Prosecutorial Discretion in Immigration Enforcement: Legal Issues
Abstract
[Excerpt] This report begins by discussing the sources of federal power to regulate immigration and,
particularly, the allocation of power between Congress and the President in this area. It next addresses the
constitutional and other foundations for the doctrine of prosecutorial discretion, as well as the potential ways
in which prosecutorial discretion may be exercised in the immigration context. It concludes by addressing
potential constitutional, statutory, and administrative constraints upon the exercise of prosecutorial
discretion. The report does not address other aspects of discretion in immigration law, such as the discretion
exercised by immigration officers in granting benefits (e.g., asylum), or by immigration judges in non-
enforcement contexts (e.g., cancellation of removal).
Keywords
immigration, enforcement, prosecution, discretion
Comments
Suggested Citation
Manuel, K. M. & Garvey, T. (2012). Prosecutorial discretion in immigration enforcement: Legal issues.
Washington, DC: Congressional Research Service.
A more recent version of this report can be found here: http://digitalcommons.ilr.cornell.edu/
key_workplace/1218
This article is available at DigitalCommons@ILR: http://digitalcommons.ilr.cornell.edu/key_workplace/992


Prosecutorial Discretion in Immigration
Enforcement: Legal Issues

Kate M. Manuel
Legislative Attorney
Todd Garvey
Legislative Attorney
January 17, 2013
Congressional Research Service
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www.crs.gov
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epared for Members and Committees of Congress

Prosecutorial Discretion in Immigration Enforcement: Legal Issues

Summary
The term prosecutorial discretion is commonly used to describe the wide latitude that prosecutors
have in determining when, whom, how, and even whether to prosecute apparent violations of the
law. The Immigration and Naturalization Service (INS) and, later, the Department of Homeland
Security (DHS) and its components have historically described themselves as exercising
prosecutorial discretion in immigration enforcement. Some commentators have recently
challenged this characterization on the grounds that DHS enforces primarily civil violations, and
some of its components cannot be said to engage in “law enforcement,” as that term is
conventionally understood. However, even agencies that do not prosecute or engage in law
enforcement have been recognized as having discretion (sometimes referred to as enforcement
discretion
) in determining whether to enforce particular violations.
Federal regulation of immigration is commonly said to arise from various powers enumerated in
the Constitution (e.g., naturalization, commerce), as well as the federal government’s inherent
power to control and conduct foreign relations. Some, although not all, of these powers belong
exclusively to Congress, and courts have sometimes described Congress as having “plenary
power” over immigration. However, few courts or commentators have addressed the separation of
powers between Congress and the President in the field of immigration, and the executive has
sometimes been said to share plenary power over immigration with Congress as one of the
“political branches.” Moreover, the authority to exercise prosecutorial or enforcement discretion
has traditionally been understood to arise from the Constitution, not from any congressional
delegation of power.
Certain decisions have been widely recognized as within the prosecutorial discretion of
immigration officers. These include deciding whether to initiate removal proceedings and what
charges to lodge against the respondent; canceling a Notice to Appear or other charging document
before jurisdiction vests with an immigration judge; granting deferred action or extended
voluntary departure to an alien otherwise subject to removal (deportation); appealing particular
decisions or orders; and imposing fines for particular offenses, among other things. Enforcement
priorities and resources, as well as humanitarian concerns, have typically played a role in
determining whether to exercise discretion in individual cases. For example, the George W. Bush
Administration temporarily suspended employer sanctions in areas affected by Hurricane Katrina,
and the Obama Administration recently began granting deferred action to certain unauthorized
aliens brought to the United States as children.
While the executive branch’s prosecutorial or enforcement discretion is broad, it is not unfettered,
and particular exercises of discretion could potentially be checked by the Constitution, statute, or
agency directives. Selective prosecution, or prosecution based on race, religion, or the exercise of
constitutional rights, is prohibited, although aliens generally cannot assert selective prosecution as
a defense to removal. A policy of non-enforcement that amounts to an abdication of an agency’s
statutory responsibilities could potentially be said to violate the Take Care Clause. However,
standing to challenge alleged violations of the Take Care Clause may be limited, and no court
appears to have invalidated a policy of non-enforcement founded upon prosecutorial discretion on
the grounds that the policy violated the Take Care Clause. Non-enforcement of particular laws
could also potentially be challenged under the Administrative Procedure Act if a statute provides
specific guidelines for the agency to follow in exercising its enforcement powers. In addition, an
agency could potentially be found to have constrained its own discretion, as some courts found
that the INS had done in the 1970s with its operating instruction on deferred action.
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Prosecutorial Discretion in Immigration Enforcement: Legal Issues

Contents
Introduction ...................................................................................................................................... 1
Federal Power to Regulate Immigration .......................................................................................... 3
Prosecutorial Discretion Generally .................................................................................................. 7
Prosecutorial Discretion in the Immigration Context .................................................................... 10
Potential Limits on the Exercise of Discretion .............................................................................. 13
Constitution ............................................................................................................................. 15
Selective Prosecution ........................................................................................................ 15
“Take Care” Clause ........................................................................................................... 16
Statute ...................................................................................................................................... 19
Whether “Shall” Means Agencies Lack Discretion .......................................................... 20
Deference to Agencies’ Interpretations of Their Governing Statutes ................................ 22
Executive Branch Self-Regulation .......................................................................................... 23
Conclusion ..................................................................................................................................... 25

Contacts
Author Contact Information........................................................................................................... 27

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Prosecutorial Discretion in Immigration Enforcement: Legal Issues

Introduction
The term prosecutorial discretion is commonly used to describe the “wide latitude” that
prosecutors have in determining when, whom, how, and even whether to prosecute apparent
violations of the law.1 The Immigration and Naturalization Service (INS) and, later, the
Department of Homeland Security (DHS) and its components have historically described
themselves as exercising prosecutorial discretion in the enforcement of federal immigration law,
which is largely contained in the Immigration and Nationality Act of 1952 (INA), as amended.2
Some commentators have recently challenged this characterization on the grounds that DHS
enforces primarily civil violations, and some of its components cannot be said to engage in “law
enforcement,” as that term is conventionally understood.3 However, even agencies that do not
prosecute or engage in law enforcement have been recognized as having discretion (sometimes
referred to as enforcement discretion) in determining whether to enforce particular violations,4
and immigration officers appear to have exercised such discretion in individual cases and on a
categorical basis for decades. For example, the Kennedy Administration granted extended
voluntary departure to persons from Cuba in 1960,5 allowing many otherwise deportable Cuban
nationals to remain in the United States for an extended period, while the George W. Bush
Administration temporarily suspended employer sanctions on entities that employed unauthorized
aliens in areas affected by Hurricane Katrina.6
The scope of prosecutorial discretion in immigration enforcement has recently been of interest to
Congress and the public due to certain initiatives of the Obama Administration.7 In 2011, John

1 U.S. Dep’t of Justice, United States Attorneys’ Manual, §9-27.110(B) (2002), available at http://www.justice.gov/
usao/eousa/foia_reading_room/usam/title9/27mcrm.htm#9-27.110.
2 See, e.g., Julie L. Myers, Assistant Secretary, U.S. Immigration and Customs Enforcement (ICE), Prosecutorial and
Custody Detention, Nov. 7, 2007, available at http://iwp.legalmomentum.org/reference/additionalmaterials/
immigration/enforcement-detention-and-criminal-justice/governmentdocuments/
Myers%20Memo%20Custody%20Discretion%2011-7-07.pdf/view (“This memorandum serves to highlight the
importance of exercising prosecutorial discretion when making administrative arrest and custody determinations for
aliens who are nursing mothers.”); Doris Meissner, Commissioner, INS, Exercising Prosecutorial Discretion, Nov. 7,
2000, available at http://iwp.legalmomentum.org/reference/additional-materials/immigration/enforcement-detention-
and-criminal-justice/government-documents/22092970-INS-Guidance-Memo-Prosecutorial-Discretion-Doris-
Meissner-11-7-00.pdf/view [hereinafter “2002 INS Guidance”] (“This memorandum describes the principles with
which the INS exercises prosecutorial discretion and the process to be followed in making and monitoring discretionary
decisions.”). INS was abolished in 2002, and most of its functions were transferred to the newly created Department of
Homeland by the Homeland Security Act of 2002 (P.L. 107-296).
3 See, e.g., Crane v. Napolitano, No. 3:12-cv-03247-O, Amended Complaint (filed N.D. Tex., Oct. 10, 2012), at ¶¶ 88-
89 (“U.S. Citizenship and Immigration Services is not a law enforcement agency. A non-law-enforcement agency
cannot exercise prosecutorial discretion.”): Robert J. Delahunty & John C. Yoo, The Obama Administration, the
DREAM Act, and the Take Care Clause, at 3, available at http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2144031
(noting that immigration laws are primarily enforced civilly).
4 See, e.g., Heckler v. Chaney, 470 U.S. 821, 831 (1985) (“[W]e recognize that an agency’s refusal to institute
proceedings shares to some extent the characteristics of the decision of a prosecutor in the Executive Branch not to
indict—a decision which has long been regarded as the special province of the Executive Branch, inasmuch as it is the
Executive who is charged by the Constitution to ‘take Care that the Laws be faithfully executed.’”).
5 See, e.g., Lynda J. Oswald, Extended Voluntary Departure: Limiting the Attorney General’s Discretion in
Immigration Matters
, 85 MICH. L. REV. 152, 158 n.40 (1986).
6 U.S. Dep’t of Homeland Security, Press Release, Notice Regarding I-9 Documentation Requirements for Hiring
Hurricane Victims, Sept. 6, 2005, available at http://v2011.nilc.org/disaster_assistance/FINAL_I-9_Press_Release.pdf.
7 The Obama Administration has also recently cited prosecutorial discretion in abstaining from prosecutions for
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Morton, the Director of U.S. Customs and Immigration Enforcement (ICE), issued two
memoranda addressing prosecutorial discretion, one of which identified ICE’s priorities for the
apprehension, detention, and removal of aliens,8 and the other of which discussed how ICE
personnel may exercise prosecutorial discretion consistent with ICE’s enforcement priorities.9
Subsequently, in June 2012, Secretary of Homeland Security Janet Napolitano issued a
memorandum “setting forth how, in the exercise of [its] prosecutorial discretion, the Department
... should enforce the Nation’s immigration laws against certain young people who were brought
to this country as children and know only this country as home.”10 As implemented, this initiative
has come to be known as Deferred Action for Childhood Arrivals (DACA). Most recently, DHS
has clarified that family ties between long-term, same-sex partners will be considered when
determining whether to exercise prosecutorial discretion in particular removal cases.11
These initiatives have been challenged by some Members of Congress and commentators on the
grounds that they are tantamount to “amnesty” for unauthorized aliens and are contrary to the
President’s constitutional responsibility to “take Care” that the laws be enforced.12 In particular,
some Members have suggested that DACA exceeds the President’s authority because “it was
issued after Congress specifically rejected legislation”—the Development, Relief, and Education
for Alien Minors (DREAM) Act—“embodying that policy.”13 In addition, several ICE agents and
the State of Mississippi have filed suit in federal district court for the Northern District of Texas
alleging that the DACA initiative violates certain statutory requirements and impinges upon
Congress’s legislative powers, among other things.14

(...continued)
contempt of Congress and violations of the Controlled Substances Act relating to the possession of marijuana. See
Letter from James M. Cole, Deputy Attorney General, to John Boehner, Speaker of the House, June 28, 2012;
Memorandum for Selected U.S. Attorneys from David W. Ogden, Deputy Attorney General, Investigations and
Prosecutions in States Authorizing the Medical Use of Marijuana, Oct. 19, 2009.
8 John Morton, Director, ICE, Civil Immigration Enforcement: Priorities for the Apprehension, Detention, and
Removal of Aliens, Mar. 2, 2011, at 1-2, available at http://www.ice.gov/doclib/news/releases/2011/
110302washingtondc.pdf (aliens who have been convicted of crimes, are at least 16 years of age and participate in
organized criminal gangs, are subject to outstanding criminal warrants, or “otherwise pose a serious risk to public
safety” constituting the highest priorities for removal).
9 John Morton, Director, ICE, Exercising Prosecutorial Discretion Consistent with the Civil Immigration Enforcement
Priorities of the Agency for the Apprehension, Detention, and Removal of Aliens, June 17, 2011, available at
http://www.ice.gov/doclib/secure-communities/pdf/prosecutorial-discretion-memo.pdf [hereinafter “2011 DHS
Guidance”].
10 Janet Napolitano, Secretary of Homeland Security, Exercising Prosecutorial Discretion with Respect to Individuals
Who Came to the United States as Children, June 15, 2012, at 1, available at http://www.dhs.gov/xlibrary/assets/s1-
exercising-prosecutorial-discretion-individuals-who-came-to-us-as-children.pdf.
11 Gary Mead, Executive Associate Director, ICE, et al., Applicability of Prosecutorial Discretion Memoranda to
Certain Family Relationships, Oct. 5, 2012, reproduced in 89 INTERPRETER RELEASES 1966-67 (Oct. 15, 2012).
12 See, e.g., “Does Administrative Amnesty Harm Our Efforts to Gain and Maintain Operational Control of the
Border?” Hearing Before the House Committee on Homeland Security, Subcommittee on Border and Maritime
Security, Oct. 4, 2011; “U.S. Immigration and Customs Enforcement: Priorities and the Rule of Law,” Hearing Before
the House Committee on the Judiciary, Oct. 12, 2011.
13 See, e.g., Testimony of Senator Michael S. Lee Before the House Committee on the Judiciary, “The Obama
Administration’s Abuse of Power,” Sept. 12, 2012, at 5, available at http://judiciary.house.gov/hearings/
Hearings%202012/Lee%2009122012.pdf; The Obama Administration, the DREAM Act, and the Take Care Clause,
supra note 3, at 5 (noting that the DREAM Act, “in one form or other, has been before Congress since 2001”).
14 See Crane, Amended Complaint, supra note 3. Two earlier suits challenging DACA were dismissed because the
plaintiffs lacked standing. See Peterson v. President of the United States, No. 1:2012cv00257, Order Granting Motion
to Dismiss (D.N.H., Oct. 22, 2012); Dutkiewicz v. Napolitano, No. 8:2012cv01447, Order Granting Motion to Dismiss
(continued...)
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This report begins by discussing the sources of federal power to regulate immigration and,
particularly, the allocation of power between Congress and the President in this area. It next
addresses the constitutional and other foundations for the doctrine of prosecutorial discretion, as
well as the potential ways in which prosecutorial discretion may be exercised in the immigration
context. It concludes by addressing potential constitutional, statutory, and administrative
constraints upon the exercise of prosecutorial discretion. The report does not address other
aspects of discretion in immigration law, such as the discretion exercised by immigration officers
in granting benefits (e.g., asylum), or by immigration judges in non-enforcement contexts (e.g.,
cancellation of removal).15
Federal Power to Regulate Immigration
The Constitution does not directly address the sources of federal power to regulate which non-
U.S. nationals (aliens) may enter and remain in the United States, or to establish the conditions of
their continued presence within the country. However, several of the enumerated powers of the
federal government have been construed as authorizing such regulation. The powers to establish a
uniform rule of naturalization and regulate commerce are arguably the most commonly cited
provisions, particularly in recent years.16 Various authorities related to foreign affairs have also
been routinely cited as providing support for particular enactments and activities in the field of
immigration.17 In addition, in some cases, the Supreme Court has suggested that federal

