope of the constitution, and all means which are appropriate,
which are plainly adapted to that end, which are not prohibited, but consist with the letter and
spirit of the constitution, are constitutional.”244

primary”).
235 See, e.g., Gonzales v. Raich, 545 U.S. 1, 5 (2005) (addressing whether the prohibition of local use and cultivation of
marijuana was necessary and proper to Congress’s power to regulate interstate commerce); Missouri v. Holland, 252
U.S. 416, 432 (1920) (“If the treaty is valid there can be no dispute about the validity of the statute under Article 1, § 8,
as a necessary and proper means to execute the powers of the Government.”).
236 See, e.g., McCulloch v. Maryland, 17 U.S. (4 Wheat.) 316, 407 (1819) (considering whether Congress’s powers “to
lay and collect taxes; to borrow money; to regulate commerce; to declare and conduct a war; and to raise and support
armies and navies” implied the power to establish a national bank under the Necessary and Proper Clause).
237 See, e.g., United States v. Comstock, 560 U.S. 126, 148 (2010) (considering whether “the enumerated power that
justifies the creation of a federal criminal statute” further justifies indefinite civil commitment of a federal prisoner
after the expiration of their criminal sentence).
238 See J. Randy Beck, The New Jurisprudence of the Necessary and Proper Clause, 2002 U. ILL. L. REV. 581, 584
(2002) (“Because the Necessary and Proper Clause delineates the outer boundary of congressional authority,
interpretation of that provision also permits identification of reserved state powers.”); Stephen Gardbaum, The
Federalism Implications of
Flores, 39 WM. & MARY L. REV. 665, 682 (1998) (“[T]he Necessary and Proper Clause
. . . operates at the boundaries of federal and reserved state power.... ”).
239 LaCroix, supra note 234, at 2061 (describing McCulloch as “the lodestar for understanding the [Necessary and
Proper] clause”); Stephen Gardbaum, Rethinking Constitutional Federalism, 74 TEX. L. REV. 795, 814 (1996)
(“Analysis of the Necessary and Proper Clause has historically begun and ended with McCulloch.... ”).
240 McCulloch, 17 U.S. (4 Wheat.) at 401.
241 Id. at 406–07.
242 Id. at 414–17.
243 Id. at 418.
244 Id. at 421.
Congressional Research Service

23

Federalism-Based Limitations on Congressional Power: An Overview

Many federal laws rest on the foundation established by McCulloch’s broad interpretation of the
Necessary and Proper Clause. For example, “the Necessary and Proper Clause provides the
constitutional authority for most federal criminal statutes.”245 The Constitution expressly
empowers Congress to punish only four crimes: counterfeiting, piracies, offenses against the law
of nations, and treason.246 The rest of the federal criminal code—including prohibitions on tax
evasion, racketeering, mail fraud, drug possession, and other crimes247—rests on a determination
that criminalization is necessary to effectuate congressional power to regulate interstate
commerce, collect taxes, establish post offices, spend for the general welfare, or some other
enumerated federal power.248
Since McCulloch, the Supreme Court has continued to follow an expansive interpretation of the
Necessary and Proper Clause, holding that the Clause permits any federal legislation that is
“convenient” or “useful” to the exercise of federal power and is thereby “rationally related to the
implementation of a constitutionally enumerated power.”249 The leading modern case interpreting
the clause is United States v. Comstock. Comstock concerned a federal law providing for
indefinite civil commitment of certain persons in federal custody who were shown to be “sexually
dangerous,” even after those prisoners had served their federal sentences.250 The difficulty with
the law, as a matter of congressional power, was that the offenders’ sexual dangerousness did not
have an explicit tie to any specific enumerated federal power.251 As the Court previously held in
United States v. Morrison, Congress cannot regulate general sexual violence under the Commerce
Clause.252
Comstock nonetheless upheld the civil commitment provision under the Necessary and Proper
Clause. Writing for the majority, Justice Breyer held that whichever enumerated power justified
the prisoner’s crime of conviction253 also permitted Congress “to provide appropriately for those
imprisoned, and to maintain the security of those who are not imprisoned but who may be
affected by the federal imprisonment of others,” including through post-sentence civil

245 United States v. Comstock, 560 U.S. 126, 156 (2010) (Alito, J., concurring in the judgment).
246 See U.S. CONST. art. I, § 8, cls. 6, 10; id. art. III, § 3, cl. 2.
247 See, e.g., 18 U.S.C. §§ 1341–1351 (mail fraud and wire fraud); id. §§ 1951–1968 (racketeering); 21 U.S.C. § 844
(drug possession); 27 U.S.C. § 7201 (tax evasion).
248 See Comstock, 560 U.S. at 156 (Alito, J., concurring in the judgment) (“[M]ost federal criminal statutes rest upon a
congressional judgment that, in order to execute one or more of the powers conferred on Congress, it is necessary and
proper to criminalize certain conduct.... ”).
249 Id. at 133–34 (opinion of the Court) (citations omitted).
250 Id. at 130–31. For a fuller analysis of the Comstock decision, see CRS Report R40958, United States v. Comstock:
Legislative Authority Under the Necessary and Proper Clause
, by Charles Doyle.
251 See 18 U.S.C. § 4247(a)(6) (defining a “sexually dangerous person” as one who “suffers from a serious mental
illness ... as a result of which he would have serious difficulty in refraining from sexually violent conduct or child
molestation if released”).
252 529 U.S. 598, 617 (2000) (holding that Congress may not regulate “noneconomic, violent criminal conduct based
solely on that conduct’s aggregate effect on interstate commerce”).
253 Notably, the civil commitment provisions applied to any person in federal custody, regardless of whether his
conviction was for a sex-related crime or not. See 18 U.S.C. §§ 4247(a)(5), 4248(a). In practice, however, many of the
individuals committed under the statute were in federal custody for a sex crime that fell within federal jurisdiction, such
as possession of child pornography that “has been shipped or transported in or affecting interstate or foreign commerce
... by any means including by computer.” See id. § 2252(a)(2); Comstock, 560 U.S. at 131 (“Three of the five
[petitioners] had previously pleaded guilty in federal court to possession of child pornography . . . .”).
Congressional Research Service

24

link to page 12 Federalism-Based Limitations on Congressional Power: An Overview

commitment.254 The Court concluded that the following five factors rendered the challenged law a
valid exercise of Congress’s Necessary and Proper Clause authority:
(1) the breadth of the Necessary and Proper Clause, (2) the long history of federal
involvement in this arena, (3) the sound reasons for the statute’s enactment in light of the
Government’s custodial interest in safeguarding the public from dangers posed by those in
federal custody, (4) the statute’s accommodation of state interests, and (5) the statute’s
narrow scope.255
A few years later, the Supreme Court reaffirmed Comstock’s broad reading of the Necessary and
Proper Clause in United States v. Kebodeaux.256 Kebodeaux concerned another federal regulation
of sex offenders: the registration requirements of SORNA.257 Anthony Kebodeaux, a member of
the U.S. Air Force, was convicted by a court martial of a sex crime in 1999; he served a three-
month sentence and received a bad conduct discharge.258 In 2007, Kebodeaux was convicted of
violating SORNA when he moved from El Paso to San Antonio but failed to update his
registration.259 Although Congress had not enacted SORNA until well after Kebodeaux’s court
martial and discharge, the Supreme Court upheld SORNA’s application to Kebodeaux as
necessary and proper to Congress’s power to “make Rules for the ... Regulation of the land and
naval Forces.”260 Key to that conclusion was the Court’s finding that Kebodeaux’s release from
federal custody was not “unconditional” because he was subject to an earlier federal statute, the
Wetterling Act (P.L. 103-322, tit. XVII) which imposed “very similar” registration requirements
to those of SORNA.261 The Court explained that, as applied to Kebodeaux, the Wetterling Act was
necessary and proper to Congress’s power to regulate the military because it was imposed as part
of Kebodeaux’s original punishment by the court martial.262 The Court thus framed the case as
presenting a narrow question of whether Congress could later “modify” those registration
requirements through SORNA.263 Applying the five Comstock factors discussed above, the Court
found that the breadth of the Necessary and Proper Clause and the reasonableness of Congress’s
registration requirements justified SORNA’s application to Kebodeaux.264
Though Comstock and Kebodeaux embrace a broad understanding of the Necessary and Proper
Clause, Congress’s powers under this provision are not unlimited. For example, as discussed in
the “Regulating Activities that Substantially Affect Interstate Commerce” section above, the
Supreme Court has held that federal laws forbidding gun possession near schools, creating a civil
remedy for victims of gender-motivated violence, and compelling the purchase of health
insurance are not necessary and proper to the exercise of Congress’s power to regulate interstate
commerce.265 In addition, the Court has explained its view that Congress may not rely on the

254 Comstock, 560 U.S. at 149.
255 Id.
256 570 U.S. 387 (2013).
257 See 34 U.S.C. §§ 20911–20932; 18 U.S.C. § 2250(a).
258 Kebodeaux, 570 U.S. at 389–90.
259 Id. at 390.
260 U.S. CONST. art. I, § 8, cl. 14; Kebodeaux, 570 U.S. at 399.
261 Kebodeaux, 570 U.S. at 391.
262 Id. at 393.
263 Id. at 393–94.
264 See id. at 395–99.
265 See supra “Commerce Clause.”
Congressional Research Service

