A judge just enjoined a law restricting the sale of popular semi-automatic pistols that critics claim can be too easily converted into machine guns, hours before it was set to take effect.

US District Judge Kari A. Dooley issued a preliminary injunction Wednesday against Connecticut’s Public Act 26-41. She found plaintiffs in two lawsuits challenging the law were likely to succeed on their Second Amendment claims. The law was scheduled to take effect on Thursday, but won’t go into effect unless and until the injunction is lifted. 

“The statute is presumptively unconstitutional, and Defendants have not met their burden of demonstrating that the statute is consistent with our nation’s history of firearms regulation,” Judge Dooley wrote in Glock v. Griffin.

The ruling temporarily stops Connecticut from enforcing restrictions on certain semi-automatic pistols based on their potential to be illegally converted into machine guns. It represents the first win for gun-rights activists and the gun industry in the legal fight over the new laws, often referred to as “Glock bans” because they target the underlying design of the popular brand’s pistols, which a growing number of states have adopted in the past few years. It comes a few months after a federal judge in California declined to issue a similar order in the Department of Justice’s suit against that state’s version of the policy.

The case centers on whether the state can restrict firearms that have not themselves been converted when the government’s concern is that they could later be modified into illegal machine guns, an issue the judge evaluated under the Supreme Court’s historical-tradition framework for Second Amendment cases.

Connecticut Governor Ned Lamont (D.) signed House Bill 5043, later designated Public Act 26-41, in May. The law creates a new statutory category of “convertible pistols,” covering certain semi-automatic pistols with a “cruciform trigger bar” that can be converted into a machine gun by installing a pistol converter–often called a “Glock switch.” Distributing, transporting, importing, keeping for sale, or offering those firearms for sale is classified as a Class D felony under the law.

Austrian weapons manufacturer Glock filed a lawsuit challenging the law on September 21st, while Texas-based firearms manufacturer Shadow Systems, firearm industry trade group the National Shooting Sports Foundation (NSSF), and Connecticut-based shooting facility Blue Trail Range filed a separate lawsuit that same day. Both lawsuits argue that the law violates the Second Amendment.

Judge Dooley decided they are likely correct. He argued the state’s defense, that gun inspection or “proving” laws from the Founding Era are similar to its ban, did not pass muster.

“[T]he proving laws do not appear to sufficiently align with either the ‘how’ or the ‘why’ of HB 5043 so as to render them relevantly similar,” Judge Dooley, a Donald Trump appointee, wrote.

Glock also argues that some of its newer pistols may not qualify as “convertible pistols” under the law’s definition, but Judge Dooley declined to answer that question at the preliminary stage.

The firearms-industry plaintiffs argued that Public Act 26-41 would cause them to lose sales, customers, and business relationships. Blue Trail Range said it had about $25,000 worth of cruciform-trigger handguns in inventory and had stopped ordering additional firearms it believed would be covered by the law. They also argued that allowing them to sell firearms manufactured before October 1st would not address the loss of customers, including law enforcement personnel who are not exempt from the statute, as well as lost goodwill, disrupted contracts, and restrictions on advertising. Dooley agreed that the plaintiffs had demonstrated sufficient harm to warrant preliminary relief.

“In combination, the Court concludes that if not enjoined, enforcement of HB 5043 will cause irreparable harm to Plaintiffs,” Dooley wrote.

Connecticut officials criticized Dooley’s decision and vowed not to give up the fight. Attorney General William Tong (D.) said in a statement to The Reload that he “does not agree with the Court” and will “continue to defend the law.” Governor Lamont said he was “disappointed” by the ruling and that he and his team would “evaluate all legal options” to protect the state.

“We passed a commonsense law: you should not be able to turn a handgun into a machine gun with a simple piece of plastic,” he told The Reload. “Closing this loophole in our gun regulations is not only widely supported, but also desperately wanted by Connecticut residents.”

He claimed the bill had widespread support in the state.

“Students asked for this bill,” he said. “They worry about how much more harm these guns cause. Police asked for this bill. They are concerned about the rising number of convertible pistols showing up on our streets and the scenes of senseless tragedies, including the murder of a young mother and her baby in Hartford in 2024.”

NSSF had the opposite reaction. It praised Wednesday’s decision, reiterating its argument that Connecticut had improperly restricted the sale of one of the “most popular-selling self-defense handguns” in the United States.

“Connecticut politicians sought to ban an entire class of firearms because criminals who, by definition, ignore the law, can illegally alter those firearms and criminally-misuse them,” the group said in a statement. “Instead of holding criminals accountable for their crimes, Connecticut Gov. Lamont and gun control supporting politicians in the state sought to punish law-abiding citizens by denying them the full expression of their civil rights.”