The Supreme Court on Tuesday agreed to decide whether Ohio wrongfully purged eligible voters from the state's registration list.
The justices said they will hear an appeal from state officials defending the process against challengers who say it's illegal.
Civil liberties groups had challenged the state's program for removing thousands of people from voter rolls based on their failure to vote in recent elections. The 6th U.S. Circuit Court of Appeals in Cincinnati ruled last year that the process violates the National Voter Registration Act.