In one sense, the Supreme Court’s surprise ruling striking down Alabama’s 2022 congressional maps maintains the legal status quo. By 5-4, the justices rejected the state’s attempt to restrict the ability of the Voting Rights Act to block gerrymanders that suppress the power of minority voters.

But that dramatically understates the impact of the case, titled Allen v. Milligan, election law experts say.

Though it simply reaffirms existing law, the ruling — authored by Chief Justice John Roberts, who was joined by Justices Elena Kagan, Sonia Sotomayor, and Ketanji Brown Jackson, and, in part, by Justice Brett Kavanaugh — is likely to provide a major boost to lawsuits challenging racial gerrymanders from Georgia to Washington state.

That could help Democrats in the battle for control of the U.S. House and state legislatures in the 2024 election. A top political analyst cited the ruling in shifting five House seats in the party’s direction, four of the five moving to toss-ups.

And, at a time when civil rights groups are warning that the political power of racial minorities is under threat in some areas, the ruling could lead to the creation of more U.S. House districts across the country where black and brown voters hold a majority.

Richard Pildes, a prominent election law professor at New York University, predicted that broader changes in the redistricting field, combined with the impact of the ruling, will lead to more election maps being blocked under the Voting Rights Act.

“In light of this decision,” Pildes said via email, “the combination of (1) technological advances that make it easier to search out new (Voting Rights Act) districts that comply with a state’s redistricting criteria, (2) a now heavily-resourced private bar fully engaged in this project, and (3) an infusion of new social science experts into this area means that we are going to see more successful Section 2 actions, both for Congress and other representative bodies.”

Alabama court rulings

Section 2 of the Voting Rights Act prohibits any voting rules or laws that deny or curtail the right to vote based on race. It has mostly, though not entirely, been used to challenge election maps that make it harder for racial minorities to elect their preferred candidates.

In the Alabama case, a federal district court had ruled last year that Alabama’s congressional maps violated Section 2. Though black voters make up 26.8 percent of Alabama’s population, only one congressional district in the maps approved by the Alabama Legislature in 2021 was majority-minority.

Soon after the district court blocked the map, the U.S. Supreme Court stayed that opinion, meaning that Alabama’s 2022 elections took place using the gerrymandered map.

On Thursday, the justices upheld the district court’s ruling.

Alabama had argued, among other things, that it wasn’t required to draw the additional black-majority district because doing so would have conflicted with other legitimate goals of the map-drawing process, including keeping voters from the Gulf Coast region together, and keeping districts the same as they were in previous decades.

In an argument that reached even further, Alabama claimed that deliberately drawing maps that take race into account so that racial minorities can elect their preferred candidates constitutes illegal racial discrimination.

Had the court accepted those arguments, it would have made it much harder to bring Section 2 claims in the future. Instead, the justices reaffirmed the multi-pronged test that the courts have used for decades to decide whether a majority-minority district must be drawn.

“The Court declines to remake its Section 2 jurisprudence in line with Alabama’s ‘race-neutral benchmark’ theory,” Roberts wrote. Ruling for Alabama, he added, “would require abandoning four decades of the Court’s Section 2 precedents.”

Redistricting lawsuits in other states

The ruling could give a boost to more than two dozen other ongoing efforts to challenge political maps as racial gerrymanders. According to a database of redistricting lawsuits maintained by Democracy Docket, which is run by the Democratic election lawyer Marc Elias, there are 31 ongoing redistricting lawsuits that make claims under Section 2.

The Alabama case, according to Democracy Docket’s analysis, will have a “reverberating and largely positive impact” on the cases.

In a similar case in Louisiana, a district court had blocked the state’s congressional map as a racial gerrymander, but the case was put on hold pending a ruling in the Alabama case.

Though black voters make up a third of Louisiana’s population, the map contained only one majority black district. As in Alabama, the 2022 elections were held using the challenged map.

Congressional maps drawn by Georgia and Texas also have been challenged under Section 2.

And the Harvard Law professor Nicholas Stephanopoulos, a prominent redistricting expert, said in an email that Thursday’s ruling could make it harder for Republicans to wipe out a congressional district where Black voters have a chance to elect their preferred candidate in eastern North Carolina, which is set to conduct redistricting later this year.

In a response to the Alabama ruling, the Cook Political Report changed its ratings for two U.S. House districts in Alabama and two in Louisiana from “Solid Republican” to “Tossup.” It also changed the North Carolina district from “Tossup” to “Lean Democratic.”

It isn’t just the fight for the U.S. House that could be affected. Eight states — Alabama, Arkansas, Georgia, Louisiana, Michigan, Mississippi, North Dakota and Washington — have seen their state legislative maps challenged under Section 2.

The result could well be to increase the number of non-white lawmakers in state legislatures, and perhaps even to boost Democrats’ chances of winning or maintaining control of some chambers.

The potential jolt to minority political power comes as a departure from the court’s direction in recent years.

In 2013, Roberts authored a ruling, in Shelby County v. Holder, that neutered a different plank of the Voting Rights Act, known as Section 5. In Shelby, he found that, when it comes to racial discrimination in voting in the South, “things have changed dramatically” since the 1960s, and as a result, Section 5 was no longer needed.