(...continued)
(M.D. Fla., Nov. 9, 2012).
15 See, e.g., Restrepo v. Holder, 676 F.3d 10 (1st Cir. 2012) (cancellation of removal pursuant to 8 U.S.C. § 1229b(a) is
solely within the Attorney General’s discretion absent a colorable constitutional claim or a question of law); Bo
Cooper, General Counsel, INS, INS Exercise of Prosecutorial Discretion, July 11, 2000, at 4, available at
http://iwp.legalmomentum.org/reference/additional-materials/immigration/enforcement-detention-and-criminal-justice/
government-documents/Bo-Cooper-memo%20pros%20discretion7.11.2000.pdf/view. (“The doctrine of prosecutorial
discretion applies to enforcement decisions, not benefit decisions. For example, a decision to charge, or not to charge,
an alien with a ground of deportability is clearly a prosecutorial enforcement decision. By contrast, the grant of an
immigration benefit, such as naturalization or adjustment of status, is a benefit decision that is not a subject for
prosecutorial discretion.”).
16 See, e.g., Nat’l Fed’n of Indep. Bus. v. Sebelius,—U.S.—, 132 S. Ct. 2566, 2600 (2012) (describing regulation of
immigration as among Congress’s powers under the Commerce Clause); Arizona v. United States,—U.S.—132 S. Ct.
2492, 2498 (2012) (authority to regulate immigration resting, in part, on the power to establish a uniform rule of
naturalization); Henderson v. Mayor of New York, 92 U.S. 259 (1876) (striking down New York and Louisiana laws
that required shipmasters to pay fees or post bonds to indemnify states if immigrants ended up on public assistance on
the grounds that the laws interfered with Congress’s power to regulate interstate commerce); Chy Lung v. Freeman, 92
U.S. 275 (1875) (striking down a California law regulating the entry of “lewd and debauched women” on the grounds
that it interfered with Congress’s power to regulate the admission of noncitizens); The Passenger Cases, 48 U.S. 283
(1849) (striking down New York and Massachusetts laws that levied fees on arriving immigrant passengers, in part, on
the grounds that such fees constituted unconstitutional regulations of foreign commerce).
17 See, e.g., The Chinese Exclusion Case, 130 U.S. 581, 604 (1889) (listing the powers to “declare war, make treaties,
suppress insurrection, repel invasion, regulate foreign commerce, secure republican governments to the States, and
admit subjects of other nations to citizenship” as authorizing Congress to enact legislation excluding Chinese laborers);
Fong Yue Ting v. United States, 149 U.S. 698, 705-09 (1893) (relying on the same sources to affirm Congress’s power
to deport noncitizens). See also Arizona, 132 S. Ct. at 2514 (Scalia, J., dissenting) (citing the Migration or Importation
Clause as a source of federal power over immigration). This clause, which pertains directly to slavery, can be seen as
addressing federal power to control the entry of certain persons into the United States.
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regulation of immigration is grounded in the federal government’s “inherent power as a sovereign
to control and conduct foreign relations.”18
Many, although not all, of these powers belong exclusively to Congress,19 and courts and
commentators have sometimes used language which implies that Congress is preeminent in the
field of immigration. For example, it has frequently been said that Congress has “plenary power”
over immigration,20 and that “over no conceivable subject is the legislative power of Congress
more complete than it is over” immigration.21 In some cases, courts have even suggested that the
executive branch’s authority over immigration arises from a delegation of congressional power, as
is the case with other Article I powers, although Article I does not give Congress clear supremacy
over immigration, as previously noted.22 In Sale v. Haitian Centers Council, Inc., for example, the
Supreme Court rejected a challenge which alleged that the executive branch’s procedures for
screening Haitian migrants at sea, without allowing them to disembark in the United States, did
not comply with statutory and treaty-based protections that enable aliens to apply for refugee
status and avoid repatriation.23 The Court did so, in part, on the grounds that “[t]he laws that the
Coast Guard is engaged in enforcing when it takes to the seas under orders to prevent aliens from
illegally crossing our borders are laws whose administration has been assigned to the Attorney
General by Congress.”24 Similarly, in other cases, the Court has described Congress’s power to
exclude aliens from the United States, or prescribe the terms and conditions upon which they may
enter, as being “enforced exclusively through executive officers,”25 or opined that executive
branch officials “exercise[] delegated legislative power” in taking specific actions.26

18 Arizona, 132 S. Ct. at 2498; Nishimara Ekiu v. United States, 142 U.S. 651, 659 (1892) (“It is an accepted maxim of
international law, that every sovereign nation has the power, as inherent in sovereignty, and essential to self-
preservation, to forbid the entrance of foreigners within its dominions, or to admit them only in such cases and upon
such conditions as it may see fit to prescribe.”).
19 In particular, the Constitution grants the treaty power to the President. See U.S. Const., art. II, §2 (“[The President]
shall have [the] Power, by and with the Advice and Consent of the Senate to make Treaties ...”).
20 See, e.g., Sale v. Haitian Centers Council, Inc., 509 U.S. 155, 201 (1993) (“Congress ... has plenary power over
immigration matters.”); INS v. Chadha, 462 U.S. 919, 940-41 (1983) (“The plenary authority of Congress over aliens
under Art. I, §8, cl. 4, is not open to question.”); Boutilier v. INS, 387 U.S. 118, 123 (1967) (“The Court without
exception has sustained Congress’ ‘plenary power to make rules for the admission of aliens.’”).
21 Oceanic Navigation Co. v. Stranahan, 214 U.S. 320, 339 (1909). This passage has been quoted in numerous other
cases. See, e.g., Reno v. Flores, 507 U.S. 292, 305 (1993); Fiallo v. Bell, 430 U.S. 787, 792 (1977); Kleindienst v.
Mandel, 408 U.S. 753, 766 (1972); Hana v. Gonzales, 503 F.3d 39, 43 (1st Cir. 2007).
22 Some commentators have suggested that the language in these cases may have been partially motivated by a desire to
enforce a more robust conception of the nondelegation doctrine. See, e.g., Adam B. Cox and Cristina M. Rodriguez,
The President and Immigration Law, 119 YALE L.J. 458, 474 n.46 (2009).
23 509 U.S. 155 (1993).
24 Id. at 201.
25 Lem Moon Sing v. United States, 158 U.S. 538, 547 (1895) (finding that the Act of 1894, which declared that the
decisions of the appropriate immigration or custom officers regarding the right of aliens to enter this country are
generally final, took away the court’s authority to review such decisions). See also Galvan v. Press, 347 U.S. 522, 531
(1954) (“In the enforcement of these policies, the Executive Branch of the Government must respect the procedural
safeguards of due process. But that the formulation of these policies is entrusted exclusively to Congress has become
about as firmly embedded in the legislative and judicial tissue of our body politic as any aspect of our government.”).
26 Mahler v. Eby, 264 U.S. 32, 43-45 (1924) (finding that certain deportation orders issued by the Secretary of Labor
were void because the orders did not indicate that the Secretary had made certain findings required by statute). See also
Kleindienst
, 408 U.S. at 769 (“[W]e think the Attorney General validly exercised the plenary power that Congress
delegated to the Executive by [certain provisions of the INA].”); Ng Fung Ho v. White, 259 U.S. 276, 280 (1922)
(“Congress has power to order at any time the deportation of aliens whose presence in the country it deems hurtful; and
may do so by appropriate executive proceedings.”); The Japanese Immigrant Case, 189 U.S. 86, 98 (1903) (“As to
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Few courts or commentators have, however, directly addressed the separation of powers between
Congress and the President in the field of immigration,27 and in some cases, the Court has also
suggested that the executive branch shares plenary power over immigration with Congress as one
of the “political branches.”28 While some such cases could potentially be construed as referring to
powers delegated to the executive branch by Congress, in other cases, the President has been
expressly said to have inherent authority over at least some immigration-related matters. For
example, in United States ex rel. Knauff v. Shaughnessy, the Court upheld the executive branch’s
decision to exclude a German “war bride,” in part, on the grounds that
The exclusion of aliens is a fundamental act of sovereignty. The right to do so stems not
alone from legislative power but is inherent in the executive power to control the foreign
affairs of the nation.... When Congress prescribes a procedure concerning the admissibility of
aliens, it is not dealing alone with a legislative power. It is implementing an inherent
executive power.29
Similarly, in Hampton v. Mow Sung Wong, the Court indicated that certain rules adopted by the
U.S. Civil Service Commission barring resident aliens from employment in the federal civil
service impermissibly deprived these aliens of due process of law, but that such rules would be
permissible if they “were expressly mandated by the Congress or the President.”30 Here, Congress

(...continued)
[aliens outside the United States], the decisions of executive or administrative officers, acting within powers expressly
conferred by Congress, are due process of law.”); Nishimura Ekiu, 142 U.S. at 659 (“The supervision of the admission
of aliens into the United States may be entrusted by Congress either to the Department of State, having the general
management of foreign relations, or to the Department of the Treasury, charged with the enforcement of the laws
regulating foreign commerce; and Congress has often passed acts forbidding the immigration of particular classes of
foreigners, and has committed the execution of these acts to the Secretary of the Treasury, to collectors of customs and
to inspectors acting under their authority.”).
27 Cf. The President and Immigration Law, supra note 22, at 510 (“[M]odern courts and commentators have largely
ignored the question of power allocation between the President and Congress.”); The Obama Administration, the
DREAM Act, and the Take Care Clause, supra note 3, at 3 (noting that the Constitution does not explicitly allocate
authority over immigration among the political branches). Only in the case of INS v. Chadha did the Supreme Court
confront a separation of powers question touching upon immigration. 462 U.S. 919 (1983). At issue in Chadha was the
permissibility of a statutory provision which authorized either house of Congress, by resolution, to invalidate the
executive branch’s determination to suspend deportation and adjust the status of aliens whose deportation would result
in “extreme hardship” to the alien or the alien’s family. The Court struck the statute down on separation of powers
grounds, finding that it violated the constitutional requirement that legislative acts be passed by both houses of
Congress and presented for the President’s approval. In reaching this conclusion, the Court noted both Congress’s
“plenary authority” over aliens, and that the “Attorney General acts in his presumptively Article II capacity when he
administers the [INA].” Id. at 940, 953 n.16. It is unclear, however, whether the reference to the Attorney General’s
“Article II capacity” means prosecutorial discretion under the Take Care Clause, or some other authority of the
executive.
28 See, e.g., United States v. Valenzuela-Bernal, 458 U.S. 858, 864 (1982) (“The power to regulate immigration—an
attribute of sovereignty essential to the preservation of any nation—has been entrusted by the Constitution to the
political branches of the Federal Government.”); Mathews v. Diaz, 426 U.S. 67, 81 (1976) (“[T]he relationship between
the U.S. and our alien visitors has been committed to the political branches of the federal government. Since decisions
in these matters may implicate our relations with foreign powers ... such decisions are frequently of a character more
appropriate to either the Legislature or the Executive branches than to the Judiciary.”); The Chinese Exclusion Case,
130 U.S. 581, 607-09 (1889) (rejecting the alien’s assertion that the federal government lacked the power to regulate
immigration, in part, because the “political department” of the United States had the responsibility for determining
“who shall compose [society’s] members”).
29 338 U.S. 537, 542 (1950).
30 426 U.S. 88, 103 (1976). Following the Court’s decision, President Ford issued an executive order reestablishing
these employment restrictions. Exec. Order No. 11, 935, 41 Fed. Reg. 37301 (Sept. 2, 1976). When challenged, this
order was found to be within the President’s authority. Vergara v. Hampton, 581 F.2d 1281 (7th Cir. 1978). However, in
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had delegated authority to the President to prescribe regulations for the admission of individuals
to the civil service. Accordingly, it is possible that when the Hampton Court referred to the
President’s power to limit alien eligibility for federal employment, it intended to refer only to the
power which had been conferred to him by Congress. On the other hand, the Court’s discussion of
the interests of the President that might be sufficient to justify the exclusion of noncitizens from
the civil service focused upon the President’s power to negotiate treaties, suggesting recognition
of some independent constitutional basis for executive branch activity in the field of
immigration.31
The possibility of independent executive branch authority over immigration is significant in that
any such authority could potentially help justify certain actions taken by the executive branch
(although actions taken in reliance on such authority could also potentially raise issues if they
were arguably within Congress’s purview).32 However, the executive branch’s authority to
exercise prosecutorial or enforcement discretion has traditionally been understood to arise from
the Constitution,33 as discussed below.
Courts have historically not required that the executive branch have specific statutory
authorization for particular exercises of prosecutorial discretion. Thus, immigration officials
would not necessarily be precluded from granting deferred action, or taking certain other actions
that could permit otherwise removable aliens to remain in the United States, just because federal
immigration statutes do not expressly authorize such actions.34 On the other hand, Section

