The 5–4 vote reinstates an election law provision.
U.S. Supreme Court justices have narrowly voted to approve a request from the Republican National Committee (RNC).
Justices in a 5–4 vote agreed to reinstate a part of Arizona law that requires officials to reject state registration forms from voters who did not provide proof of citizenship.
The restoration is in effect pending the outcome of the case in the U.S. Court of Appeals for the Ninth Circuit.
The ruling affects some 41,000 voters who used state registration forms and did not provide proof of citizenship by providing a birth certificate or another document.
Chief Justice John Roberts and Justices Clarence Thomas, Samuel Alito, Neil Gorsuch, and Brett Kavanaugh voted in favor of reinstating the citizenship provision.
Justices Sonia Sotomayor, Elena Kagan, Amy Coney Barrett, and Ketanji Brown Jackson voted against the request.
Michael Whatley, chairman of the RNC, said on social media that the partial reinstatement was “a seismic win in the fight to stop non-citizens from voting.”
Arizona Senate Republicans added that the ruling “affirmed that voters who register with the state must provide proof of citizenship to cast a ballot in [the state’s] elections moving forward.”
The Arizona Democratic Party and the Democratic National Committee, two of the groups that sued over the laws, did not respond to requests for comment.
The RNC had also asked justices to restore Arizona provisions that require voters to provide their state or country of birth when registering and that require counties to verify that voters on their rolls are citizens and purge the ones who are not. But a majority of justices declined to restore those provisions.
Thomas, Alito, and Gorsuch would have reinstated all of the provisions, but Roberts and Kavanaugh joined with the other four justices to reject that part of the request.
The provisions were previously blocked by a U.S. district court judge, who ruled that they violate federal law and entered an injunction.
Ninth Circuit judges initially stayed the injunction, but other judges on the court later reinstated it, finding that the RNC and other parties had not shown a strong likelihood of succeeding in the case or a high degree of irreparable injury.
That’s because the RNC did not explain how it is being injured by voters’ using state forms not proving citizenship when voters who register with federal forms do not have to provide proof of citizenship, the three-judge appeals court panel said.
The Aug. 1 ruling prompted the appeal to the Supreme Court.
The new ruling came on the same day as the ballot printing deadline for some Arizona counties.