25

Federalism-Based Limitations on Congressional Power: An Overview

Necessary and Proper Clause to evade an “affirmative limitation” within an enumerated power,
such as the Bankruptcy Clause’s requirement that federal bankruptcy laws be “uniform.”266
Even so, following Comstock and Kebodeaux, lower courts have generally been deferential to
Congress’s power under the Necessary and Proper Clause. Many of these cases address various
as-applied challenges to SORNA; the courts of appeals have repeatedly rejected such challenges,
even when the defendant “neither served in the military, nor committed an offense or lived on
federal property, nor moved within interstate or foreign commerce.”267 Courts have likewise
relied on the Necessary and Proper Clause to uphold, for example, Congress’s power to
criminalize hostage taking;268 exercise supplemental jurisdiction over state law claims;269
criminalize theft from organizations receiving federal funds;270 criminalize bribery of state and
local officials receiving federal funds;271 provide for the death penalty for federal crimes;272
establish military commissions to try conspiracy to commit war crimes;273 and criminalize sexual
abuse in federal prisons.274
Federalism Limitations Based on the Tenth and
Eleventh Amendments
Along with the limitations derived from Congress’s enumerated powers, the Supreme Court has
recognized federalism doctrines that affirmatively prohibit Congress from taking certain actions,
even when Congress would otherwise be authorized to act under an enumerated power. Under
these doctrines, an act of Congress may be unconstitutional “not because Congress lacked
legislative authority over the subject matter, but because those statutes violated the principles of
federalism.”275 The specific textual source of these doctrines is not always clear.276 The Court has

266 See Siegel v. Fitzgerald, 142 S. Ct. 1770, 1779 (2022) (quoting Ry. Lab. Execs. Ass’n v. Gibbons, 455 U.S. 457,
468–69 (1982)).
267 United States v. Thompson, 811 F.3d 717, 723 (5th Cir. 2016) (collecting cases). See also, e.g., United States v.
Brune, 767 F.3d 1009, 1017 (10th Cir. 2014) (rejecting as-applied challenge to SORNA); United States v. Coppock, 765
F.3d 921, 925 (8th Cir. 2014) (same); United States v. Elk Shoulder, 738 F.3d 948, 957–59 (9th Cir. 2013) (same);
United States v. Carel, 668 F.3d 1211, 1218–24 (10th Cir. 2011) (same).
268 See, e.g., United States v. Mikhel, 889 F.3d 1003, 1023–24 (9th Cir. 2018) (upholding Hostage Taking Act as
necessary and proper to Congress’s Treaty Power); United States v. Shibin, 722 F.3d 233, 247 (4th Cir. 2013) (same);
United States v. Ferreira, 275 F.3d 1020, 1027–28 (11th Cir. 2001) (same).
269 See Artis v. Dist. of Columbia, 138 S. Ct. 594, 606–07 (2018) (rejecting argument that tolling the statute of
limitations for any state-law claim joined with a claim in federal court under supplemental jurisdiction would exceed
Congress’s power under the Necessary and Proper Clause).
270 See United States v. Edgar, 304 F.3d 1320, 1325–27 (11th Cir. 2002) (upholding 18 U.S.C. § 666(a)(1) as necessary
and proper to Congress’s Spending Power).
271 See Sabri v. United States, 541 U.S. 600, 606 (2004) (upholding 18 U.S.C. § 666(a)(2) as necessary and proper to
Congress’s Spending Power).
272 United States v. Aquart, 912 F.3d 1, 57–60 (2d Cir. 2018).
273 Al Bahlul v. United States, 840 F.3d 757, 758 (D.C. Cir. 2016) (per curiam); see also id. at 761–62 (Kavanaugh, J.,
concurring).
274 United States v. Mujahid, 799 F.3d 1228, 1233–35 (9th Cir. 2015).
275 Reno v. Condon, 528 U.S. 141, 149 (2000).
276 See, e.g., New York v. United States, 505 U.S. 144, 156–57 (1992) (“The Tenth Amendment likewise restrains the
power of Congress, but this limit is not derived from the text of the Tenth Amendment itself.... Instead, the Tenth
Amendment confirms that the power of the Federal Government is subject to limits that may, in a given instance,
reserve power to the States.”).
Congressional Research Service

26

link to page 30 link to page 34 link to page 41 link to page 7 link to page 9 Federalism-Based Limitations on Congressional Power: An Overview

often described the doctrines as based on the general constitutional principles as confirmed by the
Tenth Amendment277 (which reserves powers not granted to the federal government to the states
or the people) or the Eleventh Amendment278 (which prevents federal courts from hearing certain
lawsuits against states).
This section reviews three of these federalism doctrines: the anticommandeering doctrine,279 the
Eleventh Amendment and state sovereign immunity,280 and the equal sovereignty doctrine.281
The Anticommandeering Doctrine
As discussed above, Congress retains the power to encourage states and localities to adopt or
enforce federal policies by paying them to do so pursuant to its Spending Clause authority.282 The
“anticommandeering” doctrine, however, generally prohibits the federal government from
requiring states and localities to adopt or enforce federal policies.283 Much like the anti-coercion
limitation on Congress’s spending power,284 the anticommandeering doctrine derives from the
“fundamental structur[e]” of the Constitution, which “withholds from Congress the power to
issue orders directly to the States” and reserves all legislative power not granted to Congress to
the states via the Tenth Amendment.285
The anticommandeering doctrine has its origins in the Court’s 1992 decision in New York v.
United States
, which struck down a provision of a federal statute that required states to either
(1) regulate low-level radioactive waste generated within their borders according to the
instructions of Congress, or (2) take title to and possession of such waste.286 In striking down the
provision, the Court reasoned that, in light of both the absence of an enumerated constitutional
power to issue commands to state governments and the Tenth Amendment’s reservation of state
sovereignty, Congress may not “commandeer” or “conscript” state governments into
implementing federal policies by “directly compelling them to enact and enforce a federal
regulatory program.”287 The Court explained that this limitation on Congress’s authority “follows
from an understanding of the fundamental purpose served by our Government’s federal structure”

277 U.S. CONST. amend. X; see generally Cong. Rsch. Serv., Overview of the Tenth Amendment, Rights Reserved to the
States and the People,
CONSTITUTION ANNOTATED, https://constitution.congress.gov/browse/essay/amdt10-1/
ALDE_00013619/ (last visited Oct. 28, 2022).
278 U.S. CONST. amend. XI; see generally Cong. Rsch. Serv., Overview of the Eleventh Amendment, Suits Against
States
, CONSTITUTION ANNOTATED, https://constitution.congress.gov/browse/essay/amdt11-1/ALDE_00013675/ (last
visited Oct. 28. 2022).
279 See infra “The Anticommandeering Doctrine.”
280 See infra “The Eleventh Amendment and State Sovereign Immunity.”
281 See infra “Equal Sovereignty Doctrine.”
282 See supra “Spending Clause.”
283 Printz v. United States, 521 U.S. 898, 921, 929–30 (1997); New York v. United States, 505 U.S. 144, 175, 176–78
(1992).
284 See supra “The “Anti-Coercion” Doctrine.”
285 Murphy v. NCAA, 138 S. Ct. 1461, 1475 (2018). The Tenth Amendment provides that “[t]he powers not delegated
to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to
the people.” U.S. CONST. amend. X. See also NFIB v. Sebelius, 567 U.S. 519, 578 (2012) (explaining that “‘the
Constitution simply does not give Congress the authority to require the States to regulate,’” which “is true whether
Congress directly commands a State to regulate or indirectly coerces a State to adopt a federal regulatory system as its
own” (quoting New York, 505 U.S. at 178)) (opinion of Roberts, C.J.).
286 505 U.S. at 174–78.
287 Id. at 175, 176–78 (internal quotation marks and citation omitted).
Congressional Research Service

27

Federalism-Based Limitations on Congressional Power: An Overview

to “secure[] to citizens the liberties that derive from the diffusion of sovereign power.”288 The
Court also reasoned that the anticommandeering doctrine is necessary to ensure political
accountability because “[w]here the Federal Government directs the States to regulate, it may be
state officials who will bear the brunt of public disapproval, while the federal officials who
devised the regulatory program may remain insulated from the electoral ramifications of their
decision.”289
The Court again applied the anticommandeering doctrine five years later in Printz v. United
States
.290 In Printz, the Court struck down a provision of the Brady Handgun Violence Prevention
Act (P.L. 103-159) that required state law enforcement officers to perform background checks on
prospective gun purchasers.291 In striking down the challenged provision, the Court concluded
that Congress cannot require states to enforce or implement federal policies, even when the
relevant federal legislation merely requires state officials to perform “discrete, ministerial
tasks.”292 As in New York, the Court explained that this principle follows from the Constitution’s
“structural protections of liberty,” and that a contrary rule would diminish the political
accountability of government officials.293 The Court also gestured toward a related but separate
rationale for the anticommandeering doctrine, reasoning that allowing Congress to “forc[e] state
governments to absorb the financial burden of implementing a federal regulatory program” would
permit federal officials to “take credit for ‘solving’ problems without having to ask their
constituents to pay for the solutions with higher federal taxes.”294
The Supreme Court has explained that the anticommandeering doctrine recognized in New York
and Printz has important limits. First, the Court has held that the doctrine “does not apply when
Congress evenhandedly regulates an activity in which both States and private actors engage.”295
The Court invoked this exception to the anticommandeering doctrine in Reno v. Condon, where it
rejected a Tenth Amendment challenge to a federal law that restricted the states’ ability to disclose
personal information contained in their motor vehicle departments’ (DMVs’) records.296 The
Court upheld the challenged law—which also restricted the ability of private actors to disclose
personal information they obtained from state DMVs—because the law “regulate[d] the States as
the owners of databases,” but did not impinge states’ “sovereign capacity to regulate their own
citizens” by requiring the states to enact specific regulations or assist in the enforcement of
federal statutes regulating private individuals.297