(...continued)
so finding, the reviewing court emphasized the President’s statutory authority under 5 U.S.C. §3301(1), not any
inherent authority over immigration or aliens.
31 Hampton, 426 U.S. at 104 (“In this case the petitioners have identified several interests which the Congress or the
President might deem sufficient to justify the exclusion of noncitizens from the federal service. They argue, for
example, that the broad exclusion may facilitate the President’s negotiation of treaties with foreign powers by enabling
him to offer employment opportunities to citizens of a given foreign country in exchange for reciprocal concessions.”).
32 Any assertion of inherent, independent, or implied constitutional presidential authority in the field of immigration
may be evaluated under the rubric established by Justice Jackson’s concurring opinion in Youngstown Sheet & Tube
Co. v. Sawyer
, 343 U.S. 579 (1952). The Youngstown framework, which the Court has characterized as bringing
“together as much combination of analysis and common sense as there is in this area,” has generally been applied when
a President seeks to take action within an area generally considered to be within Congress’s purview. See, e.g., Dames
& Moore v. Regan, 453 U.S. 654, 661-62 (1981). Importantly, the scope of executive authority under the Jackson
analysis is judged in direct relation to congressional action in the field. When the President acts pursuant to an
authorization from Congress, his power is “at its maximum.” To the contrary, when the President seeks to take action
that conflicts with Congress’s expressed will, his power is at its “lowest ebb, for then he can rely only upon his own
constitutional powers minus any constitutional powers of Congress over the matter.” Where Congress is silent, “there is
a zone of twilight in which he and Congress may have concurrent authority, or in which its distribution is uncertain.”
Youngstown, 343 U.S. at 635-37. Any claimed constitutional authority justifying executive action in the field of
immigration would, therefore, likely be evaluated in relation to the policies established by Congress in the INA and
other pertinent statutes.
33 See, e.g., United States v. Armstrong, 517 U.S. 456, 464 (1996) (noting that the Attorney General and the United
States Attorneys have wide latitude in enforcing federal criminal law because “they are designated by statute as the
President’s delegates to help him discharge his constitutional duty to ‘take Care that the Laws be faithfully executed’”);
Heckler, 470 U.S. at 831 (“[W]e recognize that an agency’s refusal to institute proceedings shares to some extent the
characteristics of the decision of a prosecutor in the Executive Branch not to indict—a decision which has long been
regarded as the special province of the Executive Branch, inasmuch as it is the Executive who is charged by the
Constitution to ‘take Care that the Laws be faithfully executed.’”).
34 An argument could also potentially be made that Congress has impliedly delegated the authority to exercise certain
types of discretion to the executive branch since it has been aware of the practice, and could be said to have acquiesced.
See, e.g., Johns v. Dep’t of Justice, 653 F.2d 884, 890 (5th Cir. 1981) (“Deportation is not, however, the inevitable
consequence of unauthorized presence in the United States. The Attorney General is given discretion by express
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103(a)(3) of the INA authorizes the Secretary of Homeland Security to “perform such other acts
as he deems necessary for carrying out his authority under the provisions of this chapter,” and has
been construed by some as “commit[ting] enforcement of the INA to [the Secretary’s]
discretion.”35 The federal government recently noted its discretion under Section 103(a)(3) in
seeking dismissal of a lawsuit challenging the DACA initiative.36 The Secretary’s authority under
Section 103(a)(3) of the INA is, however, an authority granted to the executive branch by
Congress and, as such, is distinguishable from the President’s constitutional authority to “take
Care” that the laws be enforced. Congress could, for example, potentially limit the discretion
granted to the Secretary by Section 103(a)(3) of the INA, including by prohibiting particular
exercises of discretion. In contrast, Congress probably could not directly limit the President’s
authority under the Constitution to “take Care” that the laws be enforced.
The INA also grants the Secretary other types of discretion which are sometimes mentioned in
connection with exercises of prosecutorial or enforcement discretion, but do not themselves
involve determinations regarding when, whom, how, and even whether to prosecute apparent
violations of the law. In some cases, the INA expressly provides that certain determinations are
within the discretion of immigration officials, such as the determination to waive the bar upon
admissibility for alien spouses or children of U.S. citizens or lawful permanent residents (LPRs)
who have been present in the United States without authorization for more than 180 days.37 In
other cases, the INA does not expressly mention the discretion of executive branch officials, but
effectively affords them such discretion by leaving certain details of the statutory scheme to be
implemented by the executive branch. Thus, the INA affords the Secretary discretion to determine
which aliens are granted employment authorization by prohibiting the employment of
unauthorized aliens, and defining “unauthorized alien,” in part, as an alien who has not been
“authorized to be ... employed by the [Secretary].”38 Because it is conferred by Congress, this
discretion, like the Secretary’s discretion under Section 103(a)(3), could also be limited by
Congress.
Prosecutorial Discretion Generally
The judicial branch has traditionally accorded federal prosecutors “broad” latitude in making a
range of investigatory and prosecutorial determinations, including when, whom, and whether to

(...continued)
statutory provisions, in some situations, to ameliorate the rigidity of the deportation laws. In other instances, as the
result of implied authority, he exercises discretion nowhere granted expressly.”).
35 Texas v. United States, 106 F.3d 661, 667 (5th Cir. 1997) (rejecting allegations that the Attorney General had
breached his nondiscretionary duty under the INA to control immigration, in part, on the grounds that enforcement of
the INA is committed to the Attorney General’s discretion). See also Hotel & Rest. Employees Union Local 25 v.
Smith, 846 F.2d 1499, 1510 (D.C. Cir. 1988) (citing Section 103(a)(3) to support the proposition that the then-Attorney
General enjoyed “broad latitude in enforcing the immigration laws,” and that the decision to grant or withhold extended
voluntary departure “falls within this broad mandate”), aff’g, 563 F. Supp. 157 (D.D.C. 1983).
36 Crane v. Napolitano, No. 3:12-CV-3247-O, Defendants’ Motion to Dismiss and Memorandum in Support (filed N.D.
Tex., Nov. 13, 2012). The INS had previously expressed the view that Section 242(g) of the INA meant that it had
discretion not to pursue removal against an alien because such decisions are not judicially reviewable. See INS Exercise
of Prosecutorial Discretion, supra note 15, at 9. However, DHS does not appear to rely upon this argument at present.
37 INA §212(a)(9)(B); 8 U.S.C. §1182(a)(9)(B). Any such waivers may only be granted where certain conditions are
met (e.g., the refusal of admission to the alien would result in “extreme hardship” to his or her citizen or LPR relatives).
38 INA §274a(h)(3); 8 U.S.C. §1324a(h)(3).
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prosecute particular violations of federal law. 39 This doctrine of “prosecutorial discretion” has a
long historical pedigree—the early roots of which can be traced at least to a Sixteenth Century
English common law procedural mechanism known as the nolle prosequi.40 In the early English
legal system, criminal prosecutions were generally initiated by private individuals rather than
public prosecutors. The nolle prosequi, however, allowed the government, generally at the
direction of the Crown, to intervene in and terminate a privately initiated criminal action it
viewed as “frivolous or in contravention of royal interests.”41 The discretionary device was later
adopted into American common law and has been used by prosecutors to terminate criminal
prosecutions that are determined to be unwarranted or which the prosecuting authority chooses
not to pursue.42
Notwithstanding this historical background, the modern doctrine of prosecutorial discretion
derives more from our constitutional structure than English common law. However, the exact
justification for the doctrine does not appear to have been explicitly established. Generally, courts
have characterized prosecutorial discretion as a function of some mixture of the separation of
powers, the Take Care Clause,43 or the duties of a prosecutor as an appointee of the President.44
Moreover, both federal and state courts have ruled that the exercise of prosecutorial discretion is
an executive function necessary to the proper administration of justice. Given these precedents,
prosecutorial discretion may be appropriately characterized as a constitutionally based doctrine.
Regardless of its precise textual source, courts generally will neither review nor question
discretionary prosecutorial decisions, nor “coerce” the executive branch to initiate a particular

39 See, e.g., Wayte v. United States, 470 U.S. 598, 607 (1985) (“In our criminal justice system, the Government retains
‘broad discretion’ as to whom to prosecute.”) (citing United States v. Goodwin, 457 U.S. 368, 380 (1982)); United
States v. Nixon, 418 U.S. 683, 693 (1974) (“[T]he Executive Branch has exclusive authority and absolute discretion to
decide whether to prosecute a case…”) (citing the Confiscation Cases, 74 U.S. 454 (1869)).
40 See, e.g., Rebecca Krauss, The Theory of Prosecutorial Discretion in Federal Law: Origins and Development, 6
SETON HALL CIR. REV. 1, 19-26 (2009) (describing the English use of the nolle prosequi and its “absorb[tion]” by
American law).
41 Id. at 20.
42 See, e.g., Confiscation Cases, 74 U.S. 454 (1869); Newman v. United States, 382 F.2d 479, 480 (D.C. Cir. 1967)
(“Most recently, the issue of the United States Attorney’s ‘discretionary control of criminal prosecutions has arisen in
connection with the filing of a nolle prosequi, and the Courts have regularly refused to interfere with these voluntary
dismissals of prosecution.’”) (citing Louis B. Schwartz, Federal Criminal Jurisdiction and Prosecutors’ Discretion, 13
LAW & CONTEMP. PROB. 64, 83 (1948)). Today, judicial approval is generally required before a prosecutor may dismiss
an ongoing prosecution. See FED. R. CRIM. P. 48(a) (“The government may, with leave of court, dismiss an indictment,
information, or complaint.”).
43 U.S. Const. Art. II, §3 (“[H]e shall take Care that the Laws be faithfully executed.... ”).
44 See, e.g., Armstrong, 517 U.S. at 464 (“They have this latitude because they are designated by statute as the
President’s delegates to help him discharge his constitutional responsibility to ‘take Care that the Laws be faithfully
executed.’”); Confiscation Cases, 74 U.S. at 458 (“Appointed, as the Attorney General is, in pursuance of an act of
Congress, to prosecute and conduct such suits, argument would seem to be unnecessary to prove his authority to
dispose of these cases in the manner proposed.... ”); Ponzi v. Fessenden, 258 U.S. 254, 262 (1922) (“The Attorney
General is the head of the Department of Justice. He is the hand of the President in taking care that the laws of the
United States in protection of the interests of the United States in legal proceedings and in the prosecution of offences
be faithfully executed.”); United States v. Cox, 342 F.2d 167, 171 (5th Cir. 1965) (“The Attorney General is the hand of
the President in taking care that the laws of the United States in legal proceedings and in the prosecution of offenses, be
faithfully executed. Although as a member of the bar, the attorney for the United States is an officer of the court, he is
nevertheless an executive official of the Government, and it is as an officer of the executive department that he
exercises discretion as to whether or not there shall be a prosecution in a particular case. It follows, as an incident of the
constitutional separation of powers, that the courts are not to interfere with the free exercise of the discretionary powers
of the attorneys of the United States in their control over criminal prosecutions.”) (internal citations omitted)).
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prosecution. In acknowledging the discretion possessed by enforcement officials, courts have
recognized that the “decision to prosecute is particularly ill-suited to judicial review,” as it
involves the consideration of factors—such as the strength of evidence, deterrence value, and
existing enforcement priorities—“not readily susceptible to the kind of analysis the courts are
competent to undertake.”45 Moreover, the executive branch has asserted that “because the
essential core of the President’s constitutional responsibility is the duty to enforce the laws, the
Executive Branch has exclusive authority to initiate and prosecute actions to enforce the laws
adopted by Congress.”46
An agency decision to initiate an enforcement action in the administrative context “shares to
some extent the characteristics of the decision of a prosecutor in the executive branch” to initiate
a prosecution in the criminal context.47 Thus, just as courts are hesitant to question a prosecutor’s
decisions with respect to whether to bring a criminal prosecution, so too are courts cautious in
reviewing an agency’s decision not to bring an enforcement action. In the seminal case of Heckler
v. Cheney
, the Supreme Court held that “an agency’s decision not to prosecute or enforce,
whether through civil or criminal process, is a decision generally committed to an agency’s
absolute discretion.”48 The Court noted that agency enforcement decisions, like prosecution
decisions, involve a “complicated balancing” of agency interests and resources—a balancing that
the agency is “better equipped” to evaluate than the courts.49 The Heckler opinion proceeded to
establish the standard for the reviewability of agency non-enforcement decisions, holding that an
“agency’s decision not to take enforcement action should be presumed immune from judicial
review.”50 However, the Court indicated that, in certain cases, that presumption may be overcome
“where the substantive statute has provided guidelines for the agency to follow in exercising its
enforcement powers,” 51 as is discussed below.

