Recent gerrymandering cases have redrawn the rules for challenging district maps in two directions at once. Federal courts no longer hear partisan gerrymandering claims, but they still police racial vote dilution under the Voting Rights Act, and state courts remain free to apply their own constitutions. The result: where you file, and under which theory, now matters as much as whether the map is unfair.
Rucho v. Common Cause Closed the Federal Door to Partisan Claims
The 2019 decision in Rucho v. Common Cause is where the current era begins. In a 5-4 ruling by Chief Justice Roberts, the Supreme Court held that partisan gerrymandering claims are “political questions beyond the reach of the federal courts.”1Supreme Court of the United States. Rucho v. Common Cause The consolidated cases involved a North Carolina map drawn to favor Republicans and a Maryland map drawn to favor Democrats.
The majority said the Constitution does not guarantee proportional representation and federal judges have no workable standard for deciding “how much partisan dominance is too much.”1Supreme Court of the United States. Rucho v. Common Cause After Rucho, federal courts handle only racial gerrymandering, under the Equal Protection Clause or the Voting Rights Act. A map drawn for naked partisan advantage, without crossing a racial line, is now a problem for state courts or no one.
Moore v. Harper Kept State Courts in the Game
Four years later, Moore v. Harper tested whether state courts could continue reviewing redistricting at all. After North Carolina’s supreme court struck down a congressional map under the state constitution, Republican legislators argued that the federal Elections Clause gives state legislatures exclusive authority over federal election rules, free from any oversight by state courts or governors. That argument, known as the Independent State Legislature theory, would have gutted the main remaining check on partisan maps.
The Supreme Court rejected it 6-3. Chief Justice Roberts wrote that state legislatures are not “wholly independent bodies” and remain “bound by the constraints imposed by the state constitutions.”2Oyez. Moore v. Harper Judicial review of legislative action, the Court said, has been settled since Marbury v. Madison, and the Elections Clause creates no exception.3Supreme Court of the United States. Moore v. Harper State courts can continue to evaluate congressional maps against state constitutions, which is the principal path left for partisan challenges after Rucho.
Allen v. Milligan Preserved Section 2 of the Voting Rights Act
In 2023, Allen v. Milligan confirmed that Section 2 of the Voting Rights Act still forces states to draw additional majority-minority districts in the right circumstances. Alabama’s post-2020 congressional map had only one majority-Black district even though Black residents are roughly 27 percent of the state’s population. Plaintiffs argued the map diluted Black voting strength in violation of Section 2, which prohibits any voting practice that reduces the right to vote on account of race.4Office of the Law Revision Counsel. 52 U.S. Code 10301 – Denial or Abridgement of Right to Vote on Account of Race or Color
The Court applied the three-part test from Thornburg v. Gingles (1986). A plaintiff must show:
- The minority group is large enough and geographically compact enough to form a majority in a reasonably drawn district.
- The minority group votes cohesively as a bloc.
- White voters vote as a bloc in a way that usually defeats the minority group’s preferred candidates.5Justia. Thornburg v. Gingles
Plaintiffs cleared all three. The Supreme Court affirmed the finding that Alabama’s map likely violated Section 2 and refused the state’s invitation to rework decades of precedent.6Supreme Court of the United States. Allen v. Milligan Alabama had to redraw its lines so that two districts gave Black voters a realistic chance to elect their preferred candidates. The ruling targets two familiar techniques: packing minority voters into one district so their influence is wasted on lopsided wins, and cracking them across many districts so they cannot win anywhere.
Louisiana v. Callais Set the Ceiling on Race-Conscious Maps
Milligan showed when Section 2 requires a majority-minority district. The 2026 decision in Louisiana v. Callais showed what happens when a state draws one and the Section 2 case for it was never actually made.
After the 2020 Census, Louisiana enacted a congressional map with a single majority-Black district. A federal judge in Robinson v. Ardoin found it likely violated Section 2. The legislature responded by passing a new map that added a second majority-Black district. Non-Black voters then sued, arguing the state had subordinated every other redistricting principle to race.
In April 2026, the Supreme Court affirmed that the new map was an unconstitutional racial gerrymander. The key reasoning: the Robinson plaintiffs had not actually satisfied the Gingles preconditions, so Section 2 did not compel the second majority-minority district. Without a valid Section 2 obligation, the state had no compelling interest to justify race-based line drawing, and the map failed strict scrutiny.7Supreme Court of the United States. Louisiana v. Callais
Mapmakers are now in a tighter box. Fail to create a majority-minority district when Section 2 requires one, and face a VRA lawsuit. Create one when Section 2 does not require it, and face an Equal Protection challenge. Threading that needle requires serious demographic and legal analysis before lines are drawn, not after.