288 Id. at 181 (internal quotation marks and citation omitted).
289 Id. at 169.
290 Printz v. United States, 521 U.S. 898, 917, 925, 929 (1997).
291 Id. at 935.
292 Id. at 929.
293 Id. at 921, 929–30.
294 Id. at 930.
295 Murphy v. NCAA, 138 S. Ct. 1461, 1478 (2018).
296 528 U.S. 141, 143–44, 151–52 (2000).
297 Id. at 151. In Condon, the Court relied in part on its 1988 decision in South Carolina v. Baker, which similarly
rejected a Tenth Amendment challenge to a statute removing a federal tax exemption for interest earned on state and
local bonds unless they were issued in registered (as opposed to bearer) form. 485 U.S. 505, 515 (1988). Operating
under the assumption that the challenged law “effectively prohibit[ed] issuing [bearer] bonds,” the Court upheld the
law on the grounds that it applied to both state governments and private corporations, and therefore did not “seek to
control or influence the manner in which States regulate private parties.” Baker, 485 U.S. at 514.
Congressional Research Service

28

Federalism-Based Limitations on Congressional Power: An Overview

Second, the anticommandeering doctrine does not prohibit Congress from requiring state courts
to enforce federal causes of action.298 The Court arrived at this conclusion in its 1947 decision in
Testa v. Katt, where it held that Rhode Island courts were required to enforce the federal
Emergency Price Control Act (P.L. 77-421).299 The act established a cause of action against
persons who sold certain goods above a prescribed price ceiling and provided that state courts
shared concurrent jurisdiction with federal courts to adjudicate claims brought under the act.300 In
Testa, the Court rejected the argument that Rhode Island courts were not required to enforce the
act because it was the statute of another sovereign, explaining that under the Supremacy Clause,
“the policy of the federal Act is the prevailing policy in every state.”301 Accordingly, while the
anticommandeering doctrine prohibits Congress from conscripting state legislatures and
executive officials to adopt or enforce federal policy, it does not prevent Congress from requiring
state courts to enforce federal causes of action.
Anticommandeering and Preemption
The anticommandeering doctrine is, as some courts have described, “intertwined”302 with the
concept of preemption, or the notion that Congress can displace (i.e., “preempt”) otherwise valid
but conflicting state laws under the Supremacy Clause.303 Whether an act of Congress has a valid
preemptive effect or instead impermissibly commandeers state legislatures had been difficult to
discern.304 In general, so long as the federal law at issue “represent[s] the exercise of a power
conferred on Congress by the Constitution,”305 and it regulates “individuals, not States,” the law

298 Testa v. Katt, 330 U.S. 386, 394 (1947).
299 Id.
300 Id. at 387.
301 Id. at 393.
302
Brackeen v. Haaland, 994 F.3d 249, 298 (5th Cir. 2021), cert. granted, 142 S. Ct. 1205 (Feb. 28, 2022) (No. 21-376).
303 U.S. CONST. art. VI, cl. 2. (“This Constitution, and the Laws of the United States which shall be made in Pursuance
thereof; and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme
Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any
State to the Contrary notwithstanding.”); Crosby v. Nat’l Foreign Trade Council, 530 U.S. 363, 372 (2000) (stating that
“[a] fundamental principle of the Constitution is that Congress has the power to preempt state law”); Altria Grp., Inc. v.
Good, 555 U.S. 70, 76 (2008) (noting that “we have long recognized that state laws that conflict with federal law are
‘without effect’”) (quoting Maryland v. Louisiana, 451 U.S. 725, 746 (1981)).
304 See Edward A. Hartnett, Distinguishing Permissible Preemption from Unconstitutional Commandeering, 96 NOTRE
DAME L. REV. 351, 351 (2020) (“For years, the preemption doctrine and the anticommandeering doctrine lived in an
uneasy tension, with each threatening to consume the other.”).
305 Murphy v. NCAA, 138 S. Ct. 1461, 1479 (2018). While the Court has not yet directly addressed Congress’s
Fourteenth Amendment powers in its anticommandeering decisions, other decisions arguably suggest (and a number of
commentators have assumed) that another “exception” to the anticommandeering doctrine exists in cases where
Congress acts pursuant to its power to enforce the Fourteenth Amendment “by appropriate legislation.” See U.S.
CONST. amend. XIV, § 5; Milliken v. Bradley, 433 U.S. 267, 291 (1977) (holding that the “Tenth Amendment’s
reservation of nondelegated powers to the States is not implicated by a federal-court judgment enforcing the express
prohibitions of unlawful state conduct enacted by the Fourteenth Amendment”); Fitzpatrick v. Bitzer, 427 U.S. 445,
456 (1976) (holding that the Fourteenth Amendment grants Congress the authority to abrogate the Eleventh
Amendment sovereign immunity of states on the grounds that, “when Congress acts pursuant to [Section 5 of the
Fourteenth Amendment], not only is it exercising legislative authority that is plenary within the terms of the
constitutional grant, it is exercising that authority under one section of a constitutional amendment whose other sections
by their own terms embody limitations on state authority”); Daniel Hemel, Murphy’s Law and Economics, MEDIUM
(May 16, 2018), https://medium.com/whatever-source-derived/murphys-law-and-economics-3c0974e21ac8 (explaining
that, under “a reasonable interpretation” of the Court’s anticommandeering cases, Congress can compel states to adopt
and enforce federal policies when it is “acting pursuant to its authority under the Reconstruction Amendments”);
Ronald D. Rotunda, The Doctrine of Conditional Preemption and Other Limitations on Tenth Amendment Restrictions,
Congressional Research Service

29

link to page 32 Federalism-Based Limitations on Congressional Power: An Overview

will have preemptive force and displaces any conflicting state laws.306 However, if the federal law
directly commands the executive or legislative branch of a state government to act or refrain from
acting in its “sovereign capacity to regulate [its] own citizens,” it violates the anticommandeering
doctrine.307
Prior to the Supreme Court’s 2018 decision Murphy v. NCAA, some considered the distinction
between permissible preemption and unconstitutional commandeering to be whether Congress
told the states what they could not do, versus Congress telling the states what they had to do.308 In
this situation, the “negative command was permissible preemption, while an affirmative
command was impermissible commandeering.”309 However, in Murphy, the Supreme Court
clarified that “[t]his distinction is empty” and that Congress may not issue direct orders to state
legislatures regardless of whether Congress is commanding “affirmative” action by the states or
imposing prohibitions on state conduct.310
The Court in Murphy further considered the relationship between commandeering and
preemption in its review of the federal Professional and Amateur Sports Protection Act of 1992
(PASPA; P.L. 102-559), which made it unlawful for most states to (among other things)
“authorize by law” sports gambling.311 In 2014, New Jersey enacted a statute partially repealing
its prohibition on sports gambling, allowing gambling to occur at most state casinos and
racetracks, but maintaining restrictions on gambling (1) at other locations, (2) on New Jersey
sporting events and collegiate teams, and (3) by persons under the age of 21.312 The National
Collegiate Athletic Association (NCAA) and other sports leagues challenged the New Jersey law
as an “authorization” of sports gambling that violated PASPA.313 In response, New Jersey argued
(among other things) that PASPA unconstitutionally commandeered state authority by prohibiting
it from repealing its ban on sports gambling.314
The Court sided with New Jersey and struck down PASPA’s prohibition of state “authorization”
of sports gambling under the anticommandeering doctrine.315 The Court concluded that this
provision in PASPA was unconstitutional because it “unequivocally dictate[d] what a state
legislature may and may not do,” and accordingly placed states “under the direct control of
Congress.”316 In arriving at this conclusion, the Court rejected the NCAA’s argument that
PASPA’s “anti-authorization” provision represented a valid exercise of Congress’s power to

