The Fifth Circuit just ruled against the feds in the Firearm Policy Coalition case on the new ATF rule on pistol braces as short-barrel rifles.

Federal Appeals Court Finds ATF Pistol Brace Rule Is Likely Unlawful: ‘Impossible For A Regular Citizen’
Smith wrote that the rule makes it “nigh impossible for a regular citizen to determine what constitutes a braced pistol” and whether “a specified brace pistol requires NFA registration.”

No kidding. The Zelman Partisans noted that more than two years ago, when the Notice of Proposed Rule-Making was published.

This proposed rule is a coherently expressed description of an arbitrary, capricious, and incoherent process of classifying firearms.

As no standards were given, a subjective examiner’s guesstimate of “rear surface area” could pass a brace, or put it right on the edge of alleged short-barreled rifle by itself. Will one examiner estimate the “rear surface area” of a cuff-type brace by the physical area of the rear EDGE of the cuff, while another goes by the area of the space ENCLOSED by the cuff?

After the commenting period was over, the actual rule even worse than what was proposed. They tossed their proposed “checklist,” and switched to a list of arbitrary characteristics that went undefined; it was left up to each individual evaluator.

If you scroll down to page 268, you’ll find the actual final rule, and see that they opted for a evaluation system even more “arbitrary, capricious, and incoherent” than the 4999.
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How much surface area does it take to create a rifle? The rule doesn’t say, leaving it up to “”arbitrary, capricious, and incoherent” FTB evaluators. Just think: the more firearms they can declare short-barrel rifles, the more tax money they can collect. No perverse incentive there, eh?

In short, braced pistol owners were left with two options to determine if their pistols had magically morphed into rifles: Send it to the ATF for individual determination, or wait to be arrested for possession of an unregistered short-barrel rifle.

This isn’t a final win. The Fifth Circuit panel only said that the rule is likely to be found to be unlawful. Based on that likelihood, they sent it back to the district court to reconsider an injunction against enforcement of the capricious rule.

I suspect this is going to bounce back and forth a while longer.