Alexander v. South Carolina Raised the Bar for Proving Racial Intent
In 2024, Alexander v. South Carolina State Conference of the NAACP made racial gerrymandering claims substantially harder to win. South Carolina’s legislature redrew Congressional District 1 after the 2020 Census, moving roughly 30,000 Black voters out of the district and into neighboring ones. Challengers said race drove the decision. The state said the lines were drawn purely for partisan reasons.
The Supreme Court sided with the state. To prove racial gerrymandering, a plaintiff must show that race was the “predominant factor” in the legislature’s decisions, overriding race-neutral principles like compactness and keeping communities together.8Supreme Court of the United States. Alexander v. South Carolina State Conference of the NAACP The challengers offered no direct evidence that race drove the process, their circumstantial evidence was thin, and they failed to produce an alternative map showing the legislature could have hit its partisan goals while keeping more racial balance.9Oyez. Alexander v. South Carolina State Conference of the NAACP
Race and party affiliation are strongly correlated in much of the country, so a map drawn for party advantage can look nearly identical to one drawn with racial intent. Alexander tells lower courts to give legislatures the benefit of the doubt in that overlap. A challenger who cannot separate race from party, and who cannot show a concrete alternative map that would have achieved the same political goals, is likely to lose.
State Court Rulings Are Now the Main Venue for Partisan Claims
Because Rucho closed federal courts to partisan challenges and Moore v. Harper kept state courts open, state-level litigation is where partisan maps now get tested. Several state supreme courts have struck down maps using provisions with no federal equivalent.
In Wisconsin, the state supreme court invalidated the legislature’s assembly and senate maps in Clarke v. Wisconsin Elections Commission in December 2023, finding they violated the state constitution’s contiguity requirement. New maps were signed into law in February 2024. In New York, the state’s highest court ruled in Hoffmann v. Independent Redistricting Commission that the commission had to reconvene and complete its constitutional duty rather than defaulting to the legislature.10Justia. Matter of Hoffmann v New York State Ind. Redistricting Commn.
Other states have used different hooks. Ohio’s supreme court struck down legislative maps under state constitutional partisan-fairness rules that require maps to reflect statewide voter preferences. Alaska’s supreme court held that intentional partisan gerrymandering violates the state’s equal protection clause. A Maryland trial court struck down a congressional map as an “extreme outlier” that subordinated constitutional criteria to political considerations. The common thread is state constitutional language about free elections, equal protection, or partisan fairness that goes beyond anything in the federal Constitution. Where that language exists, courts have used it.
The caveat: not every state constitution supplies those protections, and some state courts have declined to treat partisan gerrymandering as justiciable at all. The viability of a partisan claim depends entirely on your state.
Timing Can Defeat a Winning Claim
Even a successful challenge may not reach voters in time. Under the Purcell principle, from Purcell v. Gonzalez (2006), courts generally avoid changing election rules in the period just before an election because last-minute shifts confuse voters and administrators. There is no fixed day count. Courts weigh the disruption of an injunction against the harm of letting a flawed map stand.
That calculus shapes every redistricting case. A ruling that arrives weeks before a primary may still change the map, or may be deferred to the next cycle. Callais was decided in April 2026 with a Louisiana primary scheduled for May, which forced urgent requests to expedite finalization. For anyone considering a challenge, the election calendar is part of the strategy from day one.
What This Means for a Challenge Today
The current rules sort out this way. Racial vote dilution claims still belong in federal court under Section 2, and Milligan confirms they can succeed when the Gingles preconditions are met.6Supreme Court of the United States. Allen v. Milligan Race-conscious maps drawn without that Section 2 foundation are vulnerable to Equal Protection challenges.7Supreme Court of the United States. Louisiana v. Callais Racial gerrymandering claims face a high bar: predominance, direct evidence where possible, and an alternative map that disentangles race from party.8Supreme Court of the United States. Alexander v. South Carolina State Conference of the NAACP Partisan gerrymandering claims live in state court and only in states whose constitutions give courts something to enforce.3Supreme Court of the United States. Moore v. Harper
For a voter who thinks a district map is unfair, the first question is not whether the map is bad but what kind of bad it is, and which court can hear that complaint. Matching the claim to the venue, and filing early enough that Purcell does not swallow the remedy, is now most of the work.