132 U. PA. L. REV. 289, 298–99 (1984) (discussing the proposition that the Tenth Amendment’s limitations on
Congress’s authority do not apply when Congress legislates pursuant to its Fourteenth Amendment powers).
306 Murphy, 138 S. Ct. at 1479 (2018) (quoting New York v. United States, 505 U.S. 144, 166 (1992)). The
Constitution confers the power for Congress to regulate individuals, not states. Therefore, for a law to have preemptive
effect, it must regulate “private actors.” Id. The Supreme Court has held, however, that a law can still carry preemptive
effect if it regulates states that participate in an activity in which private parties engage. See id. at 1478–79 (“The
anticommandeering doctrine does not apply when Congress evenhandedly regulates an activity in which both States
and private actors engage.”) (citing Reno v. Condon, 528 U.S. 141 (2000)).
307 Condon, 528 U.S. at 151.
308 See Hartnett, supra note 304, at 351.
309 Id.
310 Murphy, 138 S. Ct. at 1478.
311 28 U.S.C. § 3702(1).
312 Murphy, 138 S. Ct. at 1472.
313 Id.
314 Id. at 1478.
315 Id.
316 Id.
Congressional Research Service

30

link to page 32 Federalism-Based Limitations on Congressional Power: An Overview

preempt state law.317 The Court rejected this argument on the grounds that “valid preemption”
occurs only when federal law is “best read as ... regulat[ing] private actors,” as opposed to state
governments.318 According to the Court, a federal statute is “best read as ... regulat[ing] private
actors” when it “imposes restrictions or confers rights on private actors,” thereby preempting state
laws that impose restrictions or confer rights that conflict with the federal statute.319 Because
PASPA’s “anti-authorization” provision did not “confer any federal rights on private actors
interested in conducting sports gambling operations” or “impose any federal restrictions on
private actors,” the Court concluded that it could not be interpreted “as anything other than a
direct command to the States,” which the anticommandeering doctrine forbids.320 Thus, some
have suggested that Murphy stands for the proposition that valid preemption requires Congress to
enact a law “that imposes restrictions or confers rights on private actors.”321 If a law confers
rights or imposes restrictions on a private actor, any state laws that conflict with those rights or
restrictions would be preempted by the federal law.322 If the law is “merely a direct command to
the states” it is unconstitutional commandeering.323
The Eleventh Amendment and State Sovereign Immunity
The Eleventh Amendment—which states that “the Judicial power of the United States shall not be
construed to extend to any suit in law or equity, commenced or prosecuted against one of the
United States by Citizens of another State, or by Citizens or Subjects of any Foreign State”—
establishes additional limitations on the federal government’s power in relation to the states.324
Subject to certain exceptions discussed below, if a private litigant initiates a lawsuit against a state
against that state’s wishes, the court must generally dismiss the case.325
The Eleventh Amendment implicates federalism because it limits the federal government’s ability
to regulate the states by restricting Congress’s authority to enact statutes that subject states to
suit.326 In the seminal 1890 case Hans v. Louisiana, the Supreme Court affirmed the principle that
states generally enjoy immunity from private suits arising under federal statutory or constitutional
law.327 Because judicial adjudication is the primary means by which the federal government may
enforce its legal mandates, the Eleventh Amendment insulates states from many types of lawsuits
to enforce federal laws and thus imposes significant constraints on the national government’s
power with regard to the states.328

317 Id. at 1479–81.
318 Id. at 1479.
319 Id. at 1480.
320 Id. at 1481.
321 See Hartnett, supra note 304, at 393.
322 Id.
323 Id.
324 U.S. CONST. amend. XI.
325 See, e.g., Colby v. Herrick, 849 F.3d 1273, 1281 (10th Cir. 2017) (“The Eleventh Amendment applies, foreclosing
suit against the Division. Thus, the district court was right to dismiss the claims against the Division.”).
326 See, e.g., Dellmuth v. Muth, 491 U.S. 223, 227 (1989), superseded by statute, Education of the Handicapped Act
Amendments of 1990, P.L. 101-476, 104 Stat. 1103 (codified at 20 U.S.C. § 1403), (discussing “principles of
federalism that inform Eleventh Amendment doctrine” (quoting Pennhurst State Sch. & Hosp. v. Halderman, 465 U.S.
89, 100 (1984))).
327 134 U.S. 1, 1–21 (1890).
328 See Louise Weinberg, Of Sovereignty and Union: The Legends of Alden, 76 NOTRE DAME L. REV. 1113, 1123
Congressional Research Service

31

Federalism-Based Limitations on Congressional Power: An Overview

The Court has interpreted the Eleventh Amendment against the broader background principle,
inherent in the Constitution’s structure, that the states, as separate and independent sovereigns,
enjoy immunity from suit.329 Thus, although the Supreme Court has “sometimes referred to the
States’ immunity from suit as ‘Eleventh Amendment immunity,’” that phrase is “something of a
misnomer, for the sovereign immunity of the States neither derives from, nor is limited by, the
terms of the Eleventh Amendment.”330 As the Supreme Court has explained, “each State is a
sovereign entity in our federal system,” and “it is inherent in the nature of sovereignty not to be
amenable to the suit of an individual without [the sovereign’s] consent.”331 According to the
Supreme Court, state sovereign immunity “serves two fundamental imperatives: safeguarding the
dignity of the states and ensuring their financial solvency.”332 As to the first of those two
principles, the Court has stated that “making one sovereign appear against its will in the courts
of” another sovereign—as would occur if a state were forced to litigate a case commenced against
it in federal court—would impinge the former sovereign’s dignity.333 The doctrine of state
sovereign immunity accordingly “confirms the sovereign status of the States by shielding them
from suits by individuals absent their consent.”334 With regard to the second principle, the
Supreme Court has emphasized that “the allocation of scarce resources among competing needs
and interests lies at the heart of the political process.”335 The Court has therefore reasoned that
granting “an unlimited congressional power to authorize suits” for monetary damages against the
states “would pose a severe and notorious danger to the States and their resources” and thereby
afford “Congress a power and a leverage over the States that is not contemplated by our
constitutional design.”336
Because “the Eleventh Amendment is but one particular exemplification of” the broader principle
of state sovereign immunity,337 the Supreme Court “has repeatedly held that the sovereign
immunity enjoyed by the States extends beyond the literal text of the Eleventh Amendment.”338
For instance, even though the text of the Eleventh Amendment would appear to apply only to
federal courts adjudicating lawsuits against states filed by citizens of another state or a foreign
state,339 the Supreme Court has nonetheless “extended the Amendment’s applicability to suits by

(2001) (opining that the Supreme Court’s Eleventh Amendment jurisprudence “frustrates judicial enforcement against
the states of federal constitutional and legal norms”).
329 See, e.g., Beaulieu v. Vermont, 807 F.3d 478, 483 (2d Cir. 2015) (“The concept of state sovereign immunity
encompasses different species of immunity. The Eleventh Amendment ... identifies a single species: immunity of a
state’s treasury from claims for damages brought by private entities in federal court ... States also enjoy a broader
sovereign immunity, which applies against all private suits, whether in state or federal court ... The Eleventh
Amendment is but one particular exemplification of that immunity.”) (internal citations, quotation marks, and ellipses
omitted).
330 Alden v. Maine, 527 U.S. 706, 713 (1999).
331 Seminole Tribe of Fla. v. Florida, 517 U.S. 44, 54 (1996) (quoting Hans, 134 U.S. at 13).
332 Karns v. Shanahan, 879 F.3d 504, 512 (3d Cir. 2018).
333 Pennhurst State Sch. & Hosp. v. Halderman, 465 U.S. 89, 100 (1984) (quoting Emps. of Dep’t of Pub. Health &
Welfare v. Dep’t of Pub. Health & Welfare, 411 U.S. 279, 294 (1973) (Marshall, J., concurring in the result)).
334 Frew ex rel. Frew v. Hawkins, 540 U.S. 431, 437 (2004).
335 Alden, 527 U.S. at 751.
336 Id. at 750.
337 E.g., Beaulieu v. Vermont, 807 F.3d 478, 483 (2d Cir. 2015).
338 See, e.g., Fed. Mar. Comm’n v. S.C. State Ports Auth., 535 U.S. 743, 754 (2002).
339 See U.S. CONST. amend. XI (“The Judicial power of the United States shall not be construed to extend to any suit in
law or equity, commenced or prosecuted against one of the United States by Citizens of another State, or by Citizens or
Subjects of any Foreign State
.”) (emphasis added). See also, e.g., Bd. of Trs. of Univ. of Ala. v. Garrett, 531 U.S. 356,
363 (2001) (“By its terms the Amendment applies only to suits against a State by citizens of another State.”).
Congressional Research Service

32

Federalism-Based Limitations on Congressional Power: An Overview

citizens against their own states.”340 Additionally, even though the text of the Eleventh
Amendment could be read to prohibit only suits against the states themselves,341 courts have
interpreted the amendment to also preclude lawsuits against certain state officials and state
agencies.342 The Eleventh Amendment, however, does not protect municipal entities.343
Similarly, even though the text of the Eleventh Amendment purports to limit only the power of
the federal courts,344 the Supreme Court has ruled that states also “retain immunity from private
suit in their own courts.”345 According to the Court, “an unlimited congressional power to
authorize suits in state court to levy upon the treasuries of the States” would undesirably give
“Congress a power and a leverage over the States that is not contemplated by our constitutional
design.”346 Relatedly, the Court has held that States retain their sovereign immunity from private
suits brought in the courts of other States.347
Further, although the Eleventh Amendment’s text appears to constrain only the “Judicial power
of the United States,”348 the Supreme Court has ruled that the doctrine of state sovereign
immunity generally prohibits federal administrative agencies from adjudicating disputes against
nonconsenting states.349
That is not to say, however, that states are categorically immune from suit. Even though courts
have interpreted the Eleventh Amendment more broadly than its language would suggest in some
ways, in other respects courts have interpreted the Eleventh Amendment more narrowly than its
text would suggest. In other words, even though the Eleventh Amendment states that the federal
judicial power “shall not be construed to extend to any suit ... commenced or prosecuted against
one of the United States,”350 the Supreme Court has nonetheless recognized circumstances in
which a court may validly adjudicate a lawsuit against a state.351

