While a number of states have passed voter ID laws, only South Carolina and Texas are subject to Section 5 of the Voting Rights Act, which requires certain states with a history of discrimination to have changes to their voting laws pre-cleared by officials in DOJ's Civil Rights Division.
Progressive and civil rights leaders have been pushing DOJ to probe voter ID laws in other states under Section 2 of the Voting Rights Act, which prohibits voting laws which discriminate on the basis of race across the country. But as TPM previously reported, they're unlikely to pursue such cases because it's tough to prove discrimination takes place until after an election takes place when the law is enacted.
In South Carolina, an evaluation by the Associated Press found that the voter ID law appeared "to be hitting black precincts in the state the hardest."
Outside of the federal government, the American Civil Liberties Union has sued Wisconsin (which isn't covered by Section 5) over their voter ID law, maintaining it "imposes a severe and undue burden on the fundamental right to vote under the Equal Protection Clause of the Fourteenth Amendment of the United States Constitution; violates the Twenty-Fourth and Fourteenth Amendments to the United States Constitution as an unconstitutional poll tax; and violates the Equal Protection Clause of the Fourteenth Amendment in arbitrarily refusing to accept certain identification documents."
Attorney General Eric Holder, in his address on voting rights earlier this month, said that in-person voting fraud -- the type of fraud voter ID laws would prevent -- is "uncommon" and said that "making voter registration easier is simply not likely, by itself, to make our elections more susceptible to fraud."