45 Wayte, 470 U.S. at 607. However, the U.S. Court of Appeals for the District of Columbia Circuit has observed that
“the decisions of this court have never allowed the phrase ‘prosecutorial discretion’ to be treated as a magical
incantation which automatically provides a shield for arbitrariness.” Med. Comm. for Human Rights v. SEC, 432 F.2d
659, 673 (D.C. Cir. 1970).
46 See Prosecution for Contempt of Congress of an Executive Branch Official Who Has Asserted a Claim of Executive
Privilege
, 8 OP. OFF. LEGAL COUNSEL 101, 114 (1984) (emphasis added). This traditional conception may, however,
have been qualified in some respects following the Supreme Court’s decision in Morrison v. Olson, in which the Court
upheld a congressional delegation of prosecutorial power to an “independent counsel” under the Ethics in Government
Act. In sustaining the validity of the statute’s appointment and removal conditions, the Court suggested that although
the independent counsel’s prosecutorial powers—including the “no small amount of discretion and judgment [exercised
by the counsel] in deciding how to carry out his or her duties under the Act”—were executive in that they had
“typically” been performed by executive branch officials, the court did not consider such an exercise of prosecutorial
power to be “so central to the functioning of the Executive Branch” as to require Presidential control over the
independent counsel. 487 U.S. 654 (1988). While the ultimate reach of Morrison may be narrow in that the independent
counsel was granted only limited jurisdiction and was still subject to the supervision of the Attorney General, it does
appear that Congress may vest certain prosecutorial powers, including the exercise of prosecutorial discretion, in an
executive branch official who is independent of traditional presidential controls. But see Nixon, 418 U.S. at 693 (“[T]he
Executive Branch has exclusive authority and absolute discretion to decide whether to prosecute a case.... ”).
47 Heckler, 470 U.S. at 832. The Court also expressed concern that judicial review of agencies’ exercise of
prosecutorial discretion could impose “systemic costs” by delaying criminal proceedings, chilling law enforcement, and
undermining prosecutorial effectiveness. Id. at 833.
48 Id. at 831. Accordingly, such decisions are generally precluded from judicial review under the Administrative
Procedure Act (APA). 5 U.S.C. §701 (establishing an exception to the APA’s presumption of reviewability where
“agency action is committed to agency discretion by law”).
49 Heckler, 470 U.S. at 831.
50 Id. at 832.
51 Id. at 833.
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Prosecutorial Discretion in the Immigration Context
In Reno v. American-Arab Anti-Discrimination Committee, a majority of the Supreme Court
found that the various prudential concerns that prompt deference to the executive branch’s
determinations as to whether to prosecute criminal offenses are “greatly magnified in the
deportation context,”52 which entails civil (rather than criminal) proceedings.53 While the reasons
cited by the Court for greater deference to exercises of prosecutorial discretion in the immigration
context than in other contexts reflect the facts of the case, which arose when certain removable
aliens challenged the government’s decision not to exercise prosecutorial discretion in their
favor,54 the Court’s language is broad and arguably can be construed to encompass decisions to
favorably exercise such discretion. More recently, in its decision in Arizona v. United States, a
majority of the Court arguably similarly affirmed the authority of the executive branch not to seek
the removal of certain aliens, noting that “[a] principal feature of the removal system is the broad
discretion entrusted to immigration officials,” and that “[r]eturning an alien to his own country
may be deemed inappropriate even where he has committed a removable offense or fails to meet
the criteria for admission.”55 According to the majority, such exercises of prosecutorial discretion
may reflect “immediate human concerns” and the “equities of … individual case[s],” such as
whether the alien has children born in the United States or ties to the community, as well as
“policy choices that bear on … international relations.”56
Going beyond such general affirmations of the executive branch’s prosecutorial discretion in the
immigration context, other cases have specifically noted that certain decisions are within the
prosecutorial discretion of INS and, later, the immigration components of DHS. These decisions
include
• whether to parole an alien into the United States;57

52 525 U.S. 471, 490 (1999). See also Shaughnessy, 338 U.S. at 543 (noting that immigration is a “field where
flexibility and the adaptation of the congressional policy to infinitely variable conditions constitute the essence of the
program”).
53 See, e.g., Padilla v. Kentucky,—U.S.—, 130 S. Ct. 1473, 1481 (2010) (“We have long recognized that deportation is
a particularly severe ‘penalty,’ but it is not, in a strict sense, a criminal sanction.”) (internal citations omitted); INS v.
Lopez-Mendoza, 468 U.S. 1032, 1038-39 (1984) (“A deportation proceeding is a purely civil action to determine
eligibility to remain in this country, not to punish an unlawful entry.... The purpose of deportation is not to punish past
transgressions but rather to put an end to a continuing violation of the immigration laws.”).
54 Specifically, the Court noted that any delays in criminal proceedings caused by judicial review of exercises of
prosecutorial discretion would “merely … postpone the criminal’s receipt of his just desserts,” while delays in removal
proceedings would “permit and prolong a continuing violation of United States law,” and could potentially permit the
alien to acquire a basis for changing his or her status. Reno, 525 U.S. at 490. The Court further noted that immigration
proceedings are unique in that they can implicate foreign policy objectives and foreign-intelligence techniques that are
generally not implicated in criminal proceedings. Id. at 491. It also found that the interest in avoiding selective or
otherwise improper prosecution in immigration proceedings, discussed below, is “less compelling” than in criminal
proceedings because deportation is not a punishment and may be “necessary to bring to an end an ongoing violation of
United States law.” Id. (emphasis in original).
55 Arizona,132 S. Ct. at 2498. Justice Scalia’s dissenting opinion, in contrast, specifically cited Secretary Napolitano’s
memorandum regarding the exercise of prosecutorial discretion with respect to certain aliens who came to the United
States as children when asserting that “there is no reason why the Federal Executive’s need to allocate its scarce
enforcement resources should disable Arizona from devoting its resources to illegal immigration in Arizona that in its
view the Federal Executive has given short shrift.” Id. at 2520 (Scalia, J., dissenting) (emphasis in original)).
56 Arizona, 132 S. Ct. at 2499.
57 Assa’ad v. U.S. Attorney General, 332 F.3d 1321, 1339 (11th Cir. 2003); Matter of Artigas, 23 I. & N. Dec. 99 (BIA
(continued...)
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• whether to commence removal proceedings and what charges to lodge against the
respondent;58
• whether to pursue formal removal proceedings;59
• whether to cancel a Notice to Appear or other charging document before
jurisdiction vests with an immigration judge;60
• whether to grant deferred action or extended voluntary departure;61
• whether to appeal an immigration judge’s decision or order, and whether to file a
motion to reopen;62
• whether to invoke an automatic stay during the pendency of an appeal;63 and
• whether to impose a fine for particular offenses.64
As used here, deferred action is “generally an act of prosecutorial discretion to suspend [taking
action] against a particular individual or group of individuals for a specific timeframe; it cannot
resolve an individual’s underlying immigration status.”65 It is generally granted on a case-by-case
basis, although the executive branch has sometimes provided that individuals who share certain
characteristics (e.g., advanced or young age) are to be given particular consideration for deferred
action.66 In contrast, extended voluntary departure—sometimes also referred to as deferred

(...continued)
2001) (Filppu, J., dissenting). DHS grants an alien parole when it permits the alien to physically enter the United States
and to remain as a matter of sufferance only, and without having made an “entry,” for “urgent humanitarian reasons or
significant public benefit.” INA §212(d)(5)(A); 8 U.S.C. §1182(d)(5)(A).
58 Hanggi v. Holder, 563 F.3d 378, 383 (8th Cir. 2009); Rodrigues v. Attorney General of the United States, 414 Fed.
App’x 484, 488 (3d Cir. 2011); Matter of Avetisyan, 25 I. & N. Dec. 688 (BIA 2012); Matter of Bahta, 22 I. & N. Dec.
1381 (BIA 2000); Matter of Singh, 21 I. & N. Dec. 427 (BIA 1996); Matter of Ruis, 18 I. & N. Dec. 320 (BIA 1982);
Matter of Roussis, 18 I. & N. Dec. 256 (BIA 1982); Matter of Lennon, 15 I. & N. Dec. 9 (BIA 1974).
59 Matter of Lujan-Quintana, 25 I. & N. Dec. 53 (BIA 2009). But see Flores-Ledezma v. Gonzales, 415 F.3d 375, 382
(5th Cir. 2005) (“Although we decline at this juncture to equate the Attorney General’s discretion to choose which
proceeding a non-LPR will receive with prosecutorial discretion, it is fully convincing that the Government has
highlighted a rational basis for the Attorney General’s exercise of such discretion.”). Section 240 of the INA provides
for formal removal proceedings. However, “expedited removal,” without formal proceedings, is also possible in the
case of certain aliens seeking admission to the United States. INA §235(b); 8 U.S.C. §1225(b).
60 Matter of G-N-C, 22 I. & N. Dec. 281 (BIA 1998). See also Akhtar v. Gonzales, 450 F.3d 587, 591 (5th Cir. 2006)
(whether to terminate removal proceedings to allow the alien to apply for immigration benefits that may potentially be
available).
61 Hotel & Rest. Employees Union Local 25, 846 F.2d at 1510-11; Barahona-Gomez v. Reno, 236 F.3d 1115, 1119 n.3
(9th Cir. 2001); Johnson v. INS, 962 F.2d 574, 579 (7th Cir. 1992); Carmona Martinez v. Ashcroft, 118 Fed. App’x 238,
239 (9th Cir. 2004); Matter of Yauri, 25 I. & N. Dec. 103 (BIA 2009); Matter of Singh, 21 I. & N. Dec. 427 (BIA 1996);
Matter of Luviano-Rodriguez, 21 I. & N. Dec. 235 (BIA 1996); Matter of Quintero, 18 I. & N. Dec. 348 (BIA 1982).
62 Matter of Avetisyan, 25 I. & N. Dec. 688 (BIA 2012); Matter of York, 22 I. & N. Dec. 660 (BIA 1999); Matter of
Joseph
, 22 I. & N. Dec. 660 (BIA 1990).
63 Matter of Joseph, 22 I. & N. Dec. 660 (BIA 1999).
64 Matter of M/V Saru Meru, 20 I. & N. Dec. 592 (BIA 1992); Matter of M/V Solemn Judge, 18 I. & N. Dec. 186 (BIA
1982).
65 Shoba Sivaprasad Wadhia, The Role of Prosecutorial Discretion in Immigration Law, 9 CONN. PUB. INT. L.J. 243,
263 (2010) (quoting a 2009 DHS press release on relief for widows of U.S. citizens). Individual aliens may request that
they be granted deferred action (formerly known as non-priority status), or immigration officials may decide, sua
sponte
, to defer action.
66 See, e.g., Exercising Prosecutorial Discretion with Respect to Individuals Who Came to the United States as
(continued...)
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departure or deferred enforced departure—generally involves “blanket relief” from removal to
particular countries.67
Many of the actions that judicial and administrative tribunals have noted are within the
prosecutorial discretion of immigration officers have also been mentioned in INS and, later, DHS,
guidance regarding the exercise of prosecutorial discretion. Memoranda or other documents
providing such guidance have been issued intermittently since at least 1976, and have suggested
that officers may generally exercise discretion in
• deciding whether to issue or cancel a notice of detainer;
• deciding whether to issue, reissue, serve, file, or cancel a Notice to Appear;
• focusing administrative resources on particular violations or conduct;
• deciding whom to stop, question, or arrest for a violation;
• deciding whether to detain aliens who are not subject to “mandatory detention”
pending removal, or whether to release them on bond, supervision, personal
recognizance, or other conditions;
• seeking expedited removal or removal by means other than formal proceedings in
immigration court;
• settling or dismissing a proceeding;
• granting deferred action or parole;
• staying a final order of removal;
• agreeing to voluntary departure, the withdrawal of an application for admission,
or other action in lieu of a formal order of removal;
• pursuing an appeal;
• executing a removal order; and
• responding to or joining in a motion to reopen removal proceedings, or joining in
a motion to grant relief or a benefit.68
Often, this executive branch guidance has highlighted resource constraints,69 as well as
humanitarian considerations,70 that may warrant a favorable exercise of prosecutorial discretion,

