The U.S. Supreme Court is set on Monday to hear 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 United States is halfway to the next once-a-decade census, but the Supreme Court is still dealing with lawsuits that grew out of the last one. The justices on Monday are taking up a challenge to Louisiana’s congressional map,