340 Garrett, 531 U.S. at 363 (emphasis added).
341 See U.S. CONST. amend. XI (“The Judicial power of the United States shall not be construed to extend to any suit in
law or equity, commenced or prosecuted against one of the United States by Citizens of another State, or by Citizens or
Subjects of any Foreign State.”) (emphasis added).
342 See, e.g., Regents of Univ. of Cal. v. Doe, 519 U.S. 425, 429 (1997) (“It has long been settled that the reference to
actions ‘against one of the United States’ encompasses not only actions in which a State is actually named as the
defendant, but also certain actions against state agents and state instrumentalities.”). As discussed below, courts have
recognized exceptions where it is permissible to sue a state official in his official capacity in federal court.
343 See Mt. Healthy City Sch. Dist. Bd. of Educ. v. Doyle, 429 U.S. 274, 280 (1977).
344 U.S. CONST. amend. XI (“The Judicial power of the United States shall not be construed to extend to any suit
. . . commenced or prosecuted against one of the United States ... ”) (emphasis added). See also Alden v. Maine, 527
U.S. 706, 730 (1999) (stating that “the fact that the Eleventh Amendment by its terms limits only ‘the Judicial power of
the United States’” does not delimit the Eleventh Amendment’s breadth).
345 Alden, 527 U.S. at 754 (emphasis added).
346 Id. at 750.
347 Franchise Tax Bd. of State of Cal. v. Hyatt, 139 S. Ct. 1485, 1492 (2019) (overruling Nevada v. Hall, 440 U.S. 410
(1979)).
348 U.S. CONST. amend. XI (emphasis added).
349 Fed. Mar. Comm’n v. S.C. State Ports Auth., 535 U.S. 743, 760 (2002) (“Simply put, if the Framers thought it an
impermissible affront to a State’s dignity to be required to answer the complaints of private parties in federal courts, we
cannot imagine that they would have found it acceptable to compel a State to do exactly the same thing before the
administrative tribunal of an agency.... The affront to a State’s dignity does not lessen when an adjudication takes place
in an administrative tribunal as opposed to an Article III court.”).
350 See U.S. CONST. amend. XI (emphasis added).
351 See Idaho v. Coeur d’Alene Tribe of Idaho, 521 U.S. 261, 267 (1997) (“[The text of the Eleventh Amendment]
could suggest that the Eleventh Amendment ... is cast in terms of reach or competence, so that the federal courts are
Congressional Research Service

33

Federalism-Based Limitations on Congressional Power: An Overview

First, the Supreme Court has recognized “that a State’s sovereign immunity is ‘a personal
privilege which it may waive at pleasure.’”352 Thus, a litigant may permissibly sue a state if that
state has voluntarily “allow[ed] a federal court to hear and decide a case commenced or
prosecuted against it.”353 Courts “will find a waiver” of a state’s Eleventh Amendment immunity
“either if the State voluntarily invokes [the court’s] jurisdiction, or else if the State makes a clear
declaration that it intends to submit itself to [the court’s] jurisdiction.”354 Significantly, the state’s
“consent to suit against it” must “be unequivocally expressed.”355 The Supreme Court has
therefore rejected the theory that a state may “‘impliedly’ or ‘constructively’” waive its sovereign
immunity by merely engaging in a field of interstate commerce that Congress has deemed fit to
regulate.356 However, under limited circumstances, Congress can incentivize a state to subject
itself to suit by “requir[ing] a waiver of state sovereign immunity as a condition for receiving
federal funds.”357 Congress must express its intent to condition the acceptance of federal funds on
the waiver of sovereign immunity “expressly and unequivocally” in the text of the relevant
statute.358 For example, because Congress has unambiguously required states to consent to suit
under the Individuals with Disabilities Education Act (IDEA; P.L. 104-476)359 as a condition of
receiving federal funds, several courts have ruled that private plaintiffs may sue certain state
educational departments and school boards under the IDEA if the state has accepted federal
financial assistance.360
Second, the Court has held that States may be sued if they “gave up their immunity from
congressionally authorized suits pursuant to the ‘plan of the [Constitutional] Convention’ as part

altogether disqualified from hearing certain suits brought against a State. This interpretation, however, has been neither
our tradition nor the accepted construction of the Amendment’s text.... The Amendment ... enacts a sovereign immunity
from suit, rather than a nonwaivable limit on the Federal Judiciary’s subject matter jurisdiction.”). There are also other
limited circumstances in which a litigant may hale a state into a federal court against its will that do not fit neatly within
the exceptions discussed below. See, e.g., S. Cent. Bell Tel. Co. v. Alabama, 526 U.S. 160, 165–66 (1999) (reaffirming
“that ‘[t]he Eleventh Amendment does not constrain the appellate jurisdiction of the Supreme Court over cases arising
from state courts’” to which the state is a party, even if the state objects to the Supreme Court adjudicating the case)
(quoting McKesson Corp. v. Div. of Alcoholic Beverages & Tobacco, 496 U.S. 18, 31 (1990)); California v. Deep Sea
Rsch. Inc., 523 U.S. 491, 494–95 (1998) (“The Eleventh Amendment does not bar the jurisdiction of a federal court
over an in rem admiralty action where the res is not within the State’s possession.”); Hess v. Port Auth. Trans-Hudson
Corp., 513 U.S. 30, 32–33 (1994) (recognizing that multi-state entities created pursuant to compacts between states are
ordinarily “not cloaked with the Eleventh Amendment immunity that a State enjoys” on its own).
352 Coll. Sav. Bank v. Fla. Prepaid Postsecondary Educ. Expense Bd., 527 U.S. 666, 675–87, 691 (1999) (quoting Clark
v. Barnard, 108 U.S. 436, 447 (1883)).
353 Coeur d’Alene Tribe, 521 U.S. at 267.
354 Coll. Sav. Bank, 527 U.S. at 675–76 (internal citations omitted).
355 Pennhurst State Sch. & Hosp. v. Halderman, 465 U.S. 89, 99 (1984) (internal citations omitted).
356 See Coll. Sav. Bank, 527 U.S. at 675–76.
357 E.g., Fryberger v. Univ. of Ark., 889 F.3d 471, 473 (8th Cir. 2018) (quoting Jim C. v. United States, 235 F.3d 1079,
1081 (8th Cir. 2000)). But see Hurst v. Tex. Dep’t of Assistive & Rehab. Servs., 482 F.3d 809, 811 (5th Cir. 2007) (“A
state’s receipt of federal funds does not automatically constitute a waiver of its Eleventh Amendment immunity.”);
Pace v. Bogalusa City Sch. Bd., 403 F.3d 272, 278 (5th Cir. 2005) (en banc) (applying “a five-prong test” to assess
whether Congress had validly “condition[ed] the availability of federal funds on a state’s waiver of its Eleventh
Amendment immunity”).
358 Sossamon v. Texas, 563 U.S 277, 290 (2011).
359 See 20 U.S.C. § 1403.
360 See, e.g., Pace, 403 F.3d at 275–89 (holding that, “when Louisiana accepted particular federal funds, it waived the
immunity afforded it by the Eleventh Amendment to suits under ... the IDEA”); A.W. v. Jersey City Pub. Schs., 341
F.3d 234, 236 (3d Cir. 2003) (holding that the New Jersey Department of Education and several of its officials had
“waived any immunity from” claims under the IDEA “by the acceptance of federal financial assistance.”).
Congressional Research Service

34

Federalism-Based Limitations on Congressional Power: An Overview

of ‘the structure of the original Constitution itself.’”361 In other words, congressional actions “do
not offend state sovereignty if ‘the States consented’ to them ‘at the founding.’”362 The Court has
recognized these “structural waiver[s]” in suits between states363 and in suits by the United States
against a state.364 The Court has also determined that when a federal power is “complete in itself”
and the states “consented to exercise of that power—in its entirety—in the plan of the
Convention,” that the states “implicitly agreed that their sovereignty ‘would yield to that of the
Federal Government.’”365 Therefore, the states “accepted upon ratification that their ‘consent,’
including to suit, could ‘never be a condition precedent to’ Congress’ chosen exercise of its
authority.”366 It follows then that, because the states have already consented to suit when
Congress acts pursuant to one of these powers, the states “have no immunity left to waive or
abrogate.”367 So far, the Court has recognized a “structural waiver” of state sovereign immunity in
three congressional powers found in the Constitution: the Bankruptcy Clause,368 the federal
eminent domain power,369 and the federal power to raise and support the Armed Forces.370
Third, in limited contexts, Congress may directly abrogate the states’ Eleventh Amendment
immunity by statute.371 However,
because abrogation of sovereign immunity upsets the fundamental constitutional balance
between the Federal Government and the States, and because States are unable directly to
remedy a judicial misapprehension of that abrogation, the [Supreme] Court has adopted a
particularly strict standard to evaluate claims that Congress has abrogated the States’
sovereign immunity.372
Thus, Congress may not “abrogate the States’ constitutionally secured immunity from suit in
federal court” unless it has made its intention to do so “unmistakably clear in the language of the
statute.”373 Under this reasoning, it is not enough for Congress to merely express an unequivocal
intent to abrogate the states’ Eleventh Amendment immunity;374 Congress must also “act[]