(...continued)
Children, supra note 10; John Morton, Director, ICE, Prosecutorial Discretion: Certain Victims, Witnesses, and
Plaintiffs, June 17, 2011, available at http://www.ice.gov/doclib/secure-communities/pdf/domestic-violence.pdf;
Prosecutorial and Custody Detention, supra note 2.
67 See, e.g., Extended Voluntary Departure, supra note 5, at 155-59.
68 See, e.g., 2011 DHS Guidance, supra note 9, at 2-3; Civil Immigration Enforcement, supra note 8, at 3; Prosecutorial
Discretion: Certain Victims, Witnesses, and Plaintiffs, supra note 66, at 2; William J. Howard, Principal Legal Advisor,
ICE, Prosecutorial Discretion, Oct. 24, 2005, at 2, available at http://iwp.legalmomentum.org/reference/additional-
materials/immigration/enforcement-detention-and-criminal-justice/government-documents/22092975-ICE-Guidance-
Memo-Prosecutorial-Discretion-William-J-Howard-10-24-05.pdf/view; 2002 INS Guidance, supra note 2.
69 See, e.g., Applicability of Prosecutorial Discretion Memoranda to Certain Family Relationships, supra note 11 (“This
and other memoranda related to prosecutorial discretion are designed to ensure that agency resources are focused on
our enforcement priorities, including individuals who pose a threat to public safety, are recent border crossers, or
repeatedly violate our immigration laws.”); Civil Immigration Enforcement, supra note 8, at 1 (“ICE ... only has
(continued...)
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although such guidance has generally also indicated that determinations as to whether to exercise
discretion in particular cases are to be based on the “totality of the circumstances”71 and whether
a “substantial federal interest” is present.72 The guidance may also suggest when in the process
such discretion is to be exercised (generally as early in the process as possible, so as to avoid
wasting government resources),73 as well as which officers may exercise particular forms of
discretion.74 While personnel are generally instructed that they should “always consider
prosecutorial discretion on a case-by-case basis,”75 classes of individuals warranting
consideration for favorable—or unfavorable—exercises of discretion have sometimes been
identified (e.g., minors and elderly individuals, known gang members).76
Potential Limits on the Exercise of Discretion
While prosecutorial discretion is broad, it is not “unfettered,”77 and particular exercises of
discretion could potentially be checked by the Constitution, statute, or agency directives.78 In
practice, however, persons who are neither aliens nor otherwise subject to the requirements of the
INA could lack standing to challenge alleged abuses of prosecutorial discretion in the
immigration context. Standing is generally limited to persons who allege a “personal injury fairly
traceable to the defendant’s allegedly unlawful conduct and likely to be redressed by the
requested relief.”79 Those whose sole injury is the government’s alleged failure to follow the law

(...continued)
resources to remove approximately 400,000 aliens per year, less than 4 percent of the estimated illegal alien population
of the United States.”); Prosecutorial Discretion, supra note 68 (noting demands created by the establishment of DHS
and the increasing number of immigration cases being litigated in federal courts).
70 See, e.g., 2011 DHS Guidance, supra note 9, at 4 (noting that factors to consider include the alien’s length of
presence in the United States; the circumstances of the alien’s arrival in the United States; the alien’s pursuit of
education in the United States; the alien’s ties and contributions to the community; whether the alien or the alien’s
spouse is pregnant or nursing, or suffers from a severe mental or physical illness; and conditions in the alien’s home
country); Prosecutorial Discretion, supra note 68 (aliens who are immediate relatives of members of the U.S. military;
aliens who have citizen children with serious medical conditions or disabilities; aliens who are undergoing treatment
for a potentially life-threatening illness).
71 See, e.g., 2011 DHS Guidance, supra note 9, at 2.
72 See, e.g., 2002 INS Guidance, supra note 2, at 4.
73 See, e.g., id. at 6.
74 See, e.g., 2011 DHS Guidance, supra note 9, at 3. One particular area where such policies have shifted over time is
whether immigration attorneys have the authority to cancel Notices to Appear issued by immigration officers.
75 2011 DHS Guidance, supra note 9, at 4. See also Civil Immigration Enforcement, supra note 8, at 4.
76 2011 DHS Guidance, supra note 9, at 5; Prosecutorial and Custody Detention, supra note 2; 2002 INS Guidance,
supra note 2, at 11.
77 United States v. Batchelder, 442 U.S. 114, 125 (1979).
78 See, e.g., Nader v. Saxbe, 497 F.2d 676, 679 (D.C. Cir. 1974) (“It would seem to follow that the exercise of
prosecutorial discretion, like the exercise of Executive discretion generally, is subject to statutory and constitutional
limits enforceable through judicial review.”).
79 DaimlerChrysler Corp. v. Cuno, 547 U.S. 332, 342 (2006) (quoting Allen v. Wright, 468 U.S. 737, 751 (1984)). The
requirements as to injury, causation, and redressibility refer to Article III standing. However, plaintiffs challenging
certain actions in the immigration context have also been found to lack prudential standing to enforce the INA. See,
e.g.
, Fed’n for Am. Immigration Reform v. Reno, 93 F.3d 897, 900 (D.C. Cir. 1996) (plaintiffs were not within the
zone of interests protected by the INA for purposes of their claim that a “rush of immigrants adversely affects the
welfare of the Federation’s members by generating unemployment and wage reductions”).
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will generally be found to lack standing because this injury is not personal and particularized.80
Even government officers and employees, who have taken an oath to uphold the law, will
generally be found to lack standing so long as their only asserted injury is being forced to violate
their oaths by implementing an allegedly unlawful policy or practice.81 Instead, they must allege
some separate and concrete adverse consequence that would flow from violating their oath, and
the possibility of being disciplined for obeying allegedly unlawful orders generally would not
suffice since courts have viewed such injury as “entirely speculative.”82 Courts have imposed
these limitations, in part, on the grounds that recognizing standing in such cases would allow
persons to sue “merely ... to ensure [that federal] law conforms to [their] opinion of what federal
law requires,” and such personal opinions could change at any time.83
In addition, even where standing to challenge particular exercises of prosecutorial discretion
exists, plaintiffs could potentially have difficulty obtaining relief given that actions by Congress
or the President in the immigration context are generally subject to a “narrow standard of
review,”84 particularly in cases where such decisions implicate foreign affairs or national security.
For example, in its recent decision in Arizona v. United States, a majority of the Supreme Court
noted that “[s]ome discretionary decisions involve policy choices that bear on this Nation’s
international relations” when explaining the basis for the “broad discretion” immigration officers
have in determining whether to remove unauthorized aliens.85 The Court has similarly
emphasized the potential “diplomatic repercussions” of certain decisions made by immigration
officers (e.g., determining whether to grant withholding of removal or an alien’s petition to
reopen deportation proceedings).86 Moreover, in some cases, courts have found that challenges to

80 See, e.g., Lance v. Coffman, 549 U.S. 437, 439 (2007) (“A plaintiff raising only a generally available grievance
about government—claiming only harm to his and every citizen’s interest in [the] proper application of the Constitution
and laws, and seeking relief that no more directly [or] tangibly benefits him than it does the public at large—does not
state an Article III case or controversy.”) (internal quotations omitted)); Lujan v. Defenders of Wildlife, 504 U.S. 555,
562 (1992) (“[W]hen the plaintiff is not himself the object of the government action or inaction he challenges, standing
is not precluded, but is ordinarily ‘substantially more difficult’ to establish.”). Individual Members of Congress also
generally lack standing to challenge presidential actions. In Raines v. Byrd, the Supreme Court held that in order to
obtain standing an individual Member must assert either a personal injury, like the loss of his congressional seat, or an
institutional injury that amounts to vote nullification, which requires that no other legislative remedy exists to redress
the alleged injury. See 521 U.S. 811 (1997).
81 See, e.g., Donelon v. La. Div. of Admin. Law ex rel. Wise, 522 F.3d 564 (5th Cir. 2008) (Louisiana Commissioner of
Insurance lacked standing to challenge the constitutionality of a state law which he alleged violated the Constitution);
Finch v. Miss. State Med. Ass’n, Inc., 585 F.2d 765, 773-75 (5th Cir. 1978) (governor of Mississippi lacked standing to
challenge a state law whose enforcement, he believed, would cause him to violate his oath to uphold the federal and
state constitutions).
82 Drake v. Obama, 664 F.3d 774, 780 (9th Cir. 2011) (“The notion that [the plaintiff] will be disciplined by the military
for obeying President Obama’s orders is entirely speculative. He might be disciplined for disobeying those orders, but
he has an ‘available course of action which subjects [him] to no concrete adverse consequences’—he can obey the
orders of the Commander-in-Chief.”) (emphasis in original)). The plaintiffs in Drake included members of the military
who alleged that they would violate their oaths if they obeyed the orders of President Obama because President Obama
is not a natural born citizen and, thus, does not meet the constitutional qualifications to be commander-in-chief.
83 Donelon, 552 F.3d at 568 (emphasis in original).
84 See, e.g., Miller v. Albright, 523 U.S. 420, 434 n.11 (1998) (plurality opinion); Fiallo, 430 U.S. at 796; Mathews,
426 U.S. at 82.
85 See, e.g., Arizona, 132 S. Ct. at 2499.
86 Negusie v. Holder, 555 U.S. 511, 517 (2009) (“The Attorney General’s decision to bar an alien who has participated
in persecution ‘may affect our relations with [the alien’s native] country or its neighbors. The judiciary is not well
positioned to shoulder primary responsibility for assessing the likelihood and importance of such diplomatic
repercussions.”); INS v. Abudu, 485 U.S. 94, 110 (1988) (“Although all adjudications by administrative agencies are to
some degree judicial and to some degree political ... INS officials must exercise especially sensitive political functions
(continued...)
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the alleged nonenforcement of immigration laws involve nonjusticiable political questions
because they fundamentally entail disagreements about the proper extent of immigration
enforcement.87
Constitution
The U.S. Constitution can be seen as imposing two potential limitations upon the executive
branch’s exercise of prosecutorial discretion, one in cases where the Executive decides to enforce
the law against particular individuals because of their race, religion, exercise of a constitutional
right, or other impermissible factors; and the other in cases where the Executive adopts a general
policy of non-enforcement “which is in effect an abdication of its statutory duty.”88
Selective Prosecution
In discussing the scope of the executive branch’s prosecutorial discretion, courts have repeatedly
noted that the determination as to whether to prosecute may not be “deliberately based upon an
unjustifiable standard such as race, religion, or other arbitrary classification,”89 including the
exercise of protected statutory and constitutional rights.90 Prosecutions (or other enforcement
actions) that are based upon these factors could potentially be found to be impermissible, as was
the case in Yick Wo v. Hopkins. There, the Supreme Court found that prosecutors’ practice of
enforcing a state law prohibiting the operation of laundries against only persons of Chinese
descent ran afoul of the Equal Protection Clause.91 In practice, however, defendants generally find
it difficult to maintain a claim of selective prosecution because of the executive branch’s
prosecutorial discretion. Because such claims are seen as “invad[ing] a special province of the
Executive,” courts generally require defendants to introduce “clear evidence” displacing the
presumption that the prosecutor has acted lawfully.92 Specifically, they must show that (1) they
were singled out for prosecution on an impermissible basis; (2) the government had a policy of
declining to prosecute similarly situated defendants of other races, religions, etc.; and (3) the
policy was motivated by a discriminatory purpose.93

(...continued)
that implicate foreign relations.”).
87 Texas, 106 F.3d at 665 (dismissing a state’s suit alleging that the federal government had violated the constitution
and the INA by failing to control illegal immigration, in part, on the grounds that it was a political question). The
political question doctrine is based on the notion that courts should refrain from deciding questions that the
Constitution has entrusted to other branches of government. See, e.g., Marbury v. Madison, 5 U.S. (1 Cr.) 137, 170
(1803). In determining whether a case entails a political question, courts consider whether there is “[1] a textually
demonstrable constitutional commitment of the issue to a coordinate political department; or [2] a lack of judicially
discoverable and manageable standards for resolving it,” among other things. Baker v. Carr, 369 U.S. 186, 217 (1962).
88 Adams, 480 F.2d at 1162. See also Heckler, 470 U.S. at 832-33 n.4 (finding that judicial review of exercises of
enforcement discretion could potentially be obtained in cases where an agency has adopted a general policy that is an
“abdication of its statutory responsibilities”).
89 Bordenkircher v. Hayes, 434 U.S. 357, 364 (1977) (finding that a state prosecutor’s decision to indict the defendant
as habitual offender after he refused to plead guilty of a felony did not violate the defendant’s constitutional rights).
90 Goodwin, 457 U.S. at 372.
91 118 U.S. 356 (1886).
92 Reno, 525 U.S. at 489 (quoting Armstrong, 517 U.S. at 463).
93 Armstrong, 517 U.S. at 465.
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Claims of selective prosecution can be even more difficult to maintain in an immigration context
because the various prudential concerns that prompt deference to the executive branch’s
determinations as to whether to prosecute particular criminal offenses are “greatly magnified in
the deportation context.”94 In fact, in Reno v. American-Arab Anti-Discrimination Committee,
discussed above, the Supreme Court effectively foreclosed many claims of selective prosecution
in removal proceedings by finding that “[a]s a general matter … an alien unlawfully in this
country has no constitutional right to assert selective enforcement as a defense against his
deportation.”95 The petitioners in Reno had alleged that they were targeted for deportation
because of the exercise of their First Amendment rights. All belonged to a group that the
government characterized as an “international terrorist and communist organization,” and they
asserted that the INS did not enforce “routine status requirements,” such as were enforced against
them, against aliens who were not members of similarly disfavored groups.96 However, a majority
of the Court rejected the petitioners’ arguments, in part, because it viewed “selective prosecution”
as unusual even in the criminal context97 and, in part, because it considered the exercise of
prosecutorial discretion to be particularly significant in the immigration context, as previously
noted. However, the Reno Court did leave open the possibility that a decision to remove an alien
could potentially be struck down in a “rare case in which the alleged basis of discrimination is so
outrageous that the foregoing considerations can be overcome,”98 and subsequent cases continue
to recognize the possibility of selective prosecution claims in the immigration context.99
“Take Care” Clause
Article II, Section 3 of the U.S. Constitution could also potentially constrain the executive
branch’s prosecutorial discretion in certain cases. When discussing the scope of such discretion,
some courts have suggested that situations could potentially arise where the executive branch
“expressly adopt[s] a general policy which is in effect an abdication of its statutory duty” by
implementing a blanket ban on enforcement of a duly enacted statute.100 In such situations, by
refusing to enforce certain aspects of a statute, the executive branch could potentially be said to
have exceeded the permissible scope of prosecutorial or enforcement discretion, and violated the
President’s duty that the “laws be faithfully executed.”101 However, no court appears to have
invalidated a policy of non-enforcement founded upon prosecutorial discretion on the grounds
that the policy violated the Take Care Clause, and one federal appellate court has opined that
“[r]eal or perceived inadequate enforcement ... does not constitute a reviewable abdication of
duty.”102 Rather, according to this court, to prove such an abdication, plaintiffs must show that the

