WASHINGTON (CNN) -- Mary-Jo Criswell wants to vote in the November elections but is not sure if she will be able to, because of one barrier: She does not have government-issued photo identification.
Voters would have to show a photo ID under an Indiana law being reviewed by the Supreme Court.
An Indiana state requirement, which opponents say could lock Criswell and potentially thousands of others out of the electoral process, will come before the U.S. Supreme Court in oral arguments Wednesday.
At issue is whether state laws designed to stem voter fraud end up discriminating against large groups of minority and poor Americans, who might lack proper identification.
The experience of Criswell, a 71-year-old Democrat, was cited as part of a lawsuit before the justices. It says that voter identification laws discourage and intimidate large groups of Americans from going to the polls.
It is perhaps the biggest voter rights case taken up by the court since the 2000 dispute over Florida's ballots. The current issue raises important constitutional questions but also involves race and hot-button partisan politics.
The appeals involve an Indiana law, passed by the Republican-controlled legislature in 2005, requiring that a voter present a photo ID when casting a ballot in person. Previously, citizens needed only to sign a poll book to vote.
State and federal courts around the country have issued conflicting rulings on voter ID laws. Missouri's law was found unconstitutional, but similar ones in Georgia, Arizona and Michigan were found to be proper.
Officials in Indiana justify their law, which a federal appeals court upheld.
"The real question is, does it disenfranchise anyone?" asked Indiana Secretary of State Todd Rokita. "After six elections in the state of Indiana, the answer has been no. ... That's why the opponents to this keep losing in court. They have not been able to produce the person that was truly disenfranchised yet."
Civil rights activists and the state Democratic Party complain Indiana's law is the most restrictive in the nation, an effort by Republican leaders to reduce turnout among minority voters, many of whom might vote Democratic.
The National Association for the Advancement of Colored People and the American Civil Liberties Union are among the groups that filed suit. They said there was no evidence of recent voter fraud in Indiana that justified the new law.
Donna Brazile, who chairs the Democratic National Committee's Voting RIghts Institute, offers a simple analogy for the Indiana requirement, calling it "a modern-day version of the poll tax."
"The voter ID scam is a suppression tactic used by many people to undermine the right to vote in this country," said Brazile, who managed Al Gore's 2000 presidential run and is also a CNN political contributor.
Liberal activists said laws such as this one help Republicans by keeping many voters away who might be inclined to vote Democratic, an allegation state and national leaders strongly deny.
"I think it pits kind of two philosophical camps," said Edward Lazarus, a Supreme Court legal analyst and author of a book on the justices. "Those who think a certain amount of partisan maneuvering, with respect to voting rules, is something that is just part of the American way ... and others who are going to view the right to vote as something extraordinarily sacrosanct, where equal access to the ballot -- for everyone from the poorest person to the richest, in the absence of some real evidence of fraud -- is something that should be protected."
Criswell's circumstances were cited when the case was heard in the lower courts. She had always used a private bank-issued card with her photo when voting. The onetime precinct committeewoman had difficulty rebuilding an identity trail and still lacks a photo ID acceptable under the new law.
Indiana officials argue the Bureau of Motor Vehicles is required to provide free photo ID cards to anyone who asks and that voter turnout has increased 2 percent since the law took effect. But Rokita concedes the state has never presented a case of "voter impersonation," which the law purportedly was designed to fight.
Indiana argues the state has the responsibility to clamp down on the problem before it happens, to prevent any election from being tainted after the fact.
The Republican National Committee has made the voter fraud issue a prominent feature of public outreach. A large section of the party's Web site is devoted to allegations of ballot tampering around the country.
In a sign of the political stakes involved, at least 35 political and advocacy groups have filed amicus briefs supporting one side or the other.
State laws on voter identification vary widely, with Indiana's and Georgia's considered the most restrictive. Nearly all states require a photo identification when people first register to vote.
The Supreme Court already has heard two election-related appeals this term. One involves Washington state's open primary system, and the other is a dispute over the selection of state judges in New York.
A ruling in the Indiana case is expected by late June -- in time, perhaps, for states to revise their laws for the November elections, if required. E-mail to a friend