361 Torres v. Texas Dep’t of Pub. Safety, 142 S. Ct. 2455, 2460 (2022). See also Alden v. Maine, 527 U.S. 706, 730
(1999) (explaining that “States of the Union, still possessing attributes of sovereignty, shall be immune from suits,
without their consent, save where there has been ‘a surrender of this immunity in the plan of the convention’”).
362 Torres, 142 S. Ct. at 2462.
363 Id.; see, e.g., South Dakota v. North Carolina, 192 U.S. 286 (1904).
364 See, e.g., United States v. Texas, 143 U.S. 621 (1892). See also Principality of Monaco v. Mississippi, 292 U.S. 313,
329 (1934) (explaining that the jurisdiction over such parties was established by the States’ “own consent and delegated
authority as a necessary feature of the formation of a more perfect Union” and that, while the jurisdiction was not
“conferred by the Constitution in express words, it is inherent in the constitutional plan”).
365 Torres, 142 S. Ct. at 2463.
366 Id.
367 Id.
368 Cent. Va. Cmty. Coll. v. Katz, 546 U.S. 356 (2006).
369 PennEast Pipeline Co., LLC v. New Jersey, 141 S. Ct. 2244 (2021).
370 Torres, 142 S. Ct. at 2460.
371 See, e.g., Nat’l Ass’n of Bds. of Pharmacy v. Bd. of Regents of Univ. Sys. of Ga., 633 F.3d 1297, 1312 (11th Cir.
2011) (“Sovereign immunity is no bar to a claim for damages when Congress validly abrogates the States’ sovereign
immunity through legislation.”).
372 Port Auth. Trans-Hudson Corp. v. Feeney, 495 U.S. 299, 305 (1990) (internal citations and quotation marks
omitted).
373 Kimel v. Fla. Bd. of Regents, 528 U.S. 62, 73 (2000) (quoting Dellmuth v. Muth, 491 U.S. 223, 228 (1989),
superseded by statute
, Education of the Handicapped Act Amendments of 1990, P.L. 101-476, 104 Stat. 1103 (codified
at 20 U.S.C. § 1403)).
374 See, e.g., id. at 67 (concluding that, even though the Age Discrimination in Employment Act “contain[ed] a clear
Congressional Research Service

35

link to page 6 link to page 10 link to page 18 Federalism-Based Limitations on Congressional Power: An Overview

pursuant to a valid grant of constitutional authority” when it seeks to authorize suits against a
state in federal court.375
The Supreme Court has ruled that only a few of the constitutional grants of legislative power
discussed above376 provide a valid means for Congress to abrogate a state’s sovereign immunity.
In other words, “even when the Constitution vests in Congress complete lawmaking authority
over a particular area, the Eleventh Amendment” nevertheless generally “prevents congressional
authorization of suits by private parties against unconsenting States.”377 For instance, Congress
typically cannot “base its abrogation of the States’ Eleventh Amendment immunity upon the
powers enumerated in Article I” of the Constitution,378 such as the Commerce Clause379 or the
Intellectual Property Clause.380 Nonetheless, states may have already consented to suit under
some of Congress’s Article I powers through the “structural waivers” discussed above.
In addition, “Congress may authorize” litigants to sue a state in federal court “in the exercise of
[Congress’s] power to enforce the Fourteenth Amendment.”381 As discussed above,382 the
Fourteenth Amendment—which was “adopted well after the adoption of the Eleventh
Amendment and the ratification of the Constitution”—“alter[ed] the pre-existing balance between
state and federal power.”383 In particular, Section 5 grants Congress the “power to enforce, by
appropriate legislation,”384 constitutional protections that expressly constrain the states.385 The
Fourteenth Amendment therefore permits Congress to enact legislation that authorizes “private
suits against States or state officials which” might be “constitutionally impermissible in other
contexts.”386 Thus, for instance, the Supreme Court has concluded that Congress validly invoked
the Fourteenth Amendment to abrogate the states’ Eleventh Amendment immunity from certain
employment discrimination claims under the Civil Rights Act, or for violations of certain
provisions of the Family and Medical Leave Act.387 As the text of Section 5 stipulates, however,

statement of Congress’s intent to abrogate the States’ immunity,” the attempted “abrogation exceeded Congress’
authority under § 5 of the Fourteenth Amendment”).
375 Bd. of Trs. of Univ. of Ala. v. Garrett, 531 U.S. 356, 363 (2001) (quoting Kimel, 528 U.S. at 73).
376 See generally supra “Limitations on Congress’s Enumerated Powers.”
377 Kimel, 528 U.S. at 78 (quoting Seminole Tribe of Fla. v. Florida, 517 U.S. 44, 72 (1996)).
378 Garrett, 531 U.S. at 364.
379 E.g., Nev. Dep’t of Hum. Res. v. Hibbs, 538 U.S. 721, 727 (2003) (“Congress may not abrogate the States’
sovereign immunity pursuant to its Article I power over commerce.”). See generally supra “Commerce Clause.”
380 See, e.g., Allen v. Cooper, 140 S. Ct. 994, 1002 (2020) (explaining that, “[h]ere too, the power to ‘secure’ an
intellectual property owner’s ‘exclusive Right’ under Article I stops when it runs into sovereign immunity”). See also
U.S. CONST. art. I, § 8, cl. 8 (“The Congress shall have power ... to promote the progress of science and useful arts, by
securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries.”).
381 Coll. Sav. Bank v. Fla. Prepaid Postsecondary Educ. Expense Bd., 527 U.S. 666, 670 (1999) (emphasis added).
382 See supra “Congress’s Powers Under the Civil War Amendments.”
383 Seminole Tribe of Fla. v. Florida, 517 U.S. 44, 65–66 (1996).
384 U.S. CONST. amend. XIV, § 5.
385 See id. § 1 (“No state shall make or enforce any law which shall abridge the privileges or immunities of citizens of
the United States; nor shall any state deprive any person of life, liberty, or property, without due process of law; nor
deny to any person within its jurisdiction the equal protection of the laws.”) (emphasis added). Accord Fitzpatrick v.
Bitzer, 427 U.S. 445, 453 (1976) (“The substantive provisions of [the Fourteenth Amendment] are by express terms
directed at the States.”).
386 Fitzpatrick, 427 U.S. at 456.
387 Id. at 447; Nev. Dep’t of Hum. Res. v. Hibbs, 538 U.S. 721, 740 (2003).
Congressional Research Service

36

link to page 18 link to page 18 Federalism-Based Limitations on Congressional Power: An Overview

Congress may invoke the Fourteenth Amendment to abrogate a state’s immunity only if the
statute abrogating that immunity qualifies as “appropriate legislation.”388
Finally, notwithstanding the Eleventh Amendment, federal courts may generally adjudicate
lawsuits against individual state officers in their official capacity so long as the plaintiff seeks
only prospective injunctive389 or declaratory390 relief to remedy continuing violations of federal
statutory or constitutional law, as opposed to monetary damages.391 Federal courts may entertain
such lawsuits against state officials even though the state itself remains immune from suit.392 This
doctrine is known as the Ex Parte Young exception to Eleventh Amendment immunity, after the
landmark Supreme Court case in which the doctrine originated.393 Ex Parte Young “is based on
the notion, often referred to as ‘a fiction,’ that a State officer who” violates the U.S. Constitution
or a federal statute “is ‘stripped of his official or representative character’” for Eleventh
Amendment purposes.394 As a result, a lawsuit against that officer effectively constitutes a suit
against an individual rather than the state itself.395 The Supreme Court has justified this legal
fiction on the ground that “suits for declaratory or injunctive relief against state officers must ...
be permitted if the Constitution is to remain the supreme law of the land.”396 Ex Parte Young
thereby “ensures that state officials do not employ the Eleventh Amendment as a means of
avoiding compliance with federal law.”397
The Supreme Court has emphasized, however, that the Ex Parte Young exception “is narrow.”398
For one, Ex Parte Young applies only to suits against specific state officers in their official
capacities;399 the doctrine “has no application in suits against the States and their agencies, which

388 See, e.g., Kimel v. Fla. Bd. of Regents, 528 U.S. 62, 80 (2000). For a discussion of the types of statutes that
Congress may validly enact pursuant to Section 5 of the Fourteenth Amendment, see supra “Congress’s Powers Under
the Civil War Amendments.”