94 Reno, 525 U.S. at 490. It should be noted, however, that the Reno Court did not hold that discriminatory enforcement
of the immigration laws does not offend the Equal Protection Clause, only that Section 242(g) of the INA (8 U.S.C.
§1252(g)) deprives the courts of jurisdiction over such claims.
95 Reno, 525 U.S. at 488.
96 Id. at 473.
97 Id. at 489 (“Even in the criminal-law field, a selective prosecution claim is a rara avis [rare bird].”).
98 Reno, 525 U.S. at 491.
99 See, e.g., Matter of E-R-M & L-R-M, 25 I. & N. Dec. at 522.
100 Adams, 480 F.2d at 1162.
101 U.S. Const. art. II, §3. See also Kendall v. United States ex rel. Stokes, 37 U.S. 524, 613 (“To contend that the
obligation imposed on the President to see the laws faithfully executed, implies a power to forbid their execution, is a
novel construction of the constitution, and entirely inadmissible.”).
102 Texas, 106 F.3d at 667.
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Executive either is “doing nothing to enforce the ... laws,” or has “consciously decided to
abdicate” its enforcement responsibilities.103
Some commentators have suggested that prosecutorial discretion policies which could result in
the executive branch not enforcing the law against a large number of people constitute an
abdication of statutory duty and, thus, violate the Take Care Clause.104 This point has recently
been made by some commentators with respect to the potentially 1.76 million individuals eligible
to receive deferred action under DACA.105 However, even if the INA were construed to impose a
statutory duty to remove all unauthorized aliens, the fact that a large number of persons are
favorably affected by a prosecutorial discretion policy might not, per se, suffice to prove a
violation of the Take Care Clause. Courts might also consider the size of the total population
against whom the law could be enforced, as well as the resources available for enforcing the law,
on the theory that
the President cannot secure full execution of the laws, if Congress denies to him adequate
means of doing so. ... The President performs his full constitutional duty, if, with the means
and instruments provided by Congress and within the limitations prescribed by it, he uses his
best endeavors to secure the faithful execution of the laws enacted.106
Thus, in the case of DACA, for example, a reviewing court might note that DACA-eligible aliens
represent a fraction of the estimated 11.5 million aliens who are present in the United States
without authorization,107 and ICE has the resources to remove annually less than four percent of
the unauthorized alien population.108
The specific form of discretion exercised could also potentially play a role in a reviewing court’s
analysis of whether particular nonenforcement policies or practices constitute an abdication of a
statutory duty. For example, a court could potentially distinguish between determinations to delay
enforcement actions
(e.g., granting deferred action or extended voluntary departure for a
particular duration of time), and determinations not to take enforcement actions (e.g., determining

103 Id.
104 See, e.g., Crane, Amended Complaint, supra note 3, at ¶ 101 (“The application of ‘deferred action’ to approximately
15% of aliens who are in the United States without authorization is not an exercise of executive branch discretion
permitted by the Constitution.”); The Obama Administration, the DREAM Act, and the Take Care Clause, supra note
3, at 2 (“[I]f a President can refuse to enforce a federal law against a class of 800,000 to 1.76 million, what discernible
limits are there to prosecutorial discretion?”).
105 Jeanne Batalova and Michelle Mittelstadt, Migration Policy Institute, Relief from Deportation: Demographic Profile
of DREAMers Potentially Eligible under the Deferred Action Policy, Aug. 2012, available at
http://www.migrationpolicy.org/pubs/FS24_deferredaction.pdf, at 1.
106 Myers v. United States, 272 U.S. 52, 291-92 (1926) (Brandeis, J., dissenting). See also Heckler, 470 U.S. at 831
(noting that, among the factors that make agency decisions to refuse enforcement generally unsuitable for judicial
review, are questions as to “whether agency resources are best spent on this violation or another, ... whether the
particular enforcement action requested best fits the agency’s overall policies, and ... whether the agency has enough
resources to undertake the action at all”).
107 See, e.g., Michael Hoefer, Nancy Rytina, and Bryan Baker, DHS Office of Immigration Statistics, Estimates of the
Unauthorized Immigrant Population Residing in the United States: January 2011, Population Estimates (Mar. 2012),
available at http://www.dhs.gov/xlibrary/assets/statistics/publications/ois_ill_pe_2011.pdf.
108 Civil Immigration Enforcement, supra note 8, at 1 (“ICE ... only has resources to remove approximately 400,000
aliens per year, less than 4 percent of the estimated illegal alien population in the United States.”); Defendants’ Motion
to Dismiss and Memorandum in Support, supra note 36, at 19 (“Deferring action for certain childhood arrivals means
nothing more than that the Department will shift its limited resources to focus on its highest removal priorities, which
include, per Congress’s directive, a focus on criminal aliens and other aliens who threaten public safety.”).
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whether to commence removal proceedings or cancel a notice for an alien to appear at removal
proceedings), on the grounds that the Executive contemplates taking action in the future in the
former cases.109 Relatedly, a reviewing court might note whether the executive branch exercises
its discretion on a case-by-case basis, taking into consideration the specific circumstances of the
offense and the individual who committed it, or whether it has indicated its intention not to
enforce particular offenses at all or against large groups of people. Such distinctions might,
however, be difficult to draw with practices like the DACA initiative, in which exercises of
discretion could be characterized as either individualized or categorical, depending upon how the
initiative is viewed. DHS has repeatedly noted that determinations regarding whether to grant
deferred action are to be made on a case-by-case basis for DACA-eligible individuals.110
However, DHS has also established a broad category of individuals (e.g., those who came to the
United States when they were under the age of 16, and are either currently in school or have
graduated from high school) who are eligible to request deferred action pursuant to DACA.111
The existence of multiple—sometimes inconsistent—enforcement mandates from Congress might
also factor into a court’s analysis of whether particular nonenforcement policies or practices
constitute an abdication of duty, particularly in situations where an agency elects to concentrate
limited resources upon offenders (or offenses) that Congress has recently indicated are a priority.
For example, following the enactment of the Illegal Immigration Reform and Immigrant
Responsibility Act (IIRIRA), which some commentators assert amended the INA to require the
removal of at least some unauthorized aliens, Congress enacted a number of measures directing
DHS to give priority to the removal of “criminal aliens.”112 DHS has emphasized that its
diminished focus on the removal of DACA-eligible individuals corresponds to an increased focus
on criminal aliens,113 and a reviewing court could potentially find that enforcement of later-

109 The Executive could also potentially still take enforcement action in the latter cases by, for example, commencing
removal proceedings against aliens whom it had previously decided not to bring proceedings against. There is no
statute of limitations for the removal of unlawfully present aliens, so those who currently are removable on the grounds
that they are present without authorization would generally still be removable on these grounds in the future. However,
by remaining in the country for a longer period of time, aliens who are present without authorization could potentially
acquire new bases for adjusting status (e.g., marrying a U.S. citizen or lawful permanent resident), as the Court noted in
Reno. 525 U.S. at 490. In addition, at least at some times previously, the immigration agencies had policies of not
taking action against persons whom they had previously determined warranted favorable exercises of prosecutorial
discretion unless the alien’s circumstances had changed. See 2002 INS Guidance, supra note 2, at 11-12 (noting that
favorable exercises of discretion are to be “clearly documented” in the alien’s file, and that an INS office should
generally abide by a favorable decision taken by another office on a matter, absent new or changed circumstances).
110 Exercising Prosecutorial Discretion with Respect to Individuals Who Came to the United States as Children, supra
note 10, at 2 (“No individual should receive deferred action under this memorandum unless they first pass a
background check and requests for relief pursuant to this memorandum are to be decided on a case by case basis. DHS
cannot provide any assurance that relief will be granted in all cases.”).
111 Individuals who do not meet these criteria could still request or be granted deferred action outside of DACA.
112 See, e.g., Department of Homeland Security Appropriations Act, 2012, P.L. 112-74, Div. D., tit. ii, 125 Stat. 950
(Dec. 23, 2011) (“[T]he Secretary of Homeland Security shall prioritize the identification and removal of aliens
convicted of a crime by the severity of that crime.”); Department of Homeland Security Appropriations Act, 2010, P.L.
111-83, Div. D., tit. III, 123 Stat. 2142 (Oct. 28, 2009) (same); Department of Homeland Security Appropriations Act,
P.L. 110-329, Div. D, tit. ii, 122 Stat. 3659 (Sept. 30, 2008) (same); Consolidated Appropriations Act, 2008, P.L. 110-
161, 121 Stat. 2050-51 (Dec. 26, 2007) (funding to “improve and modernize efforts to identify aliens convicted of a
crime, sentenced to imprisonment, and who may be deportable, and remove them from the United States”); H.R. REPT.
111-157, at 6 (2009) (“[R]ather than simply rounding up as many illegal immigrants as possible, which is sometimes
achieved by targeting the easiest and least threatening among the undocumented population, DHS must ensure that the
government’s huge investments in immigration enforcement are producing the maximum return in making our country
safer.”).
113 See, e.g., Civil Immigration Enforcement, supra note 8, at 1-2 (aliens who have been convicted of crimes, are at
(continued...)
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enacted mandates (as to criminal aliens) may justify more limited enforcement of earlier enacted
mandates (as to unauthorized aliens generally).
Statute
Another potential constraint upon the executive branch’s exercise of prosecutorial discretion was
noted by the Supreme Court in Heckler v. Cheney. There, the Court rejected a challenge to the
Food and Drug Administration’s (FDA’s) decision not to exercise its enforcement authority over
the use of certain drugs on the grounds that “an agency’s decision not to take enforcement action
should be presumed immune from judicial review under § 701(a)(2)” of the Administrative
Procedure Act (APA).114 Section 701(a)(2) of the APA generally bars review of “agency action
[that] is committed to agency discretion by law,”115 and the Court’s statement here would suggest
that it views exercises of prosecutorial discretion as generally committed to agency discretion by
law. However, the Heckler Court also noted that this presumption of nonreviewability “may be
rebutted where the substantive statute has provided guidelines for the agency to follow in
exercising its enforcement powers.”116
Determining whether a statute provides “guidelines” so as to make an agency’s determination not
to take enforcement action reviewable generally implicates questions of statutory interpretation.
Such questions are not necessarily easily answered, though, as is illustrated by the argument that
the executive branch lacks the discretion to grant deferred action to DACA beneficiaries because
the INA requires the removal of aliens who entered the United States unlawfully.117 This
argument, which has recently been made by some commentators and litigants, rests upon three
“interlocking provisions” in Section 235 of the INA that were added or amended by IIRIRA.
Briefly summarized, these provisions state that
1. any alien present in the United States who has not been admitted shall be deemed
an applicant for admission;
2. applicants for admission shall be inspected by immigration officers; and
3. in the case of an alien who is an applicant for admission, if the examining
immigration officer determines that an alien seeking admission is not clearly and

(...continued)
least 16 years of age and participate in organized criminal gangs, are subject to outstanding criminal warrants, or
“otherwise pose a serious risk to public safety” constituting the highest priorities for removal). Relatedly, Secretary
Napolitano’s announcement of the DACA initiative expressly excluded from consideration for deferred action under
DACA persons who have been convicted of a felony, a “significant misdemeanor,” or multiple misdemeanors. See
Exercising Prosecutorial Discretion with Respect to Individuals Who Came to the United States as Children, supra note
10, at 1.
114 Heckler, 470 U.S. at 832.
115 5 U.S.C. §701(a)(2). This presumption is an exception to the general rule that the APA “embodi[es] a ‘basic
presumption of judicial review.’” Lincoln v. Vigil, 508 U.S. 182, 190 (1993) (quoting Abbott Labs. v. Gardner, 387
U.S. 136, 140 (1967)).
116 470 U.S. at 832-33. See also id. at 833 (“[I]n establishing this presumption [of nonreviewability] in the APA,
Congress did not set agencies free to disregard legislative direction in the statutory scheme that the agency administers.
Congress may limit an agency’s exercise of enforcement power if it wishes, either by setting substantive priorities, or
by otherwise circumscribing an agency’s power to discriminate among issues or cases it will pursue.”).
117 See, e.g., Arizona v. United States, No. 11-182, Amicus Curiae Brief of Secure States Initiative in Support of
Petitioners, at 8-9; Crane, Amended Complaint, supra note 3, at ¶¶ 38-40.
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beyond a doubt entitled to be admitted, the alien shall be detained for removal
proceedings.118
Those who view these provisions as requiring the removal of aliens who entered the United States
unlawfully would appear to construe “shall” as indicating mandatory agency action, and all
“applicants for admission” as “aliens seeking admission.”
However, alternate interpretations are possible, assuming that the argument that Section 235
removes agency discretion has not been effectively foreclosed by the Supreme Court’s recent
decision in Arizona v. United States.119 While the majority in Arizona did not directly address the
DACA initiative, it expressly noted the “broad discretion exercised by immigration officials” in
the removal process.120 Because such discretion would arguably be inconsistent with a statutory
requirement to place in removal proceedings all aliens who entered the United States unlawfully,
the majority’s decision suggests that the Court does not construe the INA as legally compelling
immigration officers to place all aliens who entered the United States unlawfully in removal
proceedings.
Whether “Shall” Means Agencies Lack Discretion
The argument that Section 235 of the INA requires that aliens who unlawfully entered the United
States be placed in removal proceedings appears to rest, in part, on the use of “shall” in Section
235, and the view that “shall” indicates mandatory agency action. “Shall” frequently indicates
required action, particularly when used in contexts that do not implicate an agency’s enforcement
discretion.121 However, its use in Section 235 would not necessarily be construed to mean that
DHS is required to commence proceedings against aliens who entered the United States

