Updated

The Supreme Court appeared ready Wednesday to uphold the nation's strictest requirement that voters show photo identification before casting a ballot.

The justices are faced with a partisan dispute that echoes the bitterly divided decision that sealed the 2000 presidential election for George W. Bush. Now, as then, the court seemed divided along ideological lines.

Wednesday's arguments were over a challenge to an Indiana law, passed in 2005, that is backed by Republicans as a prudent way to deter voter fraud. Democrats and civil rights groups oppose the law as unconstitutional and call it a thinly veiled effort to discourage elderly, poor and minority voters — those most likely to lack proper ID and who tend to vote for Democrats.

But Justice Anthony Kennedy, often a key vote on the court, did not sound persuaded that the challengers had made their case.

"You want us to invalidate a statute on the ground that it's a minor inconvenience to a small percentage of voters?" Kennedy said near the end of the lively session. Kennedy did, however, voice concern over some aspects of obtaining an ID, including the difficulty the poor have in getting the birth certificates that are needed to get photo ID.

More than 20 states require some form of identification at the polls. Courts have upheld voter ID laws in Arizona, Georgia and Michigan, but struck down Missouri's. The Indiana case should be decided by late June, in time for the November elections.

The justices could use the case to instruct courts on how to weigh claims of voter fraud versus those of disenfranchisement.

Paul Smith, representing the challengers, told the justices that there is no evidence of in-person voter fraud in Indiana. He said the law is a subtle way "to skew the outcome on election days."

Indiana Solicitor General Thomas Fisher said the vast majority of Indiana voters easily comply with the law. "You're talking about an infinitesimal portion of the electorate that could be burdened," Fisher said under sharp questioning from Justice David Souter.

Justice Samuel Alito, who appeared more sympathetic to Indiana's case, posed the question that troubled several justices.

With little evidence of fraud or of voters who have been kept from voting, Alito said, "The problem I have is, where do you draw the line? There is nothing to quantify the extent of the problem or the extent of the burden."

Chief Justice John Roberts, who grew up in Indiana, and Justice Antonin Scalia indicated strong support for the state law. Justice Clarence Thomas said nothing, but most often votes with his conservative colleagues.

When Smith said poor voters lacking ID have to visit the county courthouse within 10 days of an election and sign a sworn statement there to have their ballot counted, Roberts asked, "How far away is the furthest county seat? ... County seats aren't very far for people in Indiana."

The court's four liberal justices were more critical of the state.

Justice Ruth Bader Ginsburg focused her questions on the difficulties for indigent voters who lack IDs. Why, she asked, can't the state allow those voters to sign a sworn statement on Election Day, which would eliminate the second trip to the county courthouse?

Told Indiana wants to avoid congestion at the polls, Ginsburg said the state wants to have it both ways because it argues relatively few people are affected by the law. "If there are so few of them, I don't understand why they should be put to the burden," Ginsburg said.

Souter and Justice John Paul Stevens both pressed Fisher on the state's problems with voter registration rolls, which Fisher acknowledged are among the nation's worst in terms of retaining the names of the dead and those who have moved. Indianans are not required to show photo ID to register.

"Is it the policy to have it tougher to vote than to register?" Stevens said. "That doesn't make sense to me."

Justice Stephen Breyer wondered why the state doesn't just give photo IDs to newly registered voters who otherwise lack them. "That ... would satisfy your anti-fraud interest much better than the way you have chosen," Breyer told Fisher.

The consolidated cases are Crawford v. Marion County Election Board, 07-21, and Indiana Democratic Party v. Rokita, 07-25.