389 “Injunctive relief” is judicially granted relief “that has the quality of directing or ordering; of, relating to, or
involving an injunction.” BLACK’S LAW DICTIONARY (10th ed. 2014). An “injunction” is “a court order commanding or
preventing an action.” Id.
390 “Declaratory relief” is a “request to a court to determine the legal status or ownership of a thing.” Id. A “declaratory
judgment” is “a binding adjudication that establishes the rights and other legal relations of the parties.” Id.
391 See, e.g., Frew ex rel. Frew v. Hawkins, 540 U.S. 431, 437 (2004) (“The Eleventh Amendment permits suits for
prospective injunctive relief against state officials acting in violation of federal law.”); Green v. Mansour, 474 U.S. 64,
68 (1985) (“The Eleventh Amendment does not prevent federal courts from granting prospective injunctive relief to
prevent a continuing violation of federal law.”); Boler v. Earley, 865 F.3d 391, 412 (6th Cir. 2017) (“The exception set
forth in Ex Parte Young allows plaintiffs to bring claims for prospective relief against state officials sued in their
official capacity to prevent future federal constitutional or statutory violations.”); Balgowan v. New Jersey, 115 F.3d
214, 217 (3d Cir. 1997) (“The Ex Parte Young exception has been interpreted by courts to allow suits against state
officials for both prospective injunctive and declaratory relief. Although Ex Parte Young’s exact wording allows suits
for prospective injunctive relief, the 1908 opinion was issued well before declaratory relief was available.”) (emphasis
added; internal citations omitted). But see Town of Barnstable v. O’Connor, 786 F.3d 130, 138–39 (1st Cir. 2015)
(emphasizing that “Congress may render the Ex parte Young exception inapplicable by ‘prescrib[ing] a detailed
remedial scheme for the enforcement against a State of a statutorily created right’”) (quoting Seminole Tribe of Fla. v.
Florida, 517 U.S. 44, 74 (1996)).
392 E.g., Elephant Butte Irrigation Dist. of N.M. v. Dep’t of the Interior, 160 F.3d 602, 608 (10th Cir. 1998) (stating that
Ex Parte Young may apply “even if the state is immune”).
393 See Ex Parte Young, 209 U.S. 123 (1908).
394 Antrican v. Odom, 290 F.3d 178, 184 (4th Cir. 2002) (quoting Ex Parte Young, 209 U.S. at 160).
395 Id. (quoting Ex Parte Young, 209 U.S. at 160).
396 Alden v. Maine, 527 U.S. 706, 747 (1999).
397 P.R. Aqueduct & Sewer Auth. v. Metcalf & Eddy, Inc., 506 U.S. 139, 146 (1993).
398 Id. (internal citations omitted).
399 E.g., Boler v. Earley, 865 F.3d 391, 412 (6th Cir. 2017) (“The exception set forth in Ex Parte Young allows plaintiffs
Congressional Research Service

37

Federalism-Based Limitations on Congressional Power: An Overview

are barred regardless of the relief sought.”400 Additionally, plaintiffs cannot take advantage of the
Ex Parte Young exception if they seek any judicial remedy other than injunctive or declaratory
relief.401 Thus, Ex Parte Young does not authorize courts to “impose a liability which must be
paid from public funds in the state treasury,”402 such as monetary damages.403 Accordingly, “relief
that in essence serves to compensate a party injured in the past ... is barred even when the state
official is the named defendant.”404 Relatedly, plaintiffs may invoke Ex Parte Young only if they
seek prospective rather than retrospective relief.405 In other words, Ex Parte Young permits a
lawsuit against a state official only when “the relief ‘serves directly to bring an end to a present
violation of federal law.’”406 Relief under Ex Parte Young may also be foreclosed if Congress has
enacted a remedial scheme “specifically designed for enforcement of that right.”407 Finally, Ex
Parte Young
applies only when the plaintiff alleges that the defendant official is violating federal
law (including constitutional and statutory violations).408 The exception “does not apply when a
suit seeks relief under state law.”409
Equal Sovereignty Doctrine
In two recent voting rights cases, the Supreme Court has invoked the fundamental principle of
equal sovereignty as a limitation on congressional power.410 Because the United States “was and

to bring claims ... against state officials sued in their official capacity.”) (emphasis added). The Supreme Court has also
concluded that the Eleventh Amendment does not bar suits against individual officers in their personal capacities
pursuant to 42 U.S.C. § 1983, a federal statute that authorizes certain civil lawsuits against individual state officers
predicated upon alleged violations of federal constitutional or statutory law. Hafer v. Melo, 502 U.S. 21, 31 (1991).
400 P.R. Aqueduct, 506 U.S. at 146.
401 E.g., Mills v. Maine, 118 F.3d 37, 54 (1st Cir. 1997) (“Ex Parte Young allows a way around the bar to federal
jurisdiction erected by the Supreme Court’s Eleventh Amendment jurisprudence only in cases where prospective
declaratory or injunctive relief is sought.”).
402 Hafer, 502 U.S. at 30 (quoting Edelman v. Jordan, 415 U.S. 651, 663 (1974)).
403 E.g., Frew ex rel. Frew v. Hawkins, 540 U.S. 431, 437 (2004) (“Federal courts may not award ... money damages or
its equivalent[] if the State invokes its immunity.”). The Eleventh Amendment, however, does not bar monetary
sanctions payable out of the state treasury in Ex Parte Young actions. Hutto v. Finney, 437 U.S. 678, 691–92 (1978)
(explaining that attorney’s fees imposed for bad faith (much like remedial fines for civil contempt) are not barred by
“the substantive protections of the Eleventh Amendment”).
404 Papasan v. Allain, 478 U.S. 265, 278 (1986). That said, the Eleventh Amendment does not preclude “monetary
relief that is ‘ancillary’ to injunctive relief.” Kentucky v. Graham, 473 U.S. 159, 169 n.18 (1985). “A court may enter a
prospective injunction that costs the state money” as long as “the monetary impact is ... not the primary purpose of the
suit.” E.g., Barton v. Summers, 293 F.3d 944, 950 (6th Cir. 2002).
405 E.g., S & M Brands, Inc. v. Cooper, 527 F.3d 500, 508 (6th Cir. 2008) (“The Ex parte Young exception does not,
however, extend to any retroactive relief.”); Porter v. Jones, 319 F.3d 483, 491 (9th Cir. 2003) (“Under the doctrine of
Ex parte Young, suits against an official for prospective relief are generally cognizable, whereas claims for
retrospective relief (such as damages) are not.”). Courts have acknowledged, however, that “the distinction between
prospective and retroactive relief is not always easy to discern” in practice. Armstead v. Coler, 914 F.2d 1464, 1468
(11th Cir. 1990).
406 Town of Barnstable v. O’Connor, 786 F.3d 130, 138 (1st Cir. 2015) (quoting Whalen v. Mass. Trial Ct., 397 F.3d 19,
29 (1st Cir. 2005)).
407 Seminole Tribe of Fla. v. Florida, 517 U.S. 44, 74–76 (1996) (explaining that “where Congress has prescribed a
detailed remedial scheme for the enforcement against a State of a statutorily created right, a court should hesitate before
casting aside those limitations and permitting an action against a state office based upon Ex Parte Young”).
408 Papasan, 478 U.S. at 277.
409 E.g., Doe v. Regents of Univ. of Cal., 891 F.3d 1147, 1153 (9th Cir. 2018) (emphasis added).
410 Nw. Austin Mun. Util. Dist. No. One v. Holder, 557 U.S. 193, 203 (2009); Shelby Cnty. v. Holder, 570 U.S. 529,
544 (2013).
Congressional Research Service

38

Federalism-Based Limitations on Congressional Power: An Overview

is a union of states, equal in power, dignity and authority,”411 the equal sovereignty principle
limits Congress’s ability to enact legislation that subjects different states to unequal burdens, at
least without a sufficient justification.412
Whether the equal sovereignty principle is based on the Tenth Amendment, or some other
constitutional provision, is unclear from the Court’s cases. Although the Constitution explicitly
mandates equal treatment of states in some particular contexts,413 no provision of the Constitution
explicitly requires Congress to treat states equally as a general matter.414 In cases involving the
admission of new states, the Supreme Court in the 19th century developed the “equal footing”
doctrine,415 which generally requires that Congress admit new states on equal terms with the
original states.416 That doctrine forbids Congress from imposing “restrictions upon a new state
which deprive it of equality with other members of the Union.”417 Until 2009, the applicability of
that doctrine outside the state admission context was questionable, with the Court stating in the
1966 case South Carolina v. Katzenbach that “[t]he doctrine of the equality of States ... applies
only to the terms upon which States are admitted to the Union.”418
In Northwest Austin Municipal Utility District Number One v. Holder419 and Shelby County v.
Holder
,420 the Court applied the equal sovereignty principle more broadly. Both cases concerned
the constitutionality of Sections 4 and 5 of the Voting Rights Act of 1965 (VRA; P.L. 89-110). To
remedy the racial discrimination in voting endemic during the Jim Crow era, Section 4 of the
VRA contained a “coverage formula” identifying jurisdictions with a history of racial
discrimination against voters, whereas Section 5 required those jurisdictions to obtain
preclearance from the Department of Justice or a federal court before changing their voting
procedures.421 As a result, jurisdictions covered by Section 4 were subject to more stringent
requirements when seeking to change their voting laws, compared to other states.
Although the Court upheld the constitutionality of this arrangement in Katzenbach,422 Northwest
Austin
observed that the VRA’s preclearance requirements and coverage formula impose