118 INA §235(a)(1), (a)(3), and (b)(2)(A); 8 U.S.C. §1225(a)(1), (a)(3), and (b)(2)(A).
119 Moreover, even if a reviewing court construed Section 235 of the INA as statutorily compelling DHS to place aliens
who unlawfully entered the United States into removal proceedings, DHS would not necessarily be barred from
exercising certain forms of prosecutorial discretion as to DACA beneficiaries after these individuals have been placed
into removal proceedings. See generally Crane, Amended Complaint, supra 3, at ¶ 71 (“[A]ny ‘prosecutorial
discretion’ that Defendants exercise must be consistent with 8 U.S.C. § 1225 and can only occur after an alien has been
placed into removal proceedings as required by 8 U.S.C. §1225, or under a provision of federal law expressly
authorizing such ‘prosecutorial discretion.’”).
120 Arizona, 132 S. Ct. at 2499 (“A principal feature of the removal system is the broad discretion exercised by
immigration officials. Federal officials, as an initial matter, must decide whether it makes sense to pursue removal at
all. If removal proceedings commence, aliens may seek asylum and other discretionary relief allowing them to remain
in the country or at least to leave without formal removal. Discretion in the enforcement of immigration law embraces
immediate human concerns. … Some discretionary decisions [also] involve policy choices that bear on this Nation’s
international relations. ... The dynamic nature of relations with other countries requires the Executive Branch to ensure
that enforcement policies are consistent with this Nation’s foreign policy with respect to these and other realities.”)
(internal citations omitted)).
121 See, e.g., Lopez v. Davis, 531 U.S. 230, 241 (2001) (“Congress’ use of the permissive ‘may’ in § 3621(e)(2)(B)
contrasts with the legislators’ use of a mandatory ‘shall’ in the very same section. Elsewhere in § 3621, Congress used
‘shall’ to impose discretionless obligations, including the obligation to provide drug treatment when funds are
available. See 18 U.S.C. § 3621(e)(1) (‘Bureau of Prisons shall, subject to the availability of appropriations, provide
residential substance abuse treatment (and make arrangements for appropriate aftercare)’); see also, e.g., § 3621(b)
(‘The Bureau shall designate the place of the prisoner’s imprisonment.... In designating the place of imprisonment or
making transfers under this subsection, there shall be no favoritism given to prisoners of high social or economic
status.’”).
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unlawfully, because courts have found that agencies may retain discretion even when a statute
uses “shall.”122 The statute at issue in Heckler, for example, stated that
[a]ny article of food, drug, or cosmetic that is adulterated or misbranded when introduced
into or while in interstate commerce or while held for sale ... after shipment in interstate
commerce, or which may not ... be introduced into interstate commerce, shall be liable to be
proceeded against.123
Nonetheless, despite its use of “shall,” this statutory provision was construed by the Court as
“framed in the permissive.”124 The Board of Immigration Appeals (BIA), the highest
administrative body for construing and applying immigration law, has also rejected the view that
“shall” means that immigration officials necessarily lack discretion as to whether to take
particular actions. For example, in a recent decision, the BIA found that determinations as to
whether to pursue expedited removal proceedings under Section 235 of the INA or formal
removal proceedings under Section 240 of the INA are within DHS’s discretion, notwithstanding
the fact that the INA uses “shall” in describing who is subject to expedited removal.125 In so
doing, the BIA specifically noted that
in the Federal criminal code, Congress has defined most crimes by providing that whoever
engages in certain conduct “shall” be imprisoned or otherwise punished. But this has never
been construed to require a Federal prosecutor to bring charges against every person believed
to have violated the statute.126
In light of these precedents, the use of “shall,” in itself, might not suffice for a court to find that
an agency lacks the discretion not to enforce particular statutory requirements against certain
individuals. Rather, a reviewing court might also consider the overall “statutory scheme [and] its
objectives.”127 For example, in Dunlop v. Bachowski, the Court found that the Department of
Labor’s alleged nonenforcement of a statute was reviewable, unlike with the statute at issue in
Heckler. The statute in question used the word “shall,” but the Court does not appear to have
accorded any special significance to this word. Instead, the Court emphasized that the statute
directed the Secretary of Labor to investigate certain complaints brought by members of labor
organizations challenging the validity of union elections, and bring a civil action against the labor
organization within 60 days of the complaint’s filing if the Secretary finds probable cause to
believe a violation occurred and has not been remedied.128 Because of these provisions, the Court
viewed the Secretary’s discretion as limited to determining whether there is probable cause to

122 INS and, later, DHS has also taken the position that the use of “shall” in a statute does not, by itself, limit the ability
of immigration officers to exercise prosecutorial discretion, and the agencies’ views could potentially be entitled to
some deference, as discussed below. See, e.g., 2002 INS Guidance, supra note 2 (“[A] statute directing that the INS
‘shall’ remove removable aliens would not be construed by itself to limit prosecutorial discretion.”); INS Exercise of
Prosecutorial Discretion, supra note 15, at 8 (opining that any statutory limits on INS’s prosecutorial discretion must be
“clear and specific”).
123 470 U.S. at 835 (quoting 21 U.S.C. §334(a)(1) (emphasis added)).
124 Id. See also id. at 842 (Marshall, J., concurring) (indicating that the Food, Drug, and Cosmetics Act is “not a
mandatory statute” and, thus, the Food and Drug Administration has “significant discretion” to choose which alleged
violations to prosecute).
125 Matter of E-R-M & L-R-M, 25 I. & N. Dec. 520, 523 (BIA 2011).
126 Id. at 522.
127 Dunlop v. Bachowski, 421 U.S. 560, 567 (1975) (also considering the legislative history and the “nature of the
administrative action involved”).
128 Id. at 563.
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believe that a violation occurred.129 Similarly, in Adams v. Richardson, the U.S. Court of Appeals
for the District of Columbia Circuit noted that the statute in question was not “so broad” as to
preclude judicial review, since it “indicates with precision the measures available to enforce the
Act.”130
Deference to Agencies’ Interpretations of Their Governing Statutes
Another potential difficulty with construing Section 235 of the INA as requiring the removal of
aliens who unlawfully entered the United States arises from the fact that the Department of
Justice (DOJ) and, later, DHS have interpreted the relevant provisions of the INA in a somewhat
different manner, and the agencies’ interpretation could potentially be entitled to deference under
the precedent of Chevron, USA v. Natural Resources Defense Council.131 In Chevron, the
Supreme Court articulated a two-part test for review of an agency’s construction of a statute
which it administers: (1) Has Congress directly spoken to the precise question at issue? and (2) If
not, is the agency’s reasonable interpretation of the statute consistent with the purposes of the
statute?132 “[I]f the statute speaks clearly ‘to the precise question at issue,’” the tribunal “must
give effect to the unambiguously expressed intent of Congress,”133 regardless of what the agency
regulation provides. However, where “the statute is silent or ambiguous with respect to the
specific issue,” the tribunal “must sustain the [a]gency’s interpretation if it is ‘based on a
permissible construction’ of the Act.”134
Like those who argue that DHS lacks the discretion not to remove aliens who entered the United
States unlawfully, DOJ and DHS have construed the first two provisions of Section 235 of the
INA noted above—aliens present without admission being deemed applicants for admission, and
applicants for admission being inspected—as applying to both (1) “arriving aliens” at a port-of-
entry and (2) aliens who are present in the United States without inspection. However, DOJ and
DHS have differed from proponents of the view that DHS lacks discretion in that DOJ and DHS
have construed the third provision—regarding detention of certain aliens seeking admission—as
applicable only to arriving aliens, not aliens who are present without inspection.135 This difference

129 Id. at 570.
130 480 F.2d at 1162. See also id. at 1163 (noting that “[t]he Act sets forth two alternative courses of action by which
enforcement may be effected”).
131 467 U.S. 837 (1984). A case recently argued before the Supreme Court, City of Arlington v. FCC, has raised the
question of whether a court should apply Chevron to an agency’s determination of its own jurisdiction. However, the
outcome of this case seems may not affect the discussion of here, since the primary issue in this case would appear to
be the degree of deference to be accorded to DHS regulations that distinguish between aliens seeking admission and
arriving aliens.
132 467 U.S. at 842-43.
133 Barnhart v. Walton, 535 U.S. 212, 217 (2002) (quoting Chevron, 467 U.S. at 842-43).
134 Id. at 218 (quoting, in part, Chevron, 467 U.S. at 843).
135 Specifically, the regulation implementing the third INA provision noted above—regarding the detention of aliens
seeking admission—applies only to arriving aliens, not to aliens who entered without admission. See 8 C.F.R.
§235.3(c) (“[A]ny arriving alien who appears to the inspecting officer to be inadmissible, and who is placed in removal
proceedings pursuant to section 240 of the Act shall be detained in accordance with section 235(b) of the Act”). This
has been the agency’s interpretation of the provision since the initial final rule implementing this provision. See INS,
Inspection and Expedited Removal of Aliens; Detention and Removal of Aliens; Conduct of Removal Proceedings;
Asylum Procedures, 62 Fed. Reg. 10312, 10357 (Mar. 6, 1997) (codified at 8 C.F.R. §235.3(c)). See also INS,
Inspection and Expedited Removal of Aliens; Detention and Removal of Aliens; Conduct of Removal Proceedings;
Asylum Procedures, 62 Fed. Reg. 444, 444-46 (Jan. 3, 1997) (noting that the INA “distinguishes between the broader
term ‘applicants for admission’ and a narrower group, ‘arriving aliens’”). The term “arriving alien” is defined in the
(continued...)
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appears to have arisen, in part, because the agencies have emphasized the phrase “aliens seeking
admission” in the third provision, and have reasoned that only arriving aliens at ports-of-entry can
be said to be seeking admission.
The position of DHS and DOJ may also reflect concerns that if Section 235(b)(2)(A) were
construed to apply to all applicants for admission, the statutory language regarding “seeking
admission” would be superfluous, and construing statutes so as to give effect to all of their
provisions is one of the fundamental principles of statutory interpretation.136 Similarly, if
detention were mandatory for all applicants for admission under INA 235(b)(2)(A), then the
language including inadmissible aliens under the mandatory detention provision in Section
236(c)(1)(A) and (D) of the INA would arguably be superfluous as well, since the only aliens in
the United States who are subject to the grounds of inadmissability are applicants for admission.
The agencies’ interpretation does not appear to have been directly adopted by any court, although
it arguably has been implicitly adopted in various court and BIA rulings that have applied a DHS
regulation which provides that immigration judges have jurisdiction over bond determinations for
aliens present without inspection, but not for arriving aliens.137
It should be noted, however, that the INS and, later, DHS have construed other provisions of the
INA as removing their prosecutorial discretion as to certain determinations. For example,
immigration authorities have long maintained that Section 236(c) of the INA—which states that
immigration officials “shall take into custody” certain criminal aliens, and may release them only
under narrow circumstances138—limits their discretion as to whether or not to release such aliens
from custody.139
Executive Branch Self-Regulation
An agency could also potentially be found to have imposed certain constraints upon its exercise
of prosecutorial discretion through either (1) the promulgation of regulations or (2) the issuance
of guidelines that the agency intends to be binding or which have been employed in such a way as

(...continued)
regulations as “an applicant for admission coming or attempting to come into the United States at a port-of-entry, or an
alien seeking transit through the United States at a port-of-entry, or an alien interdicted in international or United States
waters and brought into the United States,” but does not include aliens who entered without inspection. See 8 C.F.R.
§1.2.
136 See, e.g., Hibbs v. Winn, 542 U.S. 88, 101 (2004) (“A statute should be construed so that effect is given to all its
provisions, so that no part will be inoperative or superfluous, void or insignificant.”); Montclair v. Ramsdell, 107 U.S.
147, 152 (1883) (Courts should “give effect, if possible, to every clause and word of a statute, avoiding, if it may be,
any construction which implies that the legislature was ignorant of the meaning of the language it employed.”).
137 See, e.g., 8 C.F.R. §236.1(c) & (d); Matter of Oseiwusu, 22 I. & N. Dec. 19 (BIA 1998) (“According to the
regulations, an Immigration Judge has no authority over the apprehension, custody, and detention of arriving aliens and
is therefore without authority to consider the bond request of an alien returning pursuant to a grant of advance parole.”).
138 INA §236(c)(1)-(2); 8 U.S.C. §1226(c)(1)-(2).
139 See, e.g., 2002 INS Guidance, supra note 2, at 3 (indicating that detention pursuant to Section 236(c) is mandatory
because Section 236(c) “evidences a specific congressional intention to limit discretion not to detain certain criminal
aliens in removal proceedings that would otherwise exist”); INS Exercise of Prosecutorial Discretion, supra note 15, at
11. However, some commentators have noted that, notwithstanding this view, immigration agencies have released
aliens subject to “mandatory detention” in order to moot lawsuits challenging the alien’s detention. See, e.g., Stephen
H. Legomsky, The Detention of Aliens: Theories, Rules, and Discretion, 30 U. MIAMI INTER-AM. L. REV. 531, 534
(1999).
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to be binding as a practical matter.140 For example, in a 1979 decision, the U.S. Court of Appeals
for the Ninth Circuit (“Ninth Circuit”) found that an INS Operations Instruction addressing
deferred action against deportable aliens was binding upon the agency because of its “purpose
and effect.”141 In reaching this conclusion, the court emphasized that the Instruction more closely
resembled a substantive provision for relief than an internal procedural guideline because it
“exist[ed] out of consideration for the convenience of the petitioner, and not that of the INS.”142
The court further noted that the Instruction ostensibly required INS district directors to
recommend deferred or “non-priority” status in certain cases, and that this status was periodically
reviewed and not subject to termination at INS’s convenience.143 In short, the court distinguished
the Instruction from other intra-agency guidelines that would create no substantive rights because
the Instruction’s effects were “final and permanent, with the same force as that of a Congressional
statute.”144 Other courts reached different conclusions as to whether this particular Operations
Instruction was binding,145 and the INS subsequently amended to it to clarify that grants of
deferred action were discretionary.146 Later, the guideline was rescinded (although INS and, later,
DHS continued to grant deferred action).147 However, the 1979 case illustrates that certain types
of “cabining of an agency’s prosecutorial discretion” could potentially “rise to the level of a
substantive, legislative rule” in the immigration context.148 Were that the case, DHS’s exercise of
prosecutorial discretion could potentially be found to have been constrained by its own
guidelines.

