The federal panel on Wednesday found that the law was not discriminatory because of the safeguards in it, but would require more time to put those protections against discrimination in place.
The move follows a string of recent voter law decisions. In Pennsylvania, a judge blocked the state from enforcing its voter ID law next month, saying voters would have trouble getting IDs before elections. A federal appeals court forced Ohio to reinstate three early voting days leading up elections. And in Mississippi last week, state officials announced they could not enforce photo ID requirements for this year's elections after the Justice Department asked for more details on the law. Courts also have blocked voter ID laws in Texas and Wisconsin.
In several states, though, photo ID laws are in effect—such as in Indiana, Georgia and Tennessee.
Such laws became priority issues in mostly Republican legislatures and for governors after the 2008 elections. Opponents have described them as responses to the record turnouts of minorities and other Democratic-leaning constituencies that helped put Barack Obama, the first African-American president, in the White House.
Debate over the laws intensified in part because of the tight presidential race between Obama and Republican challenger Mitt Romney. Supporters have pitched these laws as necessary to deter voter fraud, even if very few cases of voter impersonation have been found, and to build public confidence in elections.
South Carolina officials portrayed Wednesday's decision as vindication for the state.
"Would I have loved for it to happen in 2012? Absolutely. But do not lose sight that this was a powerful fight that we really had to scratch and kick to get done," said South Carolina Gov. Nikki Haley, a Republican. She signed the law last December.
The judges said in their unanimous decision there was no discriminatory intent behind the law, ruling that it would not diminish African-Americans' voting rights because people who face a "reasonable impediment" to getting an acceptable photo ID can still vote if they sign an affidavit. Without that provision, the law may have run into problems under Section 5 of the Voting Rights Act, which bars denying or abridging the right to vote based on race or color, according to the decision.
South Carolina is one of 16 states, mostly in the South, where election laws are subject to Justice Department approval under the federal Voting Rights Act because of a history of discrimination. South Carolina's law was the first to be refused federal OK in nearly 20 years, which led state officials to challenge that decision in federal court.
The judges also noted the new law allows voters to show a driver's license, ID issued by the Department of Motor Vehicles, a newly-created voter registration card with a photo, a passport or military ID. That expands the list of acceptable ID under existing law, which requires a driver's license, state ID or a voter registration card to vote, the judges said.
The judges declined to let the law take effect immediately, "given the short time left before the 2012 elections and given the numerous steps necessary to properly implement the law."
South Carolina voters who lack the proper photo ID are disproportionately African-American, so proper and smooth functioning of the law "would be vital to avoid unlawfully racially discriminatory effects," according to the decision, written by Judge Brett M. Kavanaugh of the U.S. Court of Appeals for the District of Columbia Circuit. "There is too much of a risk to African-American voters for us to roll the dice," he said.
The judges said the law must be practiced with broad exception for people without photo ID who claim a "reasonable impediment."
"We are fully aware, moreover, that what looks good on paper may fall apart in practice. We expect and anticipate that South Carolina state, county and local officials will endeavor to prevent such slippage," the decision states.
Dena Iverson, a Justice Department spokeswoman, said the administration is pleased the law won't be in effect for this election and in future elections "the Attorney General intends to monitor its implementation closely to ensure compliance with the court's order."
The other judges in the case were Colleen Kollar-Kotelly and John D. Bates of the U.S. District Court in Washington.
Kollar-Kotelly was appointed by President Bill Clinton. Bates and Kavanaugh were appointed by President George W. Bush.
The case number is 2012-203.
Associated Press writer Pete Yost in Washington and Jeffrey Collins in Columbia, S.C. contributed to this report.
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