In the wake of a wide-ranging gun-control law signed by Gov. Maura Healey last July, opponents of that legislation collected the required number of signatures to suspend the law until voters could decide its fate through a referendum.

But Healey removed that option by signing an emergency preamble, which immediately enacted the law’s updated restrictions.

Among its measures, the law’s language changed the definition of “machine gun” to include bump stocks — a device that increases the rate of a weapon’s fire by using its recoil energy to make the trigger fire repeatedly.

Trigger cranks, “Glock” switches, and other modifications were also now subject to legal penalties.

That left opponents with only one option: ensuring that their quest to overturn the law qualifies as a ballot question in the 2026 election cycle.

That is until the Trump administration intervened by allowing at least one firearm enhancement device previously banned to make a comeback.

As a result, attorneys general in 16 jurisdictions, including Massachusetts, sued Monday to block a plan to redistribute thousands of devices that convert guns to machine guns, including distribution in states where such devices are prohibited by state law.

The lawsuit, filed in U.S. District Court in Maryland, contends the devices would not only expose residents of those states to a higher probability of deadly violence, but would be contrary to federal law that calls for their seizure. And it would cause federal officials to “aid and abet violations of state law” by distributing the devices in states, including Massachusetts, where they’re outlawed, the suit argued.

The decision to return almost 12,000 forced reset triggers — which fire hundreds of rounds a minute with one pull of the trigger — came in a settlement last month involving the Bureau of Alcohol, Tobacco, Firearms and Explosives, gun manufacturers and gun-rights groups.

“Weapons of war and tools of mass destruction like FRTs have no place or purpose in everyday society — nor in any home, community, or school within the Commonwealth,” said Massachusetts Attorney General Andrea Campbell.

“The ATF’s actions are a direct assault on every American’s inalienable right to feel safe in their homes, schools, and grocery stores — free from the fear or threat of gun violence. I will continue to defend enforcement against FRTs and fight to protect the safety and wellbeing of Commonwealth residents,” added Campbell.

“These devices enable firearms to fire up to 900 bullets per minute. The increased rate of fire allows carnage and chaos to reign on the streets,” said Maryland Attorney General Anthony Brown in a virtual press briefing Monday with New Jersey Attorney General Matthew Platkin and Delaware Attorney General Kathy Jennings.

“Everyone nearby becomes vulnerable to serious injury or death,” Brown said.

Under the Biden administration, the ATF classified forced reset triggers as “prohibited machine guns under federal law … and conducted extensive retrieval operations, seizing nearly 12,000 FRTs from the field,” according to the lawsuit.

But the Trump administration reversed course after issuing a Feb. 7 executive order titled “Protecting Second Amendment Rights.”

On May 16, the Justice Department announced a settlement with Rare Breed Triggers, a manufacturer of the devices based in Wichita City, Texas. Under the deal, the company agreed not to develop or design such triggers for handguns, to promote safe and responsible use of its products, and to enforce its patents to “prevent infringement that could threaten public safety.”

In exchange, the government agreed not to enforce any policy where an FRT is “contended to be” a machine gun, and to return by Sept. 30 any reset triggers seized or “taken as a result of a voluntary surrender.”

The National Association of Gun Rights, also a party to the settlement, said in a statement that the deal will survive any challenge from the “anti-gun attorneys general.”

“A federal court already ruled the government unlawfully seized thousands of legal triggers from law-abiding Americans — a decision that the ATF now acknowledges and accepts,” said Hannah Hill, vice president for the association. “These states lack standing to file this lawsuit, and they know it.”

But the states’ lawsuit highlights the impact of gun violence in their jurisdictions, where it said there were nearly 47,000 gun-related deaths in 2023. Illinois had the most such deaths that year, at 1,691.

Of the states represented at Monday’s briefing, Maryland recorded 737 gun-related deaths in 2023. New Jersey had 430 and Delaware had 124, according to the suit.

Massachusetts recorded an estimated 270 gun-related deaths in 2023.

“This is not a partisan issue. It is a public safety issue,” Delaware AG Jennings said. “The Trump administration’s deal to redistribute these deadly devices violates the law, full stop. It undermines public safety and ties the hand of law enforcement.”

Of the suit’s plaintiffs, all but Maine and Vermont currently have state laws prohibiting forced reset triggers or firearms modified with them.

We agree with the Delaware attorney general. The wholesale redistribution of these potentially lethal devices constitutes a grave public-safety threat — no matter your party affiliation.

States that have banned devices like forced reset triggers and bump stocks shouldn’t now be compelled to allow their use.

Hopefully, those Maryland U.S. District Court justices will agree.