Washington ? The Supreme Court on Monday reached a compromise on the Voting Rights Act that allowed it to sidestep the question of whether a key provision of the landmark civil rights legislation remains constitutional at a time when the nation’s racial politics have changed forever.

Instead, the court decided that all political subdivisions covered by the provision have the right to prove that they do not discriminate, and thus would not need to have federal authorities approve election law changes.

That provision, called Section 5, is the heart of the act, and applies to Virginia, Alaska, Alabama, Arizona, Georgia, Louisiana, Mississippi, South Carolina and Texas and parts of seven other states.

Civil rights activists had braced themselves for the conservative majority on the court to find Section 5 unconstitutional. But the court refused to do that on an 8-1 vote with only Justice Clarence Thomas, the court’s only black member, going that far. He said that “punishment for long past sins is not a legitimate basis” for imposing the act’s toughest restrictions on mostly Southern states.

Chief Justice John Roberts Jr., who at oral arguments had been sharply critical in his questioning of government lawyers who defended Congress’s 2006 decision to extend the Voting Rights Act of 1965 for another 25 years, said the court did not need to settle the larger issue.

“That constitutional question has attracted ardent briefs from dozens of interested parties, but the importance of the question does not justify our rushing to decide it,” Roberts wrote.

The approach seemed to follow Roberts’ stated goal of deciding cases as narrowly as possible and avoiding what probably would have been another divisive ruling for the court on an important constitutional issue.

Roberts made clear he had questions about the sweep of Congress’s extension of the act: “Things have changed in the South,” Roberts wrote. “Voter turnout and registration rates now approach parity. Blatantly discriminatory evasions of federal decrees are rare. And minority candidates hold office at unprecedented levels.”

Civil rights groups applauded the decision. “It’s fair to say this case was brought to tear the heart out of the Voting Rights Act, and today that effort failed,” said Debo Adegbile, lead attorney for the NAACP Legal Defense and Educational Fund.