Human rights groups on Friday sued Florida over a law that in effect denies more than a million ex-convicts the right to vote in the 2020 presidential election in the key swing state.
Governor Rick DeSantis, a Republican, had earlier Friday signed into law the bill, which was approved by the state legislature on May 3.
The American Civil Liberties Union, the largest human rights group in the US, along with the NAACP, the largest advocacy group for African-Americans, and New York University Law School filed suit against the new law.
"Over a million Floridians were supposed to reclaim their place in the democratic process, but some politicians clearly feel threatened by greater voter participation," said Julie Ebenstein, a lawyer working with an ACLU voter rights project.
In November last year, Florida voters taking part in a referendum known as Amendment 4 agreed to restore the voting rights of more than one million former convicts, except those who had served time for murder or sex crimes.
It was a vestige of racist laws dating back 150 years to the end of the US civil war.
But the Republican-dominated state legislature created another bill, the one signed Friday, that curbed the process.
The new law states that people recovering their right to vote must first settle any outstanding debts they have with the courts. This can be in the thousands of dollars and beyond many people's means.
"They cannot legally affix a price tag to someone's right to vote," said Ebenstein.
Critics argue that Florida's Republican lawmakers want to prevent 1.4 million ex-cons who have recovered their right to vote -- most are black or Hispanic, and poor -- from registering to vote in the 2020 presidential election.
The issue is highly sensitive in a state where elections tend to be decided by a very narrow margin. And Florida also tends to play a key role in deciding the ultimate winner.
"Our research shows that the people who have registered to vote under Amendment 4 are disproportionately black and low-income," said Myrna Perez, director of the Brennan Center?s Voting Rights and Elections Program at NYU.
"There can be no mistaking the racial and class implications of this regressive new legislation," said Perez.