Gerrymandering

Gerrymandering, in U.S. politics, is the practice of drawing the boundaries of electoral districts in a way that gives one political party an advantage over its rivals (political or partisan gerrymandering) or that dilutes the voting power of members of racial or ethnic minority groups (racial gerrymandering). The term is derived from the name of Gov. Elbridge Gerry of Massachusetts, whose administration enacted a law in 1812 defining new state senatorial districts. The law consolidated the Federalist Party vote in a few districts and thus gave disproportionate representation to Democratic-Republicans. The outline of one of these districts was thought to resemble a salamander. A satirical cartoon by Elkanah Tisdale that appeared in the Boston Gazette graphically transformed the districts into a fabulous animal, “The Gerry-mander,” fixing the term in the popular imagination.

See also What is gerrymandering?

Early rulings against gerrymandering

A basic objection to gerrymandering of any kind is that it tends to violate two tenets of electoral apportionment—the compactness of constituencies and their equality of size. The constitutional significance of the latter principle was set forth in a U.S. Supreme Court ruling issued in 1962, Baker v. Carr, in which the Court held that the failure of the legislature of Tennessee to reapportion state legislative districts to take into account significant changes in district populations had effectively reduced the weight of votes cast in more populous districts, amounting to a violation of the equal protection clause of the Fourteenth Amendment. In 1963, in Gray v. Sanders, the Court first articulated the principle of “one person, one vote” in striking down Georgia’s county-based system for counting votes in Democratic primary elections for the office of U.S. senator. One year later, in Wesberry v. Sanders, the Court declared that congressional electoral districts must be drawn in such a way that, “as nearly as is practicable, one man’s vote in a congressional election is to be worth as much as another’s.” And in the same year, the Court affirmed, in Reynolds v. Sims, that “the Equal Protection Clause requires that the seats in both houses of a bicameral state legislature must be apportioned on a population basis.”

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Racial gerrymandering

Regarding cases of gerrymandering based on race, the Supreme Court has held (in Thornburg v. Gingles, 1986) that such practices are incompatible with Section 2 of the 1965 Voting Rights Act (as amended in 1982), which generally prohibits voting standards or practices whose effect is that members of racial minority groups “have less opportunity than other members of the electorate to…elect representatives of their choice.” In Shaw v. Reno (1993), the Court ruled that electoral districts whose boundaries cannot be explained except on the basis of race can be challenged as potential violations of the equal protection clause, and in Miller v. Johnson (1995) it held that the equal protection clause also prohibits the use of race as the “predominant factor” in drawing electoral-district boundaries.

Attempted adjudication of partisan gerrymandering

Until the 1980s, disputes regarding partisan gerrymandering were generally considered nonjusticiable (not decidable by courts) on the presumption that they presented “political questions” that are properly decided by the legislative or the executive branch. In Davis v. Bandemer (1986), however, a plurality of the Supreme Court held that partisan gerrymanders could be found unconstitutional under the equal protection clause if the resulting electoral system “is arranged in a manner that will consistently degrade a voter’s or a group of voters’ influence in the political process as a whole.” A majority of the Court also agreed that the instance of gerrymandering under consideration did not display any of the “identifying characteristics of a nonjusticiable political question” that had been laid out in Baker v. Carr, including, as the Baker Court had put it, “a lack of judicially discoverable and manageable standards for resolving it.” Although the majority in Bandemer could not agree on what standards should be used to adjudicate challenges to partisan gerrymanders, it refused to accept that none existed, declaring on that basis that “we decline to hold that such claims are never justiciable.”

In 2004, in Vieth v. Jubelirer, a plurality of the Court pointedly embraced what the Bandemer Court had declined to hold, on the grounds that “no judicially discernible and manageable standards for adjudicating partisan gerrymandering claims have emerged” since the Bandemer decision. Although siding with the plurality in rejecting the challenge to the gerrymander in question, Justice Anthony Kennedy asserted that it had not been long enough since the Bandemer decision to conclude that no suitable standards could ever emerge (“by the timeline of the law 18 years is rather a short period”). Pointing to the rapid development and routine use of computer-assisted districting, he argued that such technologies “may produce new methods of analysis that…would facilitate court efforts to identify and remedy the burdens” imposed by partisan gerrymanders, “with judicial intervention limited by the derived standards.”

