The U.S. Supreme Court grappled on Monday with a bid by Louisiana officials and civil rights groups to preserve an electoral map that raised the number of Black-majority congressional districts in the state and prompted a challenge by non-Black voters.

The Supreme Court grappled Monday with a years-old, messy legal battle over Louisiana’s congressional districts during an oral argument in which several of the court’s conservatives questioned whether the state had violated the Constitution because of its focus on race.