November 16, 2022
Congressional Redistricting: Key Legal and Policy Issues
Following each decennial census, the 435 seats in the
deviation from precise equality than state legislative
House are apportioned—or divided up—among the 50
districts are. For example, in
Kirkpatrick v. Preisler (394
states (U.S. Const. amend. XIV, § 2, cl. 1; 2 U.S.C. §
U.S. 526 (1969)), the Court invalidated a congressional
2a(a)). Accordingly, to comport with the constitutional
redistricting plan with a 5.97% maximum population
standard of population equality among districts, discussed
deviation, where the “most populous district was 3.13%
below, at least once every 10 years, most states are required
above the mathematical ideal, and the least populous was
to draw new congressional district boundaries in response
2.84% below.” The Court characterized the variance as too
to changes in the number of Representatives apportioned to
great to comport with the “as nearly as practicable”
the state or shifts in population within the state. This
standard set forth in
Wesberry, requiring the government to
process is known as
congressional redistricting.
“make a good faith effort to achieve precise mathematical
equality.”
Federal Requirements for Congressional
Districts
Section 2 of the Voting Rights Act (VRA) Standard
Most federal standards for congressional redistricting derive
Congressional district boundaries in every state are required
from the Constitution and federal law, as interpreted by the
to comply with Section 2 of the VRA (52 U.S.C. § 10301).
Supreme Court, as discussed below. Under Article I, § 2, cl.
Section 2 prohibits any voting qualification or practice
3 of the Constitution, as amended by the Fourteenth
applied or imposed by any state or political subdivision
Amendment, representation in the House of Representatives
(e.g., a city or county) that results in the denial or
is based on state population size. Article I, § 2, cl. 3 also
abridgement of the right to vote based on race, color, or
requires that each state has at least one Representative and
membership in a language minority. This prohibition
that districts have at least 30,000 persons. 2 U.S.C. § 2c
includes congressional redistricting maps. Section 2 further
requires that one Representative be elected from each
provides that the VRA is violated if, based on the totality of
district.
circumstances, electoral processes are not equally open to
participation by members of a racial or language minority
Population Equality Standard
group in that the group’s members have less opportunity
The Supreme Court has interpreted the Constitution to
than other members of the electorate to elect representatives
require that each congressional district within a state
of their choice.
contain an approximately equal number of persons. In
Wesberry v. Sanders (376 U.S. 1 (1964)), the Court
Under certain circumstances, Section 2 may require the
interpreted Article I, § 2, cl. 1 of the Constitution (that
creation of one or more
majority-minority districts in a
Representatives be chosen “by the People of the several
congressional redistricting map in order to prevent the
States”) to mean that, “as nearly as is practicable[,] one
denial or abridgement of the right to vote based on race,
man’s vote in a congressional election is to be worth as
color, or membership in a language minority. A majority-
much as another’s.” Later that year, in
Reynolds v. Sims
minority district is one in which a racial or language
(377 U.S. 533 (1964)), the Court held that this requirement,
minority group comprises a voting majority. The creation of
or the
population equality standard of one person, one vote,
such districts can avoid minority vote dilution by helping to
also applies in the context of state legislative redistricting
ensure that racial or language minority groups are not
and that the Fourteenth Amendment’s Equal Protection
submerged into the majority and, thereby, denied an equal
Clause requires all who participate in an election “to have
opportunity to elect candidates of choice.
an equal vote.” The population equality standard applies
only to districts within a state and not to districts across
On October 4, 2022, the Supreme Court heard oral
various states.
arguments in a case that could affect standards that
reviewing courts apply in determining when the creation of
Since 1964, the Court has described the extent to which a
a majority-minority district in a congressional redistricting
redistricting plan, in complying with the population equality
map is required under Section 2 of the VRA. In
Merrill v.
standard, may deviate from precise or ideal population
Milligan, the Court is evaluating a challenge to an Alabama
equality among congressional districts within a state.
congressional redistricting map where the lower court
Precise or ideal equality is the average population that each
determined that compliance with Section 2 required the
district would contain if a state’s population were evenly
creation of two majority-minority districts instead of one.
distributed across all districts. The total population
deviation or “maximum population deviation” refers to the
Equal Protection Standard
percentage difference from the ideal population between the
Congressional redistricting maps must also conform with
most and least populated districts in a state. The Court has
standards of equal protection under the Fourteenth
determined that congressional districts are permitted less
Amendment. According to the Supreme Court, if race is the
https://crsreports.congress.gov
Congressional Redistricting: Key Legal and Policy Issues
predominant factor in the drawing of district lines above
Some states also address political competition through their
other traditional redistricting considerations—including
redistricting criteria. For example, 13 states prohibit
compactness, contiguity, and respect for political
districts intended to unduly favor or disfavor an incumbent.
subdivision lines—then courts must apply a “strict
Other criteria related to political parties may be considered
scrutiny” standard of review. To withstand strict scrutiny in
relevant to discussions about partisan gerrymandering.
