Today’s the last day to submit your public comment to the ATF’s proposed rules redefining words like “frame,” “receiver,” “firearm,” and “readily,” as they apply to interpreting the Gun Control Act and the National Firearms Act. Already more than 240,000 comments have been received, and one of them comes from the National Rifle Association, which says in its own public comment that the proposed rule is a “clear violation” of the Administrative Procedure Act, which sets the rules by which federal agencies develop and issue rules and regulations.

For decades, the firearm industry, NRA members, and other American gun owners have dealt with (mostly) consistent rules regarding the core questions in federal firearms law. With the proposed rule, ATF abandons this consistency and upsets decades of reliance on existing rules. The long history of the existing definitions also proves that there has not been an issue with their clarity. In the case of these statutory definitions, which have remained consistent for the better part of a century, it is very obvious that “Congress has directly spoken to the precise question at issue.”

In fact, it is hard to imagine a case where Congress has spoken with greater clarity on a statute with this longevity and where an administrative agency nonetheless refuses to “give effect to the unambiguously expressed intent of Congress.”

In other words, if the Biden administration wants to impose these new restrictions on the right to keep and bear arms, it needs to use the legislative branch to pass a bill rather than use an executive branch agency’s regulatory power.

The NRA’s response takes specific issue with each and every word or phrase that the ATF is hoping to redefine, including “frame” and “receiver.” In the those particular cases, the organization says that the ATF’s proposal would offer different definitions depending on the type of firearm.

That alone is not the most serious problem with the proposed definition, but ATF’s conclusion that a firearm can have more than one “frame or receiver” is contrary to the statute and inconsistent with half a century of agency practice. Under the current definition, “firearm frame or receiver” means “[t]hat part of a firearm which provides housing for the hammer, bolt or breechblock, and firing mechanism, and which is usually threaded at its forward portion to receive the barrel.”

As noted in the proposed rule, in recent years, ATF has struggled to sustain application of this definition to certain firearm designs. See, e.g., United States v. Rowold, 429 F. Supp. 3d 469 (N.D. Ohio 2019). Rather than make modest changes to account for the issues identified in these cases, ATF has chosen to completely discard the existing regulatory framework.

ATF proposes a base “frame or receiver” definition of: A part of a firearm that, when the complete weapon is assembled, is visible from the exterior and provides housing or a structure designed to hold or integrate one or more fire control components, even if pins or other attachments are required to connect those components to the housing or structure. Any such part identified with a serial number shall be presumed, absent an official determination by the Director or other reliable evidence to the contrary, to be a frame or receiver. For purposes of this definition, the term “fire control component” means a component necessary for the firearm to initiate, complete, or continue the firing sequence, including any of the following: Hammer, bolt, bolt carrier, breechblock, cylinder, trigger mechanism, firing pin, striker, or slide rails. 86 Fed. Reg. at 27,742.

There are three main issues with this proposed definition. First, it would include parts that do not bear any reasonable resemblance to a firearm’s frame or receiver under the common industry understanding of the term. Under the proposed definition, a bolt carrier or slide might be considered a “frame or receiver” because they both can be “visible from the exterior” and “provide housing” for the “firing pin.”

Additionally, the NRA says that the presumption of a serial number is “contrary to industry practice,” pointing out that many gun makers may choose to serialize multiple gun parts for internal control purposes. As a result, they say, “the mere appearance of a serial number on a part is not necessarily indicative that part is a ‘frame or receiver.'”

The NRA also objects to the ATF’s idea that there can be multiple parts of a firearm that could be defined as frames or receivers. In fact, they cite the ATF itself in their comment, pointing out that the agency acknowledged in its own proposal that Congress specifically created a single frame or receiver as part of its definitions of a firearm.

While it is odd that ATF cites legislative history that undermines its own new proposed definition, resorting to legislative history is unnecessary in this case because the statute clearly refers to a singular part. The definition of firearm includes “the frame or receiver of any such weapon . . . .” 18 U.S.C. § 921(a)(3) (emphasis added).

When Congress wanted to create a definition that included multiple parts of a “firearm,” it knew how to do so. The definition of “firearm silencer” or “firearm muffler” applies to “any combination of parts, designed or redesigned, and intended for use in assembling or fabricating a firearm silencer or firearm muffler, and any part intended only for use in such assembly or fabrication.” 18 U.S.C. § 921(a)(24). If Congress had intended multiple parts of other firearms to be “firearms,” it could easily have enacted a similar provision.

Now, I doubt very much that the NRA’s comments (or the hundreds of thousands of other comments in opposition) are going to persuade the Biden administration to back off its proposal. Instead, we’re probably getting a sneak peek at some of the legal arguments that will be used to challenge the ATF’s new rules when they’re finalized. The NRA’s argument is a good one, but I suspect that it will find far more favor in a court of law than inside the White House.