( CNN ) -- How much has the South changed ? That 's the question at the heart of one of the most important cases the Supreme Court will take up this year . The case weighs the fate of one of the most important laws in American history : the Voting Rights Act of 1965 . A century after the Civil War , Congress created that law to give African Americans the right to vote , not just on paper , but in fact . The key provision was Section 5 , which decreed that jurisdictions with histories of discrimination , mostly in the South , had to get Justice Department approval before they changed any aspect of their voting rules , right down to the location of polling places . There is little doubt that , in the years immediately after 1965 , the Voting Rights Act achieved a revolution in voting rights for African-Americans in the South . In subsequent years , Congress has reauthorized the law several times , most recently in 2006 . Increasingly , covered jurisdictions have found the process of submitting their changes to the Justice Department , which is known as `` pre-clearance , '' as a demeaning anachronism , and Shelby County , Alabama , went to court to argue that the Voting Rights Act was unconstitutional . The court will hear the case , Shelby County v. Holder , early next year . The Obama administration strongly supports the act , but the president 's election -- and re-election -- may be among the best arguments against the law . There is little doubt that African-Americans suffered pervasive discrimination in the 1960s , especially at the polls . But now we have a black president . Does n't that prove that African-Americans have reached at least rough equality in the electoral realm ? Not necessarily . When reauthorizing the law , Congress compiled a record of thousands of pages documenting the legacy of discrimination that lingers in the covered jurisdictions . The government asserts that the justices should defer to Congress in deciding whether the problem of voting rights is solved . Still , the Obama administration has to deal with a very important likely adversary in this case : Chief Justice John Roberts . The court heard a similar challenge to the Voting Rights Act in 2009 , and the court sidestepped the core issue , resolving the case on procedural grounds . But there was little doubt , in Roberts ' questions at oral argument or in his opinion , that he believes , constitutionally speaking , times have changed . The chief is unlikely to look for a procedural way out of controversy for a second time . The controversy over voter suppression in the 2012 elections might have a paradoxical effect on the future of the law . Democrats argued that the efforts to impose Voter ID requirements and the like amounted to discrimination against African-Americans and thus could be seen as justification for preserving the Voting Rights Act . But several of the acts of alleged voter suppression took place in states -- like Pennsylvania and Ohio -- that are not covered by Section 5 of the act . That may help the plaintiff 's core argument : Times have changed in the South . In any event , it 's likely to be a close vote . What happens if the law is overturned ? The answer may be : not much . The South may not need the act anymore to protect the voting rights of minorities . If that 's true , that would prove the plaintiffs ' main argument in this case . The opinions expressed in this commentary are solely those of Jeffrey Toobin .
# ##s : The Voting Rights Act secured voting rights for blacks in the South . Alabama county takes it to Supreme Court , saying act is unconstitutional . Toobin : Is it still necessary ? Does it still exist in the South ? Toobin : Ruling will be close , with Chief Justice Roberts likely to oppose U.S. Constitution .