The ACLU (American Civil Liberties Union) filed a lawsuit on Monday challenging New Hampshire’s new voter ID law that requires proof of U.S. citizenship to register to vote and photo identification at the polls.

The lawsuit, filed by the ACLU of New Hampshire on behalf of the Coalition for Open Democracy, the League of Women Voters of New Hampshire, the Forward Foundation and five voters, aims to block the state law claiming that the law imposes some of the most restrictive voting measures in the country and threatens to disenfranchise thousands of eligible voters.

The lawsuit was submitted to the U.S. District Court in Concord just weeks after Republican Governor Chris Sununu signed the bill, which is set to take effect following the November elections. The legal action names New Hampshire Attorney General John Formella and Secretary of State David Scanlan as defendants, and the suit argues that such laws are unconstitutional.

Laws like this that “create unconstitutional roadblocks to voting and which could stop thousands of eligible voters from participating in an election, have no place in our state,” Henry Klementowicz, deputy legal director at the ACLU of New Hampshire, said in a statement.

Currently, New Hampshire voters without photo identification can sign an affidavit affirming their identity and are required to provide documentation within seven days. However, the new law eliminates these exceptions and mandates citizenship proof, such as a passport or birth certificate, at the time of voter registration.

Newsweek reached out to ACLU of New Hampshire and Sununu’s office via email on Monday evening for comment.

Liz Tentarelli, president of the League of Women Voters New Hampshire, condemned the law, stating that it “creates confusion, raises doubts for voters, and leaves them feeling hampered by the process.”

“Instead of creating unnecessary barriers to voters, we need our elected officials to advance meaningful legislation that ensures New Hampshire voters can make their voices heard,” Tentarelli added.

The lawsuit seeks to block the law’s enforcement, saying federal courts have weighed in on the matter before.

The legal action follows a similar case in Kansas, where a law mandating proof of citizenship for state and federal elections was struck down in 2018 for violating the U.S. Constitution and the National Voter Registration Act.

Despite the Kansas ruling, the U.S. Supreme Court in August 2024 allowed some parts of a law requiring proof of citizenship to be enforced in Arizona as the legal fight continues in lower courts.

According to The Associated Press, the New Hampshire Attorney General’s office acknowledged the ACLU lawsuit but did not provide further comment, stating: “We will review the complaint and respond as appropriate.”

Sununu, a vocal supporter of the law, defended the legislation as a step toward preserving the integrity of the state’s election process, claiming it would enhance trust in future elections.

“We have a proud tradition and proven track record of condition elections that are trusted and true,” Sununu said when he signed the bill on September 12. “Looking forward to the next decade or two, this legislation will instill even more integrity and trust in the voting process.”

Meanwhile, Republican efforts at the federal level continue to push for similar measures, with the proposed SAVE Act, a nationwide proof-of-citizenship mandate, also under discussion.

This article includes reporting from The Associated Press.