this context, the state must demonstrate that it had a
Thirteen states, for example, prohibit districts intended to
compelling governmental interest in creating a majority-
unduly favor or disfavor a political party, and five states
minority district and the redistricting plan was narrowly
prohibit use of partisan data in the redistricting process. In
tailored to further that compelling interest (
Cooper v.
other states, use or consideration of party identification in
Harris, 581 U.S. 285 (2017)). Cases challenging
the redistricting process may be allowed.
redistricting plans on such grounds are often referred to as
racial gerrymandering cases because the challengers argue
During its October 2022 term, in
Moore v. Harper, the
that race was improperly used in drawing district
Supreme Court is scheduled to consider the scope of a state
boundaries. Case law in this area has revealed that there can
court’s authority under the Elections Clause to overturn
be tension between complying with the VRA and
laws enacted by a state legislature that regulate
conforming with standards of equal protection.
congressional elections based on state constitutional
provisions. Depending on how the Court rules, the decision
Claims of Partisan Gerrymandering Not Subject to
could clarify under what circumstances state legislatures
Federal Court Review
have the authority to establish congressional redistricting
Partisan gerrymandering is “the drawing of legislative
maps without review by state courts. For more information,
district lines to subordinate adherents of one political party
see CRS Legal Sidebar LSB10838,
State Legislatures, State
and entrench a rival party in power.” In
Rucho v. Common
Courts, and Federal Elections: U.S. Supreme Court to
Cause (139 S. Ct. 2484 (2019)), the Supreme Court ruled
Consider Moore v. Harper, by L. Paige Whitaker.
that claims of unconstitutional partisan gerrymandering are
not subject to federal court review because they present
Considerations for Congress
non-justiciable political questions. The Court viewed the
Although redistricting processes today are largely governed
Elections Clause of the Constitution (Article I, § 4) as
by state law in practice, Congress has, at times, considered
solely assigning disputes about partisan gerrymandering to
an expanded federal government role, which could serve to
the state legislatures, subject to a check by Congress. In
standardize certain redistricting criteria or elements of the
contrast to population equality and racial gerrymandering
district drawing process across states. Given the historically
claims, the Court also determined that no test that is both
limited role Congress has played in the redistricting
judicially discernible and manageable exists for
process, concerns about federalism may arise in the context
adjudicating partisan gerrymandering claims. Instead of the
of certain congressional efforts related to redistricting.
federal courts, the Court suggested that Congress and the
state legislatures could play a role in regulating partisan
Some bills in the 117th Congress would establish criteria for
gerrymandering.
districts, such as population equality, compactness,
contiguity, or preservation of existing political subdivisions
State Requirements for Congressional
(e.g., H.R. 1, S. 1, H.R. 80, H.R. 3863, H.R. 4307, H.R.
Districts
5746, S. 2093, S. 2670, and S. 2747). Bills have also been
In addition to compliance with federal standards described
introduced that would require states to use independent
above, states often require districts to meet certain other
redistricting commissions (e.g., H.R. 1, S. 1, H.R. 80, H.R.
congressional redistricting criteria, many of which are
100, H.R. 3863, H.R. 4307, S. 2093, and S. 2670) and/or
related to geography. Often, decisionmakers weigh trade-
maintain certain standards of public input and transparency
offs between criteria, and some states specify a priority
regarding the redistricting process (e.g., H.R. 4, H.R. 81,
order in which factors are considered.
and H.R. 7948). Some bills include provisions to prevent
states from redistricting more than once following an
Criteria such as
compactness, required by 31 states, and
apportionment, a practice sometimes referred to as
mid-
contiguity, required by 34 states, relate to a district’s shape.
decade redistricting (e.g., H.R. 1, H.R. 80, H.R. 134, H.R.
A compact district is a geographically consolidated area,
4307, H.R. 5746, S. 1, S. 2093, S. 2670, and S. 2747).
though state laws often do not specify precise measures of
Chamber actions were taken on H.R. 1 (passed the House);
compactness. A district is generally considered contiguous
H.R. 5746 (House agreed to the text as an amendment to a
if one can travel between any two points without crossing
Senate amendment to an unrelated bill; in the Senate,
into another district. Thirty-one states require consideration
cloture was not invoked on the question of agreeing to the
of existing
political subdivisions (e.g., towns, cities, or
House amendment); S. 2093 (cloture not invoked on the
counties). Twenty-one states require preserving
motion to proceed); and S. 2747 (cloture not invoked on the
communities of interest, which are generally groups of
motion to proceed).
people who share a background or characteristics (e.g., a
social, cultural, historical, racial, ethnic, partisan, or
For additional discussion, see CRS Report R45951,
economic identity). Five states require preserving the
Apportionment and Redistricting Process for the U.S.
“core” of an existing district, and two states allow this as a
House of Representatives, by Sarah J. Eckman.
consideration.
L. Paige Whitaker, Legislative Attorney
https://crsreports.congress.gov
Congressional Redistricting: Key Legal and Policy Issues
IF12250
Sarah J. Eckman, Analyst in American National
Government
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