Litigation Highlight: Legal Challenges to ATF Rule on Stabilizing Braces

In January of this year, the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) published Final Rule 2021R-08F, “Factoring Criteria for Firearms with Attached ‘Stabilizing Braces.’” The new rule changes the operative definition of “rifle” in the Code of Federal Regulations such that most pistols with attached stabilizing braces (often called “pistol braces”) will now be subject to heightened federal regulation under the National Firearms Act of 1934 (NFA) and the Gun Control Act of 1968 (GCA). Citizens, state attorneys general, and gun policy groups have already filed several lawsuits in federal district courts challenging the legality of ATF’s rule.

In this post, I’ll first introduce the pistol brace and the tale of historical (non)regulation, beginning with a brief table-setting history of the NFA and GCA. Second, I’ll survey the main legal arguments presented in the ongoing lawsuits, with a focus on Second Amendment challenges.

The NFA, GCA, and the “Short-Barreled Rifle” Category

The NFA, passed in 1934 in response to widely-publicized incidences of gang violence, imposed burdensome taxes, regulatory requirements, and criminal non-compliance penalties on the ownership and transfer of weapons associated with criminal use. In 1968, the GCA modified the definitions of certain weapons already regulated by the NFA and instituted a system of federal licensing for firearms distributors. Together, these two acts regulate machine guns (fully-automatic rifles like the “Tommy Gun,” infamously associated with Prohibition-era criminals); short-barreled rifles and shotguns; suppressors; destructive devices (like grenades and other explosives); and an amorphous category of “any other weapon” (now referred to as ‘AOWs,’ and understood to include ‘disguised’ firearms and firearms that don’t fit neatly into another category). Collectively, these weapons are known as “NFA items.”

More specifically, this regulatory scheme limits who may import, build, or purchase NFA items, and under what circumstances they may do so. The most onerous restriction at the time of the NFA’s passage was the $200 tax it imposed on possession of NFA items (equivalent to ~$4,500 in today’s dollars). Since the amount of this tax has not changed over the years, the tax itself is no longer the NFA’s most restrictive element. Instead, that honor now belongs to ATF’s ‘approval’ requirements, which involve extensive background checks and fingerprinting, as well as the registration of the individual NFA item with ATF. The average wait-time for an individual seeking to buy an NFA item, such as a short-barreled rifle (SBR), is estimated to be  270 days.

The NFA as originally written also regulated handguns, but a concerted lobbying effort on the part of the National Rifle Association caused lawmakers to drop handguns from the final bill. So, today, the NFA regulates neither handguns (defined in relevant part as “a firearm which has a short stock and is designed to be held and fired by the use of a single hand”) nor full-length rifles (defined in relevant part as “weapon[s] designed or redesigned, made or remade, and intended to be fired from the shoulder” and having a barrel longer than 16 inches). Since neither handguns nor full-length rifles are subject to NFA regulations, these two types of firearms are substantially easier to access than SBRs, which differ from full-length rifles only in their barrel length.

Take the AR-15 platform as an example. A citizen with a clean record can walk into a gun shop and buy an AR-platform pistol or a full-length AR rifle with little to no wait (depending on state laws). But the same buyer would have to wait the better part of a year to purchase a mid-length AR classified as a short-barreled rifle (in addition to registering the gun with ATF, submitting fingerprints and photographs for identification, and paying $200). Each of these weapons fire the same type of bullet using substantially the same technology, but only one of them is subject to heightened regulation. Despite the hurdles of the NFA, SBRs remain popular with gun owners because they combine the lighter weight of a pistol with the modular customizability of a rifle; indeed, over half a million SBRs were registered with ATF as of May 2021.

The Pistol Brace, and How (Not) to Use One

A pistol brace is an accessory that attaches to the rear of a heavy pistol and allows it to be shot more easily with one hand (see the image below). The brace usually contains some kind of strap or hook that attaches to the operator’s forearm; this mechanism connects more of the arm to the weapon, reducing recoil and facilitating safe and stable aiming.

The brace was originally designed for use by operators with disabilities or small physiques. Indeed, when the first pistol brace was manufactured and submitted to ATF for classification in 2012, ATF recognized its legitimate use as part of a pistol set-up and found that attaching such a brace did not alter the weapon’s design so drastically that the resultant weapon was “designed… to fire… from the shoulder” (which, if true, would classify the weapon as an SBR and subject it to NFA regulation).

But, in the intervening years, ATF has changed its position on the legal status of pistol braces multiple times. Part of the reason for ATF’s inconsistency is the not-so-secret knowledge (among pistol owners) that certain braces allow a pistol to be shoulder-mounted like a rifle would be—instead of strapping it to your forearm, you can just shoulder it like a typical rifle stock. Seemingly aware of this, ATF has said at times that simply firing a braced pistol from the shoulder does not convert the weapon into an SBR; at other times, it has said the opposite. But, regardless of ATF’s changing position (or perhaps because of it), pistol braces have become popular among gunowners; indeed, by ATF’s own estimates, there are somewhere around 3 million braces currently in circulation.

