Courts have played a crucial role in redistricting over the past few decades, helping to ensure that districts are fair and representative of the people within their boundaries. In particular, the U.S. Supreme Court, as the high court of the United States, has provided various legal principles that reshaped redistricting litigation.
A series of key rulings during the early 1960s established the role of courts in redistricting cases, which Chief Justice Earl Warren later concluded were the most important cases decided during his tenure. While the Supreme Court has nixed the ability to challenge partisan gerrymandering cases in federal court, it has set important precedent in protecting (and sometimes weakening) minority voting rights in racial gerrymandering cases.
In today’s Explainer, we’re breaking down some of the most crucial redistricting cases in our nation’s history.
“One Person, One Vote” Cases
1. Baker v. Carr (1962)
“The complaint’s allegations of a denial of equal protection present a justiciable constitutional cause of action upon which appellants are entitled to a trial and a decision. The right asserted is within the reach of judicial protection under the Fourteenth Amendment.”
The case: Tennessee voters challenged the state’s failure to redraw its state legislative districts for sixty years despite significant population growth. After the district court dismissed the case, the Supreme Court held that legislative apportionment claims brought under the 14th Amendment are justiciable (suitable for courts to decide on).
The significance: This ruling meant that redistricting cases could be litigated in federal courts, opening the door for lawsuits challenging state apportionment schemes.
2. Wesberry v. Sanders (1964)
“[A]s nearly as is practicable, one man’s vote in a congressional election is to be worth as much as another’s.”
The case: Voters residing in Georgia’s 5th Congressional District, which had two to three times as many people as other districts, argued that their vote and its impact was diluted in comparison to other voters who lived in less populous districts. The Supreme Court held that the population disparities between Georgia’s congressional districts violated the U.S. Constitution and its “plain objective of making equal representation for equal numbers of people the fundamental goal for the House of Representatives.”
The significance: The holding that congressional districts must be drawn to have as close to equal populations as possible forced many districts to be redrawn, further cementing the principle of one person, one vote.
3. Reynolds v. Sims (1964)
“The overriding objective [of drawing districts] must be substantial equality of population among the various districts, so that the vote of any citizen is approximately equal in weight to that of any other citizen in the State.”
The case: Alabama voters challenged the state legislature maps, which hadn’t been redrawn since 1901 despite uneven population growth. The Supreme Court ruled that the 14th Amendment requires that state legislative districts have roughly equal populations if possible. It also held that both houses of bicameral (two chamber) legislatures have to be apportioned based on population.
The significance: State legislative maps had to be redrawn following this ruling since most states had one chamber of their legislature that was not apportioned based on population and was therefore unconstitutional after this case.
Partisan Gerrymandering Cases
4. Rucho v. Common Cause (2019)
“To hold that legislators cannot take partisan interests into account when drawing district lines would essentially countermand the Framers’ decision to entrust districting to political entities.”
The case: North Carolina voters challenged the state’s 2016 congressional map as being a partisan gerrymander in favor of Republicans. The district court struck down the map, finding that the plaintiffs had standing to sue and that the map was a partisan gerrymander. Upon appeal to the Supreme Court, the case was consolidated with similar cases challenging state maps for partisan gerrymandering. The Court held that partisan gerrymandering claims are not justiciable (suitable for courts to decide on) because they present a political question that is beyond the reach of federal courts.
The significance: After decades of punting the issue, the Supreme Court’s ruling put an end to partisan gerrymandering cases in federal courts. This means that, during future rounds of redistricting, partisan gerrymandering will be fair game unless a state’s constitution prohibits it or Congress passes a law that bans the practice, like the For the People Act.
Racial Gerrymandering Cases
In case you missed it, Shelby County v. Holder (2013) is another important case we wrote about here.
5. Thornburg v. Gingles (1986)
“The critical question in a § 2 claim is whether the use of a contested electoral practice or structure results in members of a protected group having less opportunity than other members of the electorate to participate in the political process and to elect representatives of their choice.”
