Missouri Supreme Court judges raised many questions Wednesday as they considered the constitutionality of a new state law requiring people to show photo identification to vote.

A lower judge threw out the law last month, saying it infringes on the fundamental right to vote.

On Wednesday, judges honed in on the cost to obtain a birth certificate — $15 in Missouri — one of the documents needed to get a state identification card or driver's license.

"They all cost money," said Judge Richard Teitelman.

Supporters of the law argue it's needed to combat fraud and increase confidence that people's legitimate votes are being diluted and that more than 95 percent of Missourians already have a license or state ID card.

"Does it make a difference that it's only 3 percent (lacking an ID)?" asked retired Supreme Court Judge Charles Blackmar, who was sitting in for Judge William Ray Price Jr. Courts have established that "you should not have to pay for the right to vote."

Opponents say people impersonating someone else at the polls is rare and the photo ID requirement is a burden that especially harms the poor, elderly and disabled, who may be less likely to already have a driver's license.

The Supreme Court did not indicate when it would rule. The requirement was supposed to take effect for the Nov. 7 election.

If the court reversed the ruling and reinstated the ID requirement, people lacking the proper identification this fall could cast a provisional ballot. In future elections, only the elderly, disabled and those with religious objections to carrying a photo ID could vote without one, and then just by a provisional ballot.