The Justice Department, under the authority granted to them by Section 5 of the Voting Rights Act, rejected a voter ID law from South Carolina, making good on a promise to exercise vigilance on voting rights as we near the 2012 elections.

Per the Voting Rights Act, DoJ must pre-clear changes to election law in nine mostly Southern states, because of past incidents where those states failed to protect the voting rights of minorities. In its ruling, the Justice Department alleged that the voter ID law would make it harder for minorities to cast their ballots, because many lack a current eligible ID card.

The Obama administration said South Carolina’s law didn’t meet the burden under the 1965 Voting Rights Act, which outlawed discriminatory practices preventing blacks from voting. Tens of thousands of minorities in South Carolina might not be able to cast ballots under South Carolina’s law because they don’t have the right photo ID, Assistant Attorney General Thomas Perez said [...]

South Carolina’s new voter ID law requires voters to show poll workers a state-issued driver’s license or several other alternative forms of photo identification.

“The U.S. Department of Justice today blocked implementation of a new law that would require South Carolina voters to present a photo ID in order to vote,” the state Election Commission said in a statement late Friday. “Therefore, ID requirements for voting will not change at this time.’

In a celebrated speech last week, Eric Holder promised vigilance against voter suppression laws that have popped up with increasing regularity around the country since Republicans triumphed in the 2010 elections. This action represents the first salvo.

Kansas, Wisconsin and Tennessee also passed new voter ID laws this year, which the Justice Department doesn’t have the authority to review. South Carolina was the first subject to pre-clearance rules under the Voting Rights Act, and a DoJ review is pending on another voter ID law, in Texas. Voter ID laws have already been ruled constitutional by the Supreme Court in a 2008 case over Indiana’s version. The Justice Department under George W. Bush pre-cleared a voter ID law in Georgia in 2007. The state of Texas has used this as ammunition to try to get the Obama DoJ to pre-clear their new voter ID law.

But it didn’t work in South Carolina’s case, especially after evidence provided by the state’s Department of Motor Vehicles showed almost 240,000 registered voters who had no eligible ID, with the disproportionate amount of those voters being African-American or Hispanic. Thomas Perez of the Civil Rights Division wrote in the ruling, “Minority registered voters were nearly 20 percent more likely to lack DMV-issued ID than white registered voters, and thus to be effectively disenfranchised.” DMV officials in South Carolina contend those numbers were inflated, and that many have moved out of state or were deceased. Based on this new evidence, the state could potentially petition for reconsideration.

But South Carolina officials have indicated that they may appeal the ruling through the judicial process, which would first go to federal district court. Rick Hasen believes this could go to the Supreme Court, and in a troublesome thought, thinks this could be a method to strike down Section 5 of the Voting Rights Act.

I anticipate that South Carolina (and Texas) will take the preclearance decisions to a three judge court in DC, with direct appeal to the U.S. Supreme Court. I further expect that in this litigation, South Carolina (and Texas) will argue, among other arguments, that Section 5 of the Voting Rights Act is unconstitutional—an issue which has been percolating in the lower courts.

It would further not surprise me for South Carolina (and Texas) to seek expedited review of this question in the DC court as well as in the Supreme Court, on grounds that the state wishes to use its new voter i.d. law in the 2012 election. That could cause the constitutional question in this case to leapfrog over the other cases raising this issue, giving the Supreme Court a chance to strike down section 5 of the Voting Rights Act as unconsitutional before the 2012 election.

Because the Supreme Court upheld Indiana’s voter ID law in 2008, it would not surprise me to see them uphold South Carolina’s version. And that could be a means to invalidate Section 5, giving Southern states with a history of racial discrimination in voting the chance to do so again.

So while the Justice Department’s ruling is admirable and necessary, the consequences down the road could be severe. And needless to say, this makes the 2012 Supreme Court session, already laden with decisions on Arizona’s immigration law and the federal health care law, all the more consequential.