WASHINGTON -

The U.S. Justice department has filed a brief in a federal case involving Wisconsin's voter ID law.

The law requiring Wisconsin voters to show an ID at the polls was struck down by District Court Judge Lynn Adelman in April of 2014 and is currently under appeal.

In its filing to the 7th Circuit Court of Appeals, Justice Department attorneys argue that requiring voters to show ID at the polls unfairly impacts minority voters.

DOJ has also intervened in a similar case in Ohio where a law limits when voters can cast an early ballot.

The Wisconsin Supreme Court is expected to issue a ruling early Thursday morning in two cases concerning the voter ID law.