Florida Gov. Ron DeSantis (R) signed legislation that will require people with felony convictions to pay all of their outstanding fines and fees before they can vote again, a move that critics say significantly undermines a constitutional amendment to expand voting rights in the state.

The amendment, which voters approved overwhelmingly in November, repealed Florida’s lifetime voting ban for people with felony convictions. The measure allows those convicted of a felony, except for murder or sexual offenses, to vote once they “complete all terms of their sentence including parole or probation.” The change was estimated to affect up to 1.4 million people. It got rid of a policy rooted in the racism of the Jim Crow South.

In January, the amendment officially went into effect and Floridians with felony convictions have been registering to vote ever since.

But Republican lawmakers, who control both chambers of the state legislature, argued that completing a criminal sentence should include repaying all financial obligations ordered as part of that sentence. The legislature approved the new requirement in May.

In a letter addressed to Florida Secretary of State Laurel Lee on Friday, DeSantis suggested the legislation was a step toward addressing flaws he saw in the voting rights amendment.

“Curiously, the amendment did not address the restoration of other civil rights, such as the right to hold public office and to serve on a jury,” the governor wrote, adding that he would consider doing so for nonviolent offenders.

DeSantis went on to say he thought it was a “mistake” that the amendment restored voting rights to those convicted of some violence offenses, including attempted murder and kidnapping.

“As I consider options for restoration of civil rights to non-violent offenders, my administration will execute this legislation to ensure the restoration of voting rights,” he wrote.

The law that DeSantis signed does allow people to petition a judge to waive their outstanding fines and fees. But state legislators eliminated a different provision that would have allowed someone to vote if a judge converted that debt to a civil lien ― something frequently done when someone finishes a sentence but can’t pay the related debt.

Critics say the law is akin to a poll tax. After DeSantis signed the bill, civil rights groups filed two federal lawsuits almost immediately on behalf of people with felony convictions ― some of whom have registered to vote. They said the restrictions on voting violated the 1st, 14th, 15th and 24th amendments of the U.S. Constitution, which prohibits poll taxes. One suit also says the measure violates a clause of the Constitution that prohibits states from imposing laws that punish people retroactively.

“If not enjoined, the law will have a massive disenfranchising effect, and result in sustained, and likely permanent, disenfranchisement for individuals without means,” lawyers wrote in one suit. “It creates two classes of returning citizens: those who are wealthy enough to vote and those who cannot afford to. This disenfranchisement will be borne disproportionately by low-income individuals and racial minorities, due to longstanding and well-documented racial gaps in poverty and employment.”

The civil rights groups representing the plaintiffs are the American Civil Liberties Union, the NAACP Legal Defense Fund, the Brennan Center for Justice and the Campaign Legal Center.

Republicans passed the bill over strong objections from supporters of the amendment, who argued that requiring repayment would drastically weaken the impact of the constitutional change. They say many people convicted of felonies accumulate debts they can never afford to repay and therefore will never be able to vote in the state. One estimate, which relied on 2007 data, found that requiring repayment of fines and fees could lower the number of people effectively eligible for restored voting rights from 1.4 million to 840,000.

The Florida Rights Restoration Coalition, the main group that pushed to pass the constitutional amendment, said in a statement it would work to help people be able to vote, despite the new restrictions. The group announced a donation-based fund to assist people with repaying fines and fees so they can vote.

“We are committed to operating under the law to register every one of the estimated 840,000 immediately eligible returning citizens in Florida. For the remaining 500,000, we will utilize the provisions of the legislation and generosity of our allies and extended FRRC family to provide relief for those facing financial barriers in completing their sentences,” said Desmond Meade, the group’s executive director.

Antonia Blumberg contributed to this report.

This article has been updated with the announcement of a fund to help people pay fines and fees to be able to vote.