MADISON, Wis. -

A conservative-leaning Wisconsin Supreme Court justice says she has problems with the state's voter photo identification law.

Lawsuits challenging the Republican-authored law argue that it creates an undue burden on people to obtain state-issued IDs and paying for copies of supporting documents such as birth certificates. The Wisconsin Department of Justice is defending the law.

The Supreme Court took both cases after a Dane County judge struck down the law after challenges from the NAACP and League of Women Voters. Gov. Scott Walker signed the law almost three years ago, but the legal challenges mean poll workers still aren’t asking for IDs.

Tuesday, the justices heard the cases separately. The League of Women Voters argued the case creates an additional unfair requirement to vote, and the NAACP argued that it creates an undue burden to vote.

“If we look at the facts presented in this case, the state presented no evidence to why this law was needed to protect electoral process in Wisconsin,” NAACP attorney Richard Saks said.

Attorney for the League of Women Voters Les Pines argued that the lawmakers didn’t have the power under the state constitution to create a new requirement to vote.

“The legislation has now said, ‘You have to prove your identity.’ That’s an additional qualification to vote that is not in the constitution,” Pines said.

Justice Pat Roggensack, a member of the court's four-justice conservative majority, told DOJ attorney Clayton Kawski she's concerned someone might have to pay for copies of documents needed to get an ID. She says that equates to paying the state to vote.

Kawski said some people will face a burden but 90 percent of Wisconsin residents already have an ID.

For the voter ID law to be actively enforced, it would have to survive these state Supreme Court rulings, which are expected this summer, plus two more challenges in federal court.