The court ruled that the law does not have a discriminatory purpose.
Under the law, known as R54, voters without an ID can sign an affidavit at a polling location saying they have a "reasonable impediment" to obtaining identification -- such as lacking a car, having a disability or not having an accurate birth certificate. The voter is then allowed to cast a provisional ballot, which must be counted "unless the board has grounds to believe the affidavit is false," according to the law.
South Carolina is one of 16 southern states that require pre-clearance for voting laws under Section 5 of the Voting Rights Act because of a history of racism. The Justice Department refused to pre-clear the state's ID law in December, citing statistics showing that voters without ID are 20 percent more likely to be black, and one-third of registered minority voters do not have a driver's license.
R54 requires voters to show a driver's license or other photo identification, passport, military identification or a voter registration card with a photo on it. Gov. Nikki Haley (R) signed the law in 2011.
(Click here to read the decision in full.)
UPDATE: 2:43 p.m. -- In a statement, South Carolina Attorney General Alan Wilson called the ruling a "major victory" for the state. Gov. Nikki Haley (R) praised the ruling on Facebook: "The Feds keep throwing punches but in South Carolina heels and boxing gloves prevail! This is another win for our state and country!"
Leah Aden, assistant council for the Political Participation Group of the NAACP Legal Defense Fund, which joined the Justice Department in the case, told HuffPost, "Our general response is that it's significant and important that this law would discriminate against voters in the 2012 election." Aden added that she hopes "that the state's efforts at educating voters between now and 2013 go into effect immediately so voters can comply and are not prevented from voting."