A federal appeals court in North Dakota has found that a rule issued by the Bureau of Alcohol Tobacco, Firearms and Explosives (ATF) that restricts ownership of pistol attachments known as stabilizing braces is "arbitrary and capricious," ordering a lower court to re-consider a motion that would block enforcement of the brace ban.

In a 2–1 decision issued on Aug. 9 by the 8th Circuit Court of Appeals, the majority found that a coalition of 25 Republican attorneys are likely to succeed in their legal challenge against the ATF rule that treats pistols fitted with stabilizing braces as short-barreled rifles and subjects them to various restrictions.

"The Final Rule, as a whole, is arbitrary and capricious because it allows the ATF to arrive at whatever conclusion it wishes without 'adequately explain[ing] the standard on which its decision is based,'" the majority opinion states. "Thus, we conclude the Coalition is likely to succeed on the merits of its challenge."

The states and other plaintiffs sued the ATF in February 2023, with U.S. District Judge Daniel Hovland in North Dakota declining to grant their motion for a preliminary injunction and block the rule. Arguing that they were unlikely to succeed on the merits, Hovland found that ATF had adequately explained its rulemaking process.

The majority on the 8th Circuit disagreed, and in their Aug. 9 decision ordered Hovland to reconsider the plaintiffs' motion for a injunction that would block the ATF rule's enforcement.

"We reverse the order denying a preliminary injunction and remand with instructions to reconsider the motion consistent with this opinion," the judges wrote in the majority opinion.

Circuit Judge Bobby Shepherd dissented, saying that the panel should have affirmed Hovland's order because there was no need for a preliminary injunction after the rule was vacated in June by U.S. District Judge Reed O'Connor in Texas.

O'Connor argued in his 12-page decision that the ATF's rule that treated roughly 99 percent of pistols fitted with the braces as short-barreled rifles violated the Administrative Procedures Act's procedural requirements because it was not a "logical outgrowth" of the proposed version of the rule.