The Supreme Court’s ruling overturning the long-standing “Chevron doctrine” on Friday dealt a major blow to the power of federal agencies.

It came as welcome news to gun rights groups.

The Biden administration managed to pass a modest gun reform bill two years ago called the Bipartisan Safer Communities Act. That law strengthened federal funding for violence prevention, helped fund the implementation of red flag laws, and took steps to close the so-called “boyfriend loophole” that had allowed offenders to avoid losing their gun rights after convictions of domestic abuse crimes against dating partners.

But facing Republican opposition in Congress to more sweeping reform proposals, the White House has also used the rulemaking authority of the Bureau of Alcohol, Tobacco, Firearms and Explosives to pursue two other gun safety measures.

Last year, the ATF reclassified guns equipped with pistol braces as short-barreled rifles under the National Firearms Act of 1934 after they were used in multiple mass shootings. The devices do not alter the destructive capacity of a pistol, though they can make them easier to aim.

The ATF rule did not ban pistol braces, but it tightened the requirements for buying them and slapped them with a $200 tax by classifying them alongside short-barreled shotguns, suppressors and pre-1986 machine guns.

And this year, the ATF enacted a farther-reaching rule that altered the definition of what it means to be “engaged in the business” of dealing firearms.

Before the change, the agency only considered people dealers if they earned a living selling guns. In an effort to crack down on unlicensed gun dealers, however, the lawmakers who passed the Bipartisan Safer Communities Act tweaked the definition of “engaged in the business” to apply to people who sold guns primarily to earn a profit. The White House directed the ATF the following year to issue a new rule specifying who would need a federal firearms license to sell guns.

The ATF’s definition, finalized in April, requires people to register as federal firearms dealers if they repeatedly attempt to sell guns with the intent of making a profit — even in cases where the seller fails to find a buyer. The rule would not consider people gun dealers if they occasionally sell a gun or liquidate an inherited collection. But the rule specifies that the agency would view private sellers as dealers if they advertise guns online or take out tables at gun shows.

The ATF estimates that the rule would affect about 25,000 people who currently sell guns without licenses. Selling firearms illegally is punishable by prison sentences of up to five years.

“There is a large and growing black market of guns being sold by people in the business of dealing and doing it without a license, and therefore they are not running background checks the way the law requires,” ATF director Steven Dettelbach said after publishing the final rule. “It’s not safe for innocent, law-abiding Americans.”

But both ATF changes stand on shakier ground after the Supreme Court overturned the 1984 ruling in Chevron v. Natural Resources Defense Council, which had given agencies wide latitude to interpret ambiguous laws. Friday’s ruling shifts that power to the courts.

“By overruling Chevron, the Court properly restored our constitutional order by ensuring that the judicial branch, rather than the executive, interprets the law,” Randy Kozuch, executive director of the NRA Institute for Legislative Action, wrote in a statement. “The ruling benefits NRA’s ongoing efforts to hold Biden’s rogue ATF accountable for exceeding its authority and punishing peaceable gun owners.”

The Biden administration had trumpeted the “engaged in the business” rule as an expansion of background checks that promised to close the so-called “gun show loophole.” Many states allow people to sell guns privately or at gun shows without documentation or oversight. Federal firearms licensees, however, must conduct a background check on buyers before selling a gun.

But Republican opponents and Second Amendment groups decried the change, accusing the White House of using ATF rulemaking as a backdoor way to pass an extension of background checks that Congress wouldn’t have passed. Sen. John Cornyn (R-Texas), who supported the Bipartisan Safe Communities Act, described the rule as a “flagrant distortion of congressional intent” back in May.

The rule has already faced setbacks in court. A coalition of gun rights groups and several states led by Texas won an injunction against the rule’s implementation this month from a federal judge in Amarillo.

In a separate decision, U.S. District Judge Sam Lindsay enjoined the rule imposing tougher restrictions on pistol braces.

The Supreme Court’s ruling will only bolster the case against the ATF rules, according to the National Shooting Sports Federation, the firearm industry trade group.

“The ‘engaged in the business’ rule and the pistol brace rule are dead on arrival,” said NSSF spokesman Mark Oliva. “They just need a day in court.”