411 Shelby Cnty., 570 U.S. at 544 (citing Coyle v. Smith, 221 U.S. 559, 567 (1911)).
412 Id. at 542 (“[A] departure from the fundamental principle of equal sovereignty requires a showing that a statute’s
disparate geographic coverage is sufficiently related to the problem that it targets.” (quoting Nw. Austin, 557 U.S. at
203)).
413 See, e.g., U.S. CONST. art. I, § 3, cl. 1 (“The Senate of the United States shall be composed of two Senators from
each State.... ”); U.S. CONST. art. I, § 8, cl. 1 (requiring “Duties, Imposts, and Excises” to be “uniform throughout the
United States”); U.S. Const. art. I, § 8, cl. 4 (requiring “an uniform Rule of Naturalization” and “uniform Laws on the
subject of Bankruptcies throughout the United States”); U.S. CONST. art. I, § 9, cl. 6 (“No Preference shall be given by
any Regulation of Commerce or Revenue to the Ports of one State over those of another.”).
414 See generally Leah M. Litman, Inventing Equal Sovereignty, 114 MICH. L. REV. 1207, 1230–32 (2016); Thomas
Colby, In Defense of the Equal Sovereignty Principle, 65 DUKE L.J. 1087, 1099 (2016).
415 See generally Cong. Rsch. Serv., ArtIV.S3.C1.3.1 The Equal Footing Doctrine Generally, CONSTITUTION
ANNOTATED, https://constitution.congress.gov/browse/essay/artIV-S3-C1-3-1/ALDE_00013710/ (last visited Nov. 8,
2022).
416 Pollard’s Lessee v. Hagan, 44 U.S. 212, 223 (1845).
417 Coyle v. Smith, 221 U.S. 559, 567 (1911).
418 South Carolina v. Katzenbach, 383 U.S. 301, 328–29 (1966) (citing Coyle, 221 U.S. 559).
419 557 U.S. 193, 203 (2009).
420 570 U.S. 529, 544 (2013).
421 Id. at 537–38.
422 Katzenbach, 383 U.S. at 328–83; accord Georgia v. United States, 411 U.S. 526 (1973); City of Rome v. United
States, 446 U.S. 156 (1980), superseded by statute, Voting Rights Act Amendments of 1982, P.L. 97-205, § 2(b), 96
Stat. 131 (codified at 42 U.S.C. § 1973b); Lopez v. Monterey Cnty., 525 U.S. 266 (1999).
Congressional Research Service

39

Federalism-Based Limitations on Congressional Power: An Overview

“substantial ‘federalism costs’”423 that have become tougher to justify given improved voting
conditions since 1965.424 The Court observed that the coverage formula, by differentiating
between the states, departs from “the fundamental principle of equal sovereignty,” raising
“serious constitutional questions.”425 Ultimately, however, the Court resolved Northwest Austin
on statutory grounds.426
Four years later, Shelby County resolved the constitutional question left open in Northwest Austin,
relying on the equal sovereignty principle to strike down the VRA’s coverage formula as
unconstitutional.427 Under the test used in Shelby County, “a departure from the fundamental
principle of equal sovereignty requires a showing that a statute’s disparate geographic coverage is
sufficiently related to the problem that it targets.”428 The Court observed that in the nearly 50
years since the VRA was first upheld in Katzenbach, “things have changed dramatically,”
pointing to increases in African American voter registration rates and turnout in covered
jurisdictions.429 Unlike the “exceptional conditions” present in Katzenbach, the Court found that
current conditions did not justify applying the preclearance formula to only certain states and
counties.430
The Court has not decided an equal sovereignty challenge since Shelby County, so it remains
unclear whether and how the doctrine will apply outside the voting rights context.431 Since Shelby
County
, only a handful of federal courts have considered equal sovereignty challenges, and none
has struck down a federal statute or action on those grounds.432 In Mayhew v. Burwell, for
example, the First Circuit considered an equal sovereignty challenge to a provision in the
American Recovery and Reinvestment Act of 2009 (ARRA; P.L. 111-5) that offered stimulus
funds to states that agreed to make no changes in their Medicaid coverage for 18- to 20-year-
olds.433 Maine initially accepted the funds and provided Medicaid coverage to this group, but later
determined that it wanted to change its policy.434 Maine argued that the ARRA provision locking
its Medicaid coverage policy in place violated the equal sovereignty principle under Shelby

423 Nw. Austin, 557 U.S. at 202 (quoting Lopez, 525 U.S. at 282).
424 Id. at 202 (“Things have changed in the South.”), 203 (“[T]he statute’s coverage formula is based on data that is
now more than 35 years old, and there is considerable evidence that it fails to account for current political conditions.”).
425 Id. at 203–04
426 Id. at 206–11.
427 Shelby Cnty. v. Holder, 570 U.S. 529, 557 (2013).
428 Id. at 542 (quoting Nw. Austin, 557 U.S. at 203).
429 Id. at 547–48.
430 Id. at 557.
431 A number of federal appeals courts have declined to extend Shelby County to contexts outside of voting rights, such
as the exercise of congressional power under the Thirteenth Amendment, absent a clearer indication from the Court.
See, e.g., United States v. Diggins, 36 F.4th 302, 317 (1st Cir. 2022); United States v. Roof, 10 F.4th 314, 394 (4th Cir.
2021); United States v. Cannon, 750 F.3d 492, 505 (5th Cir. 2014).
432 See, e.g., New York v. Yellen, 15 F.4th 569, 584 (2d Cir. 2021), cert. denied, 142 S. Ct. 1669 (2022) (rejecting claim
that cap on federal tax deduction for state and local taxes violated the principle of equal sovereignty); NCAA v.
Governor of N.J., 730 F.3d 208, 239 (3d Cir. 2013) (rejecting equal sovereignty challenge to a congressional regulation
of gambling that exempted Nevada, and questioning whether “the equal sovereignty principle applies in the same
manner in the context of Commerce Clause legislation”), abrogated on other grounds by Murphy v. NCAA, 138 S. Ct.
1461 (2018).
433 772 F.3d 80, 83–84 (1st Cir. 2014).
434 Id. at 84.
Congressional Research Service

40

Federalism-Based Limitations on Congressional Power: An Overview

County because it could not adopt a policy that other states had adopted, resulting in “disparate
treatment.”435
The First Circuit distinguished Shelby County and concluded that ARRA, unlike the VRA’s
coverage formula, did not involve unequal treatment of states by Congress.436 The court explained
that in the VRA cases, the formula defining the covered jurisdictions had been admittedly
“reverse engineered” to target certain jurisdictions, singling out particular states for disfavored
treatment.437 By contrast, the rule in ARRA was applied uniformly: “Congress came up with the
criteria without regard to which states would be covered by their application.”438 The First Circuit
also determined that the equal sovereignty doctrine applied only in “extraordinary situations,”
such as the VRA, involving a “sensitive area of state and local policymaking.”439 The ARRA’s
condition on Medicaid coverage did not, in the appellate court’s view, involve such an area.440
Alternatively, the First Circuit explained that any differential treatment of states was sufficiently
related to valid legislative purposes, as compared to the “decades-old data and eradicated
practices” used to justify the VRA’s coverage formula.441 As Mayhew and other lower court
decisions reflect, federal courts have largely limited the application of the equal sovereignty
doctrine to the voting rights context.
Conclusion
Whether based on interpretations of Congress’s enumerated powers, the Tenth and Eleventh
Amendments, or more general constitutional principles, the Supreme Court has established a
number of federalism-based doctrines that constrain Congress’s authority. Congress may wish to
consider these federalism-based limitations when legislating, to try to ensure that its enactments
comport with the Constitution and are less susceptible to judicial challenges.


Author Information

Kevin J. Hickey, Coordinator
Whitney K. Novak
Legislative Attorney
Legislative Attorney


Bryan L. Adkins
Jay B. Sykes
Legislative Attorney
Legislative Attorney



435 Id. at 93–94.
436 Id. at 94.
437 Id.
438 Id.
439 Id. at 94–95.
440 Id. at 95.
441 Id. at 96.
Congressional Research Service

41

Federalism-Based Limitations on Congressional Power: An Overview



Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan
shared staff to congressional committees and Members of Congress. It operates solely at the behest of and
under the direction of Congress. Information in a CRS Report should not be relied upon for purposes other
than public understanding of information that has been provided by CRS to Members of Congress in
connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not
subject to copyright protection in the United States. Any CRS Report may be reproduced and distributed in
its entirety without permission from CRS. However, as a CRS Report may include copyrighted images or
material from a third party, you may need to obtain the permission of the copyright holder if you wish to
copy or otherwise use copyrighted material.

Congressional Research Service
R45323 · VERSION 3 · UPDATED
42