A federal judge has blocked the Biden administration from enforcing a new rule in Texas that would require firearms dealers to run background checks on buyers at gun shows or other places outside brick-and-mortar stores.

The decision by U.S. District Judge Matthew Kacsmaryk, an appointee of former President Donald Trump, came before the rule had been set to take effect Monday. The order also prevents the federal government from enforcing the rule against several gun-rights groups, including Gun Owners of America. It does not apply to Louisiana, Mississippi and Utah, which were also part of the lawsuit.

“Plaintiffs understandably fear that these presumptions will trigger civil or criminal penalties for conduct deemed lawful just yesterday,” Kacsmaryk said in his ruling.

The federal Bureau of Alcohol, Tobacco, Firearms and Explosives declined to comment. The Justice Department didn’t immediately respond to a request for comment.

Twenty-six Republican attorneys general filed lawsuits in federal court in Arkansas, Florida and Texas aiming to block enforcement of the rule earlier this month. The plaintiffs argued that the rule violates the Second Amendment of the U.S. Constitution and that President Joe Biden, a Democrat, doesn’t have the authority to implement it.

The new requirement is the Biden administration’s latest effort to curtail gun violence and aims to close a loophole that has allowed unlicensed dealers to sell tens of thousands of guns every year without checking that the potential buyer is not legally prohibited from having a firearm.

Kacsmaryk wrote that the rule sets presumptions about when a person intends to make a profit and whether a seller is “engaged in the business.” He said this is “highly problematic” for multiple reasons, including that it forces the firearm seller to prove innocence rather than the government to prove guilt.

“This ruling is a compelling rebuke of their tyrannical and unconstitutional actions that purposely misinterpreted federal law to ensure their preferred policy outcome,” Gun Owners of America senior vice president Erich Pratt said in a statement Monday.

Biden administration officials proposed the rule in August and it garnered more than 380,000 public comments. It follows the nation’s most sweeping gun violence prevention bill in decades, which Biden signed in 2022 after lawmakers reached a bipartisan agreement in the wake of the Uvalde Elementary School shooting that killed 19 children and two teachers two years ago this week.

The rule implements a change in the 2022 law that expanded the definition of those who are “engaged in the business” of selling firearms, are required to become licensed by the ATF, and therefore must run background checks.

“This is going to keep guns out of the hands of domestic abusers and felons,” Biden said in a statement last month. “And my administration is going to continue to do everything we possibly can to save lives. Congress needs to finish the job and pass universal background checks legislation now.”

Kacsmaryk is the sole district court judge in Amarillo — a city in the Texas panhandle — ensuring that all cases filed there land in front of him. Since taking the bench, he has ruled against the Biden administration on several other issues, including immigration and LGBTQ protections.