140 See, e.g., Pacific Molasses Co. v. Fed. Trade Comm'n, 356 F.2d 386, 389-90 (5th Cir. 1996) (“When an
administrative agency promulgates rules to govern its proceedings, these rules must be scrupulously observed. This is
so even when the defined procedures are ‘… generous beyond the requirements that bind such agency …’ For once an
agency exercises its discretion and creates the procedural rules under which it desires to have its actions judged, it
denies itself the right to violate these rules.”). But see Farrell v. Dep’t of the Interior, 314 F.3d 584, 590 (Fed. Cir.
2002) (“The general consensus is that an agency statement, not issued as a formal regulation, binds the agency only if
the agency intended the statement to be binding.”).
141 Nicholas v. INS, 590 F.2d 802, 805 (1979).
142 Id. at 807.
143 Id.
144 Id.
145 See, e.g., Vergel v. INS, 536 F.2d 755, 757-80 (8th Cir. 1976) (upholding the deportation order, but staying its
mandate for a period of time to allow the alien to apply for deferred action); David v. INS, 548 F.2d 219, 223 (8th Cir.
1977) (same); Yoon v. INS, 538 F.2d 1211, 1213 (5th Cir. 1976) (decision to grant or deny deferred action was within
the “particular discretion of the INS,” and the agency had the power to create and employ a category “for its own
administrative convenience without standardizing the category and allowing applications for inclusion in it”); Lennon
v. INS, 527 F.2d 187, 191 n.7 (2nd Cir. 1975) (describing deferred action as an “informal administrative stay of
deportation”).
146 See, e.g., Leon Wildes, The Deferred Action Program of the Bureau of Citizenship and Immigration Services: A
Possible Remedy for Impossible Immigration Cases
, 41 SAN DIEGO L. REV. 819, 822 (2004).
147 See, e.g., Charles Gordon, Stanley Mailman, & Stephen Yale-Loehr, IMMIGR. L. & PROC. §72.03(2)(h) n.120 (2009)
(noting that the Operating Instruction addressing deferred action was rescinded in 1997).
148 Community Nutrition Institute v. Young, 818 F.2d 943, 948 (1987) (finding that the FDA’s thresholds for aflatoxins
in corn were legislative rules that should have been promulgated through notice-and-comment rulemaking because the
levels “have a present effect and are binding,” and marketing any food not within the levels is viewed as unlawful). But
see Heckler
, 470 U.S. at 837 (rejecting a challenge to the Food and Drug Administration’s refusal to enforce alleged
violations of the Food, Drug, and Cosmetic Act, in part, because the agency “policy statement” in question did not
“arise in the course of discussing the agency’s discretion to exercise its enforcement power” and, thus, did not limit this
discretion). The Court in Heckler expressly left open the possibility that certain agency rules might provide adequate
guidelines for informed judicial review of decisions not to enforce them. Id. at 836.
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In its recent guidance regarding the exercise of prosecutorial discretion, DHS has consistently
emphasized that “there is no right to a favorable exercise of prosecutorial discretion by the
agency,” and that nothing in the guidelines should be construed to prohibit the apprehension,
detention, or removal of aliens unlawfully present in the United States, or to limit any legal
authority to enforce federal immigration law.149 However, an agency’s characterization of its own
policies as non-binding is not necessarily dispositive,150 and certain parties challenging the DACA
initiative have recently suggested that, in “implementing the Directive, DHS has treated the
Directive as if it were a rule.”151 No court appears to have addressed this argument, to date, but
early in 2012—when DHS was conducting preliminary reviews of the dockets of the immigration
courts in Baltimore and Denver for cases that might qualify for favorable exercises of
prosecutorial discretion152—a panel of the Ninth Circuit ordered ICE to advise the court as to
whether ICE planned to exercise prosecutorial discretion in five pending cases.153 The court did
so sua sponte, without such an order having been requested, and the dissenting judge expressed
concern that the majority’s order could portend future scrutiny of why ICE made particular
decisions.154 The dissent also asserted that judicial review of ICE’s exercise of prosecutorial
discretion is “sharply limited by the separation of powers.”155
Conclusion
Regardless of whether it is characterized as “prosecutorial discretion” or “enforcement
discretion,” immigration officers are generally seen as having wide latitude in determining when,
how, and even whether to pursue apparent violations of the INA. This latitude is similar to that
possessed by prosecutors in the criminal law enforcement context and enforcement officials in
other federal agencies. Whether and how to constrain this discretion has been a recurring issue for

149 See, e.g., 2011 DHS Guidance, supra note 9, at 6.
150 See, e.g., Columbia Broadcasting Sys., Inc. v. United States, 316 U.S. 407, 416 (1942) (“The particular label placed
upon it by the Commission is not necessarily conclusive, for it is the substance of what the Commission has purported
to do and has done which is decisive.”); Guardian Fed. Savings & Loan Ass’n v. Fed. Savings & Loan Ins. Corp., 589
F.2d 658, 666-67 (D.C. Cir. 1978) (“If it appears that a so-called policy statement is in purpose or likely effect one that
narrowly limits administrative discretion, it will be taken for what it is—a binding rule of substantive law.”). The
agency’s characterization could, however, potentially be entitled to some deference. See, e.g., Community Nutrition
Institute
, 818 F.2d at 946.
151 Crane v. Napolitano, No. 3:12-cv-03247-O, Brief in Support of Plaintiffs’ Application for Preliminary Injunction, at
19 (filed N.D. Tex., Nov. 28, 2012). See also Crane v. Napolitano, No. 3:12-cv-03247-O, Affidavit of Christopher L.
Crane, ¶ 8 (filed N.D. Tex., Nov. 27, 2012) (alleging that ICE has adopted a practice of not questioning individuals
who assert that they could be eligible for deferred action as part of the DACA initiative, thereby effectively making all
who claim deferred action entitled to it).
152 See, e.g., Julia Preston, U.S. to Review Cases Seeking Deportations, New York Times, Nov. 17, 2011, available at
http://www.nytimes.com/2011/11/17/us/deportation-cases-of-illegal-immigrants-to-be-reviewed.html.
153 Rodriguez v. Holder, 668 F.3d 670 (9th Cir. 2012); Agustin v. Holder, 668 F.3d 672 (9th Cir. 2012); Jex v. Holder,
668 F.3d 673 (9th Cir. 2012); Pocasangre v. Holder, 668 F.3d 674 (9th Cir. 2012); Mata-Fasardo v. Holder, 668 F.3d
674 (9th Cir. 2012).
154 Agustin, 668 F.3d at 672 (O’Scannlain, J., dissenting).
155 Id. More recently, in response to the DACA initiative, the U.S. Court of Appeals for the Second Circuit (“Second
Circuit”) established a procedure whereby pending immigration cases are tolled while the government determines
whether to remand the case to the BIA for administrative closure in light of DACA and related initiatives. In Matter of
Immigration Petitions for Review Pending in the United States Court of Appeals for the Second Circuit
, No. 12-4096,
2012 U.S. App. LEXIS 21555 (Oct. 16, 2012). However, unlike the Ninth Circuit, the Second Circuit did not order ICE
to inform it regarding whether ICE plans to exercise discretion in particular cases.
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some Members of Congress, particularly in light of the June 2011 DHS memorandum on
prosecutorial discretion and the more recent DACA initiative.156 While some Members have
expressed support for the DACA initiative,157 or called for expanded use of prosecutorial
discretion by immigration authorities in other contexts,158 others have sought to prohibit DHS
from granting deferred action or extended voluntary departure to removable aliens except in
narrow circumstances,159 or to “nullify” particular policies regarding prosecutorial discretion that
have been articulated by the Obama Administration.160
The extent to which Congress can constrain the Administration’s exercise of discretion in the
DACA context, in particular, may depend on whether a reviewing court characterizes the
underlying authority for the implementation of the program as constitutionally or statutorily
based. Congress has broad authority to restrict discretionary acts taken pursuant to statutory
delegations, while arguably limited authority, under the doctrine of Separation of Powers, to
restrict the President’s exercise of constitutionally based discretion. In addition, the degree of
intrusion into executive enforcement decisions may also impact a court’s review of any
congressional response. For example, legal precedent suggests that Congress probably cannot
directly limit the President’s exercise of discretion by requiring that the executive branch initiate
enforcement actions against particular individuals.161 On the other hand, Congress would appear
to have considerable latitude in establishing statutory guidelines for immigration officials to
follow in the exercise of their enforcement powers, including by “indicat[ing] with precision the
measures available to enforce the” INA, or by prohibiting DHS from considering certain
characteristic in setting enforcement priorities.162
However, the existing judicial presumption that “an agency’s decision not to take enforcement
action [is] immune from judicial review,”163 and the deference potentially accorded to an agency’s
interpretation of its governing statute,164 suggests that such statutory guidelines would likely need
to be clear, express, and specific. The use of “shall” in a provision of the INA may not, in itself,
suffice for a statute to be construed as having provided enforceable guidelines for immigration
officials to follow in exercising prosecutorial discretion. Absent a substantive legislative

156 See supra note 12 and accompanying text.
157 See, e.g., Durbin Statement on DREAM Act and Administrative Action to Help Young Immigrants, June 15, 2012,
available at http://durbin.senate.gov/public/index.cfm/pressreleases?ID=070d1061-66c4-45ef-bb34-41da7e1e7d40.
158 See, e.g., Pelosi, Nadler, Honda, and 81 Members of Congress Urge Department of Homeland Security Again To
Recognize LGBT Family Ties in Deportation Cases, available at http://honda.house.gov/index.php?option=
com_content&task=view&id=1216&Itemid=110.
159 Hinder the Administration’s Legalization Temptation (HALT) Act, H.R. 2497, §2(f) (permitting the grant of
deferred action or extended voluntary departure only for the purpose of maintaining an alien in the United States “(1) to
be tried for a crime, or to be a witness at trial, upon the request of a Federal, State, or local law enforcement agency; (2)
for any other significant law enforcement or national security purpose; or (3) for a humanitarian purpose where the life
of the alien is imminently threatened”).
160 Prohibiting the Back-Door Amnesty Act, H.R. 5953, §2(a) (“nullifying” the 2011 Morton memoranda and the 2012
Napolitano memorandum, previously discussed).
161 See Heckler, 470 U.S. at 833 (“... Congress did not set agencies free to disregard legislative direction in the statutory
scheme that the agency administers. Congress may limit an agency’s exercise of enforcement power if it wishes, either
by setting substantive priorities, or by otherwise circumscribing an agency’s power to discriminate among issues or
cases it will pursue.”).
162 Adams, 480 F.2d at 1162.
163 Heckler, 470 U.S. at 832.
164 Chevron, 467 U.S. at 842-43.
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response, Congress may still be able to influence the implementation of DACA or other
discretion-based policies by the immigration authorities, including by engaging in stringent
oversight over the DHS program or by exercising its “power of the purse”165 to prohibit DHS and
its components from implementing particular policies related to the exercise of prosecutorial
discretion that Congress does not support.166

Author Contact Information

Kate M. Manuel
Todd Garvey
Legislative Attorney
Legislative Attorney
kmanuel@crs.loc.gov, 7-4477
tgarvey@crs.loc.gov, 7-0174



165 See U.S. Const., art. I, §9, cl. 7 (“No Money shall be drawn from the Treasury, but in Consequence of
Appropriations made by Law.... ”).
166 See, e.g., Department of Homeland Security Appropriations Act, 2013, H.R. 5855, as passed by the House, §581(a)
(“None of the funds made available in this Act may be used to finalize, implement, administer, or enforce the ‘Morton
Memos.’”).
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