Democrats cried foul after a judge ordered a purge of nearly a quarter-million voters in response to a lawsuit filed by a right-wing group on Friday.

The Wisconsin Elections Commission sent a letter to nearly 234,000 voters in October warning that they needed to re-register in order to remain on the voter rolls because authorities believe they had relocated. “If you move, even to an apartment in the same building, you must update your voter record by reregistering,” the commission warned at the time.

The letter did not set a deadline for voters to re-register and the commission later said that voters would have until 2021 to do so. But the conservative Wisconsin Institute for Law and Liberty filed a lawsuit arguing that the commission is required to remove those voters within 30 days of sending the letter.

Ozaukee County Circuit Judge Paul Malloy, who was appointed by Republican Gov. Scott McCallum in 2002, agreed with the complaint on Friday, ruling that the commission must remove everyone on the list who does not re-register within 30 days,