The Supreme Court on Wednesday ruled that Louisiana’s congressional map, which was drawn to add a second majority-Black district, “is an unconstitutional racial gerrymander.”

The 6-3 ruling in Louisiana v. Callais guts a key part of the Voting Rights Act, potentially affecting congressional district lines ahead of the 2026 midterms.

Justice Elena Kagan, who penned the dissent, called the Callais ruling the “latest chapter in the majority’s now-completed demolition of the Voting Rights Act.” She wrote that under the court’s new parameters, states can “systematically dilute minority citizens’ voting power.”

The court’s majority ruled in favor of Republicans in the state who argued that the state’s use of race when creating its 2024 congressional map was unconstitutional.

Section 2 of the Voting Rights Act of 1965 has been interpreted to allow states to use redistricting on racial lines in order to ensure the voting power of minorities is not diluted.

The majority opinion from Justice Samuel Alito shows that states would have an uphill battle if they tried to redraw districts on racial lines in the future.

“Allowing race to play any part in government decisionmaking represents a departure from the constitutional rule that applies in almost every other context,” Alito wrote, adding that Section 2 of the law “could not justify the State’s use of race-based redistricting here.”

The case spilled over from the Supreme Court’s past term, when it deliberated whether Louisiana’s congressional map relied too much on race. On the final day of its last term, the court took the rare step of kicking the case to the current term for new arguments. It broadened the scope of the question to address whether “the State’s intentional creation of a second majority-minority congressional district violates the Fourteenth or Fifteenth Amendments to the U.S. Constitution,” opening the door to a potential overhaul of the congressional map.

Louisiana, where the case originated, had already decided to use the state’s current map for the upcoming midterms, even as Louisiana Democratic and Republican lawmakers professed a desire last summer for the Supreme Court to make a final decision on the matter. But The New York Times estimated that about a dozen Democratic House seats could be in danger in other Southern states, including Tennessee and Georgia.

On Friday, Republican Mississippi Gov. Tate Reeves announced his plans to call a special session to allow the state Legislature to redraw the maps following the ruling.

Louisiana v. Callais initially centered around a challenge from 12 voters who identified as “non-African American” and argued that the state’s 2024 congressional map too heavily relied on race. The map added a second majority-Black district in the state, won by Democratic Rep. Cleo Fields in November 2024.

In October’s oral arguments, conservative justices asked questions of the defense that suggested that they would consider ruling against the Voting Rights Act.

Justice Neil Gorsuch, for example, asked a lawyer from the NAACP Legal Defense Fund if it is “acceptable” under the Voting Rights Act for “a court to intentionally discriminate in a remedial map on the basis of race?”

The final ruling stopped short of declaring Section 2 of the Voting Rights Act unconstitutional.

But Justice Clarence Thomas, who was part of the majority, indicated that he is willing to entertain further challenges to the law.

“As I explained more than 30 years ago, I would go further and hold that Section 2 of the Voting Rights Act does not regulate districting at all,” Thomas wrote in a concurring opinion.