WASHINGTON, May 22 (Reuters) - The U.S. Supreme Court on Monday ruled that Republicans in North Carolina unlawfully took race into consideration when drawing congressional district boundaries, concentrating black voters in a bid to diminish their overall political clout.
The justices upheld a lower court's February 2016 ruling that threw out two majority-black U.S. House of Representatives districts because Republican lawmakers improperly used race as a factor when redrawing the legislative map after the 2010 census. The court was unanimous on upholding the ruling on one of the districts and split 5-3 on the other, with three conservatives dissenting.
The decision came in one of a number of lawsuits accusing Republicans of taking steps at the state level to disenfranchise black and other minority voters who tend to back Democratic candidates.
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Critics accused Republicans of cramming black voters into what the NAACP civil rights group called "apartheid voting districts" to diminish their voting power and make surrounding districts more white and more likely to support Republicans. Both districts are held by the Democrats. Of North Carolina's 13 representatives in the U.S. House, 10 are Republican.
Race can be considered in redrawing boundaries of voting districts only in certain instances, such as when states are seeking to comply with the federal Voting Rights Act. That law protects minority voters and was enacted to address a history of racial discrimination in voting, especially in Southern states.
The Supreme Court has never said legislative districts cannot be mapped based on plainly partisan aims like maximizing one party's election chances. North Carolina Republicans said one of the two districts was drawn on purely partisan grounds to benefit Republicans at the expense of Democrats, and the other was drawn to comply with the demands of the Voting Rights Act.
Justice Neil Gorsuch, who had not yet joined the court when arguments in the case were heard, did not participate in the ruling.