Against this backdrop, ATF published a Notice for Proposed Rulemaking on June 10, 2021 entitled “Factoring Criteria for Firearms with Attached ‘Stabilizing Braces.’” ATF announced its intention to alter the definition of “rifle” in 27 CFR sections 478.11 and 479.11 to clarify when the use of the pistol brace would convert a pistol into an SBR. The notice also contained a worksheet that ATF said would be used to classify other weapons and devices in the future.

On January 31, 2023, after reviewing over 237,000 comments, ATF published Final Rule 2021R-08F. The Final Rule scraps the proposed classification worksheet but maintains the new definition of “rifle,” under which the presence of a pistol brace “that provides surface area that allows the weapon to be fired from the shoulder” will cause the weapon to be classified as a rifle “provided that other factors” suggest the same. Since these “other factors” (including, for example, total weight, length-of-pull, and the presence of raised optics) are almost always present in some combination in heavy pistol set-ups, the Final Rule has the effect of classifying almost all braced pistols as SBRs (99%, in ATF’s estimation). The Final Rule is effective immediately, but gives current brace owners until May 31, 2023 to either register their braced weapon with ATF (during which time the $200 fee will be waived), or else forfeit, destroy, or alter their braced weapon to bring it into compliance.

Recent Litigation Challenging the ATF Rule

Since the Final Rule took effect in January, seven separate cases have been brought in the federal district courts challenging its legality.[1] Many of the cases raise similar legal arguments, so I’ll generally refer to the cases as a group. Briefly, though, it’s worth mentioning some of the parties who have signed on as plaintiffs. One case in the District of North Dakota is brought by the Firearms Regulatory Accountability Coalition joined by attorneys general from twenty-five different states, with 33 members of Congress as supporting amici. Another case in the Southern District of Texas is being brought by the Texas attorney general, alongside the Gun Owners of America and the Gun Owners Foundation. And, in a third case, the Firearms Policy Coalition has joined with Maxim Defense (a manufacturer of pistol braces) to file a lawsuit in the Northern District of Texas.

As of this writing, most cases haven’t advanced beyond their initial complaints. However, in the three cases mentioned above motions for preliminary injunction have been filed, and ATF has responded in the North Dakota case.

Legal Arguments Against the Final Rule

The most common set of legal challenges lodged in these cases characterize the Final Rule as a violation of the Administrative Procedure Act, or APA. The specific form of violation alleged differs across the cases, but they collectively include allegations that the Rule is: ultra vires, arbitrary and capricious, unconstitutionally vague, equitably estopped, and noncompliant with notice-and-comment procedures, among others.

Some of these APA claims seem stronger than others. For example, the argument that ATF lacks delegated powers to alter the NFA’s ambit (in as significant a manner as this Rule does) seems more colorable than the claim that ATF violated notice-and-comment procedures (since ATF seems to have followed standard protocol throughout the open comment period that began in 2021). The equitable estoppel argument is also noteworthy, if not particularly likely to succeed. Since pistol brace owners purchased and equipped their braces in compliance with prior ATF statements suggesting that an attached brace does not convert a pistol into an SBR (the argument goes), ATF is estopped from enacting a Rule that imposes NFA regulations on those same brace owners and criminalizes their non-compliance. It seems that, if this argument were successful, it would act as a one-way ratchet, allowing administrative agencies to loosen regulations without being able to tighten them later on.

But, regardless of their strengths and weaknesses from the perspective of administrative law, these APA claims may nonetheless find success in some district courts for a practical reason. If a judge wants to rule for the plaintiffs, the judge is perhaps more likely to strike down the Rule on APA grounds rather than on Second Amendment or other constitutional grounds, since the latter route might require the constitutional invalidation of entire sections of the NFA, a taller task to be sure. (More on this possibility below.)

Besides the APA challenges, other pleaded claims allege separation of powers violations (which are the focus of the congressional amicus brief in FRAC v. Garland); taxing power violations (on the theory that, since ATF is waiving the $200 fee until May 31st, they aren’t actually levying a tax, rendering the rule ultra vires); and Fifth Amendment takings clause violations (for braced pistol owners in states that regulate or outright ban the possession of SBRs). Finally, multiple briefs assert that the rule of lenity must be applied when interpreting the NFA, since it prescribes criminal fines and possible jail time for violations of its taxing and registration scheme. This argument was endorsed in the recent en banc 5th Circuit decision in Cargill v. Garland, which struck down ATF’s 2018 Rule redefining “machinegun” to include semi-automatic weapons with attached bump stocks. The statutory definitions at issue in the pistol brace cases seem more straightforward than the text at issue in Cargill, though, so it’s not clear that the rule of lenity (a canon of statutory interpretation) will have much of a role to play in these cases.