Just such a standard was proposed in Gill v. Whitford (2018), a challenge to a Wisconsin redistricting law enacted by the Republican-controlled state legislature following the 2010 decennial census. In that case, the plaintiffs argued that the discriminatory effects of the redistricting plan could be measured objectively by comparing the “efficiency” of votes cast for Republican or Democratic candidates in state legislative elections since 2012. Partisan gerrymandering characteristically results in a greater number of “wasted” votes for the disfavored party (that is, votes for a losing candidate or votes for a winning candidate in excess of the number needed to win), a discrepancy that can be represented as an “efficiency gap” between the parties when the difference between wasted votes is divided by the total number of votes cast. The plaintiffs argued that efficiency gaps of 7 percent or greater were legally significant because they were more likely than smaller gaps to persist through the standard 10-year life of a redistricting plan. The Court’s ruling, however, did not consider whether the efficiency gap amounted to the “judicially discernible and manageable” standard it had been waiting for. Instead, the justices held unanimously (9–0) that the plaintiffs lacked standing to sue, and the case was remanded (7–2) to the district court for further argument.

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Following Kennedy’s retirement in 2018, the Supreme Court once again took up the issue of the justiciability of partisan gerrymandering claims in Rucho v. Common Cause (2019). There the Court’s conservative majority, over the bitter objections of its more liberal members, declared (5–4) that “partisan gerrymandering claims present political questions beyond the reach of the federal courts.”

Expansion of partisan gerrymandering

In the wake of the decennial census of 2020, the dominant parties in many states took advantage of the Rucho ruling to openly gerrymander congressional districts to their own advantage. In 2025, at the request of Republican President Donald Trump, the state of Texas departed from convention by holding a special redistricting session well before the next decennial census. The acknowledged purpose of the partisan gerrymandering was to ensure the addition of five more Republican congressional representatives in the midterm elections of 2026, thus preventing Democrats from overcoming the Republicans’ narrow majority in the House of Representatives. Trump also urged other Republican-controlled states to conduct similar gerrymanders. In response, California’s Democratic governor Gavin Newsom announced that his state would conduct its own redistricting to prevent Republicans from unjustly retaining their House majority. A few other Democratic governors, accusing Republicans of undermining American democracy, also indicated their willingness to facilitate partisan gerrymandering in their states.

After a federal district court issued a preliminary injunction preventing Texas from using its 2025 map in the midterm elections (on the ground that the new map was based on racial gerrymandering), Texas filed an emergency appeal with the Supreme Court, asking that it stay the lower court’s order. On December 4, 2025, the Court granted the state’s request. In a parallel decision issued on February 4, 2026, the Court denied an emergency appeal by California Republicans asking that it enjoin a lower court’s refusal to issue a preliminary injunction preventing California from using its new 2025 map in the midterm elections. Eventually seven other states (Alabama, Florida, Louisiana, North Carolina, Ohio, Tennessee, and Utah) also redrew their maps.

Later attempts at partisan gerrymandering

On April 22, 2026, Virginia voters approved a House map that would give Democrats an additional four seats. In the following month, however, the Virginia plan was struck down by the state’s supreme court, which held that the procedure under which the map had been approved by voters was in violation of the state’s constitution. Soon afterward, the Virginia attorney general and other state officials submitted an emergency request to the U.S. Supreme Court, asking that it overturn the Virginia court’s ruling. On May 15, the Court officially declined the state’s request. Earlier in the same week, the Court overturned a lower court’s ruling preventing Alabama from redrawing a court-ordered map before the 2026 midterm elections. And on September 8 the Court declined to intervene following the Missouri Supreme Court’s decision preventing the state from using its newly redrawn district map in its November midterm elections. A federal district court then ordered the state to use the new map, and the Supreme Court paused that order pending a decision by the Eighth Circuit Court of Appeals. The appeals court favored the new map in its decision on September 21 but asked the district court to wait while the Supreme Court considered the case. The Court then declined to permit Missouri to use the new map in the 2026 midterm elections.

Despite the successful political gerrymandering conducted by Republican states in support of Trump’s goal of preserving the party’s control of Congress, Republicans lost control of both chambers in the midterm elections of 2026. The elected Democratic majorities in the House of Representatives and the U.S. Senate were significantly greater than those held by Republicans during the first half of Trump’s second term.

Judicial weakening of the Voting Rights Act

On April 29, 2026, the U.S. Supreme Court issued a landmark ruling on the Voting Rights Act , Louisiana v. Callais, finding that the creation of two Black-majority districts in 2024 had violated Section 2 because it purposefully reduced the voting power of white citizens. (In 2023 a lower federal court had found that the existence of only one Black district following the national census of 2020 had violated Section 2 because it effectively reduced the voting power of Black citizens.) The Court’s majority in Callais held in general that redistricting violates Section 2 only if it is undertaken for the purpose of limiting voting power on the basis of race, and not if such limitations are merely a consequence of redistricting. In the wake of the Supreme Court’s decision, Louisiana’s Republican governor delayed the state’s planned May primary election by two months to give the legislature time to create a new body of congressional districts. Soon afterward, the Court overturned a lower court’s order preventing Alabama from reinstating a district map it had created in 2023, which included only one Black-majority district.