Maine gun rights advocates filed a federal lawsuit Wednesday in Bangor seeking to overturn the state’s new three-day waiting period for firearm purchases.

The plaintiffs, including a Republican lawmaker from Guilford who owns a store that sells guns, say the waiting period is unnecessary and unconstitutional.

“(The law) does not purport to be tethered to the time it takes to conduct a background check, or to any other investigatory efforts into whether someone is disqualified from exercising Second Amendment rights,” the lawsuit says. “To the contrary, it forces law-abiding citizens to wait 72 hours to acquire a firearm even if they pass the requisite background check in a matter of minutes, which most people do.”

The law is one of several passed last session in response to the October 2023 mass shooting in Lewiston in which a gunman killed 18 people and wounded 13 others.

Two prominent gun rights groups in Maine – the Sportsman’s Alliance of Maine and the Gun Owners of Maine – vowed to challenge the law shortly after it was passed. In August, the groups announced that their legal challenge would be funded by the National Shooting Sports Foundation.

“Everyone at the State House was warned that we had concerns with this,” SAM Executive Director David Trahan said in an interview. “Really, all we’re doing is following through on what everyone at the State House should have known was coming.”

The plaintiffs are Rep. James White and his business, J. White Gunsmithing, as well as Andrea Beckworth, East Coast School of Safety, Adam Hendsbee, A&G Shooting, Thomas Cole, and TLC Gunsmithing and Armory.

They are represented locally by attorney Josh Tardy, of Bangor, with help from Clement & Murphy, a national law firm that has deep experience arguing cases in front of the U.S. Supreme Court, including the New York Rifle and Pistol Association v. Bruen case, which has made it more difficult to enact gun safety legislation.

The suit was filed against Maine Attorney General Aaron Frey in U.S. District Court in Bangor.

“We look forward to defending this important public safety law,” Frey said in a written statement. “Waiting periods have been upheld across the country as a reasonable, limited regulation that does not infringe on Second Amendment rights.”

The lawsuit comes as gun safety advocates are collecting signatures for a citizen initiative to adopt an additional gun safety measure that failed to pass last year. That effort aims to create an extreme risk protection order program, or red flag law, that would allow family members and police to petition a court to restrict firearm access of someone deemed to be a danger to themselves or others.

Maine has a similar law, but it does not allow family members to petition a court. Instead, police are required to take someone into protective custody and have them undergo a mental health evaluation before a court petition can be filed.

Nacole Palmer, executive director of the Gun Safety Coalition of Maine, which is leading the citizens initiative, said she’s confident that Maine’s waiting period law will withstand the challenge and help save lives, noting that waiting periods have broad support from mental health professionals and citizens. She said 90% of Maine’s gun deaths are from suicides, which a waiting period can help prevent.

“Seventy-two-hour waiting periods have been challenged in many states, and courts have consistently upheld them as constitutional in states across the nation,” Palmer said. “They are, like all of the laws we support, a commonsense measure that saves lives while not impeding anyone’s (Second Amendment) rights.”

The waiting period bill narrowly passed last session with a three-vote margin in the House and by a single vote in the Senate. Gov. Janet Mills said she was “deeply conflicted” about the bill when she allowed it to become law on Aug. 9 without her signature.

Internal communications obtained by the Press Herald through a public records request show that Mills’ chief legal counsel had requested a veto letter be drafted while Mills was considering whether to sign the bill.

Advocates argue that a waiting period could help reduce gun violence by providing a “cooling off period,” especially for potential suicides, since they are impulsive acts.

Gun rights advocates, however, argue that the law would violate the U.S. Constitution by burdening responsible gun owners. They worried the law would hurt the state economy and endanger people who need to quickly obtain a weapon for self-defense.

Gun advocates worried about the impact a waiting period would have on gun shows, which are an important fundraising tool for outdoor clubs. A three-day waiting period means people who purchase guns at a show must either travel to the seller’s storefront, or pay to have the firearm shipped to a closer dealer to be picked up after the waiting period is over.

The Legislature approved the bill on April 17. The final vote was 73-70 in the House of Representatives. In the Senate, the bill passed 18-17 after Democrats employed an infrequently used procedural move allowing the votes of two absent senators to be taken into account.

Maine joined 12 other states and the District of Columbia in enacting a waiting period on firearms purchases when Mills allowed it to become law  despite being conflicted about the impacts it might have.

In Vermont, which passed a 72-hour waiting period on most firearms purchases last year, opponents filed a lawsuit in U.S. District Court in Burlington in December contending the new law violates the Second Amendment of the U.S. Constitution.