On the Second Amendment

To me, the most interesting aspects of these lawsuits are the Second Amendment claims. Even though these cases are ostensibly about pistol braces—a weapon attachment—some of the arguments seem to call into question the constitutionality of the NFA itself, insofar as it regulates short-barreled rifles as a distinct category of “arms.” I’ve written more extensively about the operation of Bruen’s text-and-history test elsewhere, but the main issue here is whether or not the relative historical recency of laws regulating firearms based on their barrel lengths puts a portion of the NFA in constitutional jeopardy.

Take the Texas v. ATF case as an example. Texas’s argument can be summed up thusly: braced pistols are either pistols or short-barreled rifles, and since the possession of both weapons is presumptively protected by the Second Amendment (because they’re both weapons in common use for lawful purposes), ATF must show a “historical tradition” of laws pre-dating the NFA, presumably from the Founding era, that regulated weapons similar to braced pistols in order to prove the constitutionality of its new rule. Texas submitted photographs of several short-barreled rifles (and long-stocked pistols) from the Founding era, and claimed that no laws regulated firearms based on barrel length until the NFA in 1934. (The latter claim seems to be contradicted outright by several 20th-century, pre-NFA laws that appear to do just that, though their temporal distance from the Founding may render them insufficient to prove a “historical tradition” of similar laws as required by Bruen.)

ATF may respond by arguing that pistol braces simply aren’t “arms,” and that braces therefore lack the constitutional protection that Texas presumes they have. This argument recently saw success in a Rhode Island district court case called Ocean State Tactical v. Rhode Island, where a court denied a preliminary injunction against Rhode Island’s ban on high-capacity magazines. In the Texas case, though, the plaintiff likely has the better of the argument. Unlike the law at issue in Ocean State Tactical, which regulated possession of a weapon accessory, ATF’s rule does not prohibit (or even regulate) the possession of pistol braces themselves—it only places new regulations on braced pistols (i.e., pistols with a brace attached). So, regardless of whether braced pistols are considered “rifles” (as the new Rule would have it) or pistols (as they used to be), the new Rule targets a weapon in common use for lawful purposes—the braced pistol—and must therefore withstand scrutiny under the Second Amendment.

So, it seems Texas has its sights set higher than ATF’s pistol brace rule—the state is aiming at the NFA itself. Indeed, Texas’s complaint reflects a common sentiment among gun owners: why are SBRs subject to NFA regulation if pistols and rifles are exempt? Full-length rifles don’t get any special regulation—does a single inch in barrel-length really make that much of a difference? If Congress decided that SBRs are “dangerous and unusual” because of their concealability, why are pistols—the concealable firearm par excellence—exempt from the same regulations? Besides (the argument goes), an SBR is a lot closer to an AR-platform rifle or a standard-weight pistol than it is to a grenade launcher, a fully-automatic machine gun, or even a sawed-off shotgun—should SBRs really be included in the company of those “dangerous and unusual” weapons?

In the past, advocates of heightened firearm regulation could respond by saying: “Yes, it is strange that SBRs are treated differently than rifles and pistols… but the solution is to treat all guns like NFA items, rifles and pistols included.” However reasonable this retort may sound, the truth is that the regulatory scheme it proposes might not pass constitutional muster in the post-Bruen era, since laws classifying guns based on barrel length seem to be mainly a product of the 20th century (not the Founding era). Because of this potential constitutional roadblock, the opinion that both of these perspectives share—that SBRs should probably be treated like other rifles—is more likely to lead to the conclusion that SBRs shouldn’t be regulated as NFA items at all.

There will surely be more to discuss as these cases wind their way through the federal courts, especially pertaining to ATF’s power as a rulemaking entity. But regardless of what fate befalls ATF’s pistol brace rule, it seems that this litigation has already cleared the path for an as-applied Second Amendment challenge to the NFA’s SBR regulations—a challenge which might have serious legs in the wake of Bruen.

[1] The seven cases are: FRAC v. Garland, 1:23-cv-00024 (D.N.D.); Texas v. ATF, 6:23-cv-00013 (S.D. Tex.); Mock v. Garland, 4:23-cv-00095 (N.D. Tex.); Colon v. ATF, 8:23-cv-00223 (M.D. Fla.); Second Amendment Foundation v. ATF, 3:21-cv-00116 (N.D. Tex.); Britto v. ATF, 2:23-cv-00019 (N.D. Tex.); and Watterson v. ATF, 4:23-cv-00080 (E.D. Tex.).