MADISON, Wis., Dec. 15 (UPI) -- A new Wisconsin law requiring voters to show government-issued photo ID violates the U.S. Constitution, the American Civil Liberties Union says in a lawsuit.
The suit, filed in federal court in Milwaukee, claims the law infringes on some citizens' right to vote and to receive equal treatment under the law, the Milwaukee Journal Sentinel reported.
Republican Gov. Scott Walker, GOP lawmakers and numerous state officials named in the lawsuit predicted the law would be upheld.
The legal challenge to the Wisconsin law came as U.S. Attorney General Eric Holder pledged Tuesday to enforce civil rights protections as states around the country pass voter ID laws.
The Wisconsin suit was filed by the national ACLU and its Wisconsin affiliate, along with the National Law Center on Homelessness & Poverty, on behalf of a group of senior citizens, minorities and homeless residents.
"This lawsuit is the opening act in what will be a long struggle to undo the damage done to the right to vote by strict photo ID laws and other voter-suppression measures," said Jon Sherman, an attorney with the ACLU Voting Rights Project.
Opponents say the photo ID law makes it harder, and costly, for some to exercise their right to vote. Supporters say it will discourage voter fraud and instill more public confidence in elections.
Cullen Werwie, a spokesman for Walker, pointed out 15 other states enacted laws requiring voters to present photo ID and that the practice has been upheld by the U.S. Supreme Court.
"The common-sense election reforms signed into law earlier this year by Governor Walker are constitutional," Werwie said in an e-mail. "Requiring photo identification to vote helps ensure the integrity of our elections -- we already require it to get a library card, cold medicine, and public assistance."