A divided Supreme Court ruled Monday that Ohio’s law for removing voters from registration rolls does not violate federal laws to protect people who simply choose not to vote, a decision that voter rights advocates say could lead to disenfranchisement across the country.

A 5-4 opinion, written by Justice Samuel A. Alito Jr. and joined by the court’s conservative wing, could pave the way for other states to use a similar system for keeping their voter rolls up to date.

The decision, which split the court along familiar ideological lines, comes amid a broader battle over laws about voter identification and registration. President Donald Trump and Republicans often raise questions about voter fraud, while civil rights groups say voter purges and other election laws that alter voting periods or registration are a way to suppress voters.

Alito wrote that an estimated 24 million voter registrations in the United States are either invalid or significantly inaccurate, encompassing about 1 in 8 voters. Ohio uses the failure to vote for two years as a rough way of identifying voters who may have moved, and then sends a card asking them to verify they live at the same address.

Ohio voters who do not return the card and fail to vote in any election for four more years are presumed to have moved and are removed from the rolls, Alito wrote. The U.S. Court of Appeals blocked the state law, ruling that it violates a 1993 national voter registration law that says voters can’t be removed from voting simply because they didn’t vote.

The Supreme Court reversed the appeals court decision, with a majority concluding that Congress and Ohio had included the process of sending back such a card in federal laws. The state’s card process means that removal is not based solely on someone’s record of not voting, the majority concluded.

“It was [Congress’] judgment that a reasonable person with an interest in voting is not likely to ignore notice of this sort,” Alito wrote. “We have no authority to second-guess Congress or to decide whether Ohio’s Supplemental Process is the ideal method for keeping its voting rolls up to date.”

Justice Stephen G. Breyer, in a dissent joined by the court’s liberal wing, wrote that an unreturned card is irrelevant to the decision to remove a voter from the rolls because it “adds nothing to the State’s understanding of whether the voter has moved or not.”

Breyer pointed out that about 1 million Ohio registered voters — or 13 percent of the state’s voting population — did not send back their cards, and “the streets of Ohio’s cities are not filled with moving vans.”

The state’s card procedure “will sometimes help provide confirmation of what the initial identification procedure is supposed to accomplish: finding registrants who have probably moved,” Breyer wrote. “But more often than not, the State fails to receive anything back from the registrant, and the fact that the State hears nothing from the registrant essentially proves nothing at all.”

Six states have similar laws, according to the Brennan Center for Justice. The other five are Georgia, Oklahoma, Oregon, Pennsylvania and West Virginia. Ohio is the only one that starts the removal process after failing to vote in only one election, the center said.

House Minority Leader Nancy Pelosi called the decision dangerous and “a grave step backward in our nation’s progress to advance a future in which every person can enjoy their full, equal right to be heard at the ballot box.”

“This wrongly-decided decision paves the way to mass disenfranchisement in Ohio and around the country, disproportionately impacting communities of color and working families who already face suppression of their voices,” the California Democrat said in a news release.

The liberal-leaning Center for American Progress said the ruling was a green light for other states to manipulate voter rolls.

“The Supreme Court has just given a stamp of approval to voter suppression,” Liz Kennedy, the group’s senior director of democracy and government reform, said in a news release. “Ohio’s system of purging voters that choose not to participate in some elections unfairly silences hundreds of thousands of voters in the state, especially people of color and the homeless.”