The US Supreme Court Wednesday took up the US voting rights law, a cornerstone of efforts to guard against a resurgence of racial discrimination in American states with a segregationist past.
At issue is the 1965 law's Section 5, which requires nine mainly southern states and local governments in seven other states to obtain Justice Department approval for any changes in their electoral codes.
The nearly half-century-old law, which bars all racial discrimination at the polls, is opposed by some states as outmoded, but a number of civil rights organizations argue it is still needed.
"Though there have been improvements, this past election has shown that the law is not outdated and sadly continues to be extremely necessary," said Caroline Fredrickson, head of the American Constitution Society.
Texas, for one, has faced repeated Justice Department challenges to its election redistricting laws as well as a state law requiring voters to present photo identification.
In both instances, a federal appeals court in Washington ruled that the provisions were "discriminatory," and now Texas is waiting to argue its position before the Supreme Court.
Several states are challenging the law's Section 5, but the Supreme Court is considering just one complaint brought by Shelby county in Alabama.
It comes immediately after the re-election of the United States' first black president, Barack Obama -- something critics point to as evidence that the law is unnecessary.
"The violence, intimidation, and subterfuge that led Congress to pass Section 5 and this court to uphold it no longer remains," Shelby County's brief says.
The county points out that 83 percent of its 200,000 inhabitants are white, a demographic mix that it contends puts it above suspicion of racial discrimination.
It maintains that Section 5 should be simply thrown out, complaining that the Obama administration is enforcing it with greater zealousness than in the past.
More than 20 religious, civic and human rights organizations have joined in calling on the top court to confirm Section 5's constitutionality as "the heart of the voting rights act," as the NAACP, the country's most prominent black civil rights organization, put it.
The law "has played a key role in protecting our democracy and ensuring the vitality of the right of minorities to vote and fully participate in the political process", said NAACP president Sherrilyn Ifill.
Defenders of the law rested their arguments on the Constitution's 15th amendment, which bans racial discrimination at the polls.
The nine-member court, which has a conservative majority, left the law alone the last time they reviewed it in 2009, but strongly urged the Congress to reform it on grounds that "things have changed in the South."
It also expressed concern that it puts states' rights at the mercy of the federal government, despite protections afforded by the 10th amendment to the constitution.
The federal government for its part calls on the justices to consider that the Congress in 2006 extended the law for another 30 years.
This time, however, the top court could prove deaf to those appeals because the Congress failed to heed its warning.