A federal appeals court will hear oral arguments in September in an appeal that could affect the voting rights of thousands of voters in Kansas, Georgia and Alabama in upcoming elections.

The U.S. Court of Appeals for the District of Columbia on Thursday set a Sept. 8 hearing date in the case of a U.S. election official who without public notice required documentary proof of citizenship on a national voter registration form used by residents of the three states.

The court a day earlier had set deadlines for July and early August for the parties to submit written filings.

A judge in Washington, D.C., sided last month against voting rights advocates who seek a temporary order overturning the move by Brian Newby, executive director of the U.S. Election Assistance Commission.