Updated at 3:54 p.m. ET
(CBS/AP) HARRISBURG, Pa. - Pennsylvania's highest court on Tuesday told a lower court judge to stop a tough new law requiring voters to show photo identification from taking effect in this year's presidential election if he finds voters cannot easily get ID cards or if he thinks they will be disenfranchised.
The 4-2 decision by the state Supreme Court sends the case back to a Commonwealth Court judge who initially said the divisive law could go forward. The high court asked the judge, Robert Simpson, for his opinion by Oct. 2.
"The ruling means more drama, next month, with just weeks to go before the election," CBS Radio News senior legal analyst Andrew Cohen said. "The trial judge now has to respond to this and give attorneys for both sides a chance to make new arguments."
If Simpson finds there will be no voter disenfranchisement and that IDs are easily obtained, then the 6-month-old law can stand, the Supreme Court said.
"It's certainly a very positive step in the right direction in that the court recognizes that the state does not make adequate provision for people to get the ID that they would need to vote," said David Gersch, the lead lawyer for the plaintiffs challenging the law's constitutionality. "In addition, there is a practical problem with getting the ID to people in the short time available."
Penda Hair, co-director of the Advancement Project, one of the organizations that challenged the law, praised the court's action as a "step in the right direction."
In the meantime, the Pennsylvania Department of State, which oversees voting and elections, said it will continue telling Pennsylvanians to bring proper identification to the polls "until the judge makes a decision" to grant an injunction stopping the law, spokesman Mathew Keeler told CBS News.
"We believe, as we have all along, that any legal voter who wants to get an ID is able to do so," spokesman Ron Ruman said.
The Department of State had estimated about 1 percent of registered voters -- more than 80,000 people -- did not meet the law's requirements, which is the estimate Simpson accepted in his August decision upholding the law. Around 9,000 voters have obtained a free identification since the spring, Ruman told CBS News.
Pennsylvania is one of 10 states to adopt such identification laws in the past two years in the name of stopping voter fraud. CBS News surveyed all 10 of those states and reports that the number of voter fraud convictions is very rare. In Pennsylvania, for example, there have been no convictions for voter fraud on state or federal charges in the past decade.
A recent study funded by the Knight Foundation and the Carnegie Corporation, which surveyed all 50 states, found that instances of voter fraud across the country are "infinitesimal" - about one instance of voter impersonation fraud for every 15 million registered voters in the United States.
The court's three sitting Republican justices were joined in Tuesday's majority by one of the court's Democrats, Max Baer. The court's two other Democrats dissented.
Part of the problem, the four majority justices noted, is that the state has scrambled to deal with impediments to distributing a photo ID card promised under the law to any registered voter who needs one. The state began issuing new, voting-only ID cards in late August, after Simpson's original ruling.
"Thus, we will return the matter to the Commonwealth Court to make a present assessment of the actual availability of the alternate identification cards on a developed record in light of the experience since the time the cards became available," the justices wrote.
The justices also pointed to Gersch's suggestion during last week's oral arguments that the photo ID requirement can be constitutional if the state has ensured all eligible voters can get the photo IDs they need.
Some of the people who sued over the law had raised the claim that they might be unable to vote because they lacked the necessary documents, such as an official birth record, to get the law's ID card of last resort: A state nondriver photo ID that is subject to strict federal requirements.
In oral arguments Sept. 13 before the Supreme Court, Justice Thomas Saylor pointed out that the state cannot comply with the "letter of the law," which calls for issuing an ID card to registered voters who need it, because the cards still require supplemental identification that a registered voter might not be able to produce.
Two of the lawsuit's plaintiffs whothe law would prevent them from voting have since found ways to comply with it.
Viviette Applewhite, the 93-year-old Philadelphia woman who was the lead plaintiff, got a voting card making her eligible to vote on Election Day by producing her birth certificate -- the same one with her maiden name that previously fell short of the document requirements --- and providing her Social Security number, Advancement Project spokesman Rich Robinson told CBS News in August.
Bea Booker, 93, testified at the original trial that she was too infirmed to travel to a driver's license center to get an ID. But Simpson found Booker could vote by absentee ballot.
"I have voted in every presidential election, and I hope to vote in every one until I die," Booker previously told CBS News.
The Republican-penned ID law passed over the objections of Democrats and ignited a furious debate over voting rights, making it a high-profile issue in the contest for the state's prized 20 electoral votes between President Obama, a Democrat, and Republican nominee Mitt Romney, the former Massachusetts governor.
Republicans, long suspicious of ballot-box stuffing in the Democratic bastion of Philadelphia, say the law would deter election fraud. But Democrats pointed to a blank trail of evidence of such fraud, and charged that Republicans are trying to steal the White House by making it harder for the elderly, disabled, minorities, the poor and college students to vote.
The law among the nation's toughest has inspired protests, warnings of Election Day chaos and voter education drives. It was already a political lightning rod when a top state Republican lawmaker boasted to a GOP dinner in June that the ID requirement "is going to allow Gov. Romney to win the state of Pennsylvania."
The plaintiffs eight registered Democrats, plus the Homeless Advocacy Project, the League of Women Voters of Pennsylvania and the Pennsylvania chapter of the National Association for the Advancement of Colored People had sought to block the law from taking effect in this year's election as part of a wider challenge to its constitutionality.
Republican Gov. Tom Corbett signed the law in March after every single Democratic lawmaker voted against it.
The prior law required identification only for people voting in a polling place for the first time and it allowed nonphoto documents such as a utility bill or bank statement.