The case: Black voters in North Carolina challenged the state legislature maps, arguing that they were purposefully drawn to dilute the voting power of Black individuals. During the course of the case, Section 2 of the Voting Rights Act was amended to make clear that an election law that has a discriminatory effect, as opposed to only a discriminatory intent, could also violate Section 2. The Supreme Court unanimously held that North Carolina’s state legislative districts violated Section 2 because they were drawn to prevent a minority group from electing its preferred candidates.
The significance: The Supreme Court established three criteria for proving a pattern of racial vote dilution: 1) the minority group in question must be “sufficiently large and geographically compact” to elect a candidate of its choice; 2) the minority group must be politically cohesive (meaning they typically vote in a similar manner); and 3) the majority group must be politically cohesive enough to defeat the minority group’s preferred candidate(s). The Court also held that voters do not need to show discriminatory causation or intent to prove vote dilution claims.
6. Shaw v. Reno (1993)
“Redistricting legislation that is so bizarre on its face that it is ‘unexplainable on grounds other than race,’ … demands the same close scrutiny that we give other state laws that classify citizens by race.”
The case: North Carolina voters challenged the state’s congressional maps, arguing that they constituted an unconstitutional racial gerrymander by purposefully concentrating Black voters to create two majority-Black districts. Focusing on the “bizarre” shape of the districts, the Supreme Court held that race cannot be a predominant factor in drawing districts and courts must closely review whether, if race is determined to be the leading factor, its use is narrowly tailored and serves a compelling governmental interest.
The significance: Shaw established the legal principle that racial considerations in redistricting are subject to strict scrutiny by courts.
7. Miller v. Johnson (1995)
“The … burden is to show, either through circumstantial evidence of a district’s shape and demographics or more direct evidence going to legislative purpose, that race was the predominant factor motivating the legislature’s decision to place a significant number of voters within or without a particular district.”
The case: White voters challenged the constitutionality of Georgia’s redistricting plan, specifically a majority-Black district drawn to satisfy preclearance requirements under Section 5 of the Voting Rights Act. The Supreme Court, applying Shaw’s strict scrutiny standard, struck down the district as an unconstitutional racial gerrymander that was not tailored to any compelling state interest.
The significance: This ruling affirmed Shaw, but went one step further by analyzing legislative intent to determine whether racial motivations were the predominant factors in drawing districts. In other words, the shape of a district is not the only criteria to consider when analyzing racial gerrymandering claims.
8. Alabama Legislative Black Caucus v. Alabama (2015)
“It is not about whether a legislature believes that the need for equal population takes ultimate priority. Rather, it is … whether the legislature ‘placed’ race ‘above traditional districting considerations.”
The case: The Alabama Legislative Black Caucus and Alabama Democratic Conference challenged the state’s 2012 maps, arguing that they were racial gerrymanders that violated the 14th Amendment. The Supreme Court held that courts must review racial gerrymandering claims on a district-by-district basis. It also reversed the District Court’s decision, finding that it had erred in holding that the need to create districts equal in population meant that maps were not racially discriminatory.
The significance: In holding that the constitutional requirement of one person, one vote is not a key factor in determining whether states impermissibly used race to draw districts, the Supreme Court protected minority voters in future litigation by establishing strict legal principles by which lower courts must review districts. This case set the stage for future racial gerrymander challenges, such as Bethune-Hill v. Virginia State Board of Elections (2019).
9. Cooper v. Harris (2017)
“A State may not use race as the predominant factor in drawing district lines unless it has a compelling reason.”
The case: North Carolina voters challenged the state’s 1st and 12th Congressional Districts as unconstitutional racial gerrymanders. The Supreme Court held that the General Assembly had unlawfully used race to draw congressional districts in violation of the 14th Amendment. The Court rejected the state’s arguments that race had been used as a predominant factor to satisfy Section 5 of the Voting Rights Act, finding that this reasoning did not withstand strict scrutiny.
The significance: This ruling was a win for racial gerrymandering claims, as North Carolina was ordered to redraw its congressional maps. However, the state relied on partisan considerations when redrawing, which then led to Rucho v. Common Cause.