The Court is likely done with this rule, but litigation of its applications in the lower courts is apt to continue.

I warned back in October, after the argument in Bondi v. VanDerStok (then captioned Garland v. VanDerStok) that the Supreme Court seemed unexpectedly willing to uphold the Biden-era Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) regulation on so-called “ghost guns,” i.e., the practice of buying kits that could modify certain unfinished gun parts into a gun. That potential outcome seemed surprising given the rigorous view of the language of the Gun Control Act of 1968 (GCA) taken when the Court struck down the Trump-era ATF’s bump-stock ban last June in Garland v. Cargill, with all six of the Court’s Republican appointees joining Justice Clarence Thomas’s majority opinion limiting the definition of “machinegun” by reference to the mechanical function of the gun itself.

This morning, only Thomas and Justice Samuel Alito were willing to strike down the ghost gun rule, which the Court upheld 7–2 in an opinion written by Justice Neil Gorsuch. Thus, the gun-rights side lost not only the votes of Chief Justice John Roberts and Justice Amy Coney Barrett, who had sided with the ATF on keeping in place the injunction staying the ATF’s rule while the case was pending, but also Gorsuch and Justice Brett Kavanaugh. (The three liberals, as usual, voted for their preferred outcome). Kavanaugh, ever concerned about state-of-mind issues in criminal cases, added a short concurrence attempting to hold the Justice Department to its contention in litigation that it would not prosecute people who may not have been previously on notice of what the rule reaches.

As Charlie Cooke explained the stakes in the case, the ATF rule unsettled longstanding expectations about what the statute did and did not cover:

Before one can regulate firearms in a statute, one needs to define what a firearm is — or, more specifically, one needs to define which part of a firearm has been deemed to turn a firearm into “a firearm.” Experience has shown that it is impractical for each and every component to be cast as the decisive piece, and so, for more than half a century, federal law has distinguished between ancillary elements such as triggers, magazines, barrels, and so forth, and sine qua non elements such as “frames” and “receivers.” If, for example, one wishes to assemble an AR-15, one is obliged to submit to a background check when acquiring only one piece of the gun: a large piece of metal, about the same size as an adult’s hand, to which all of the other key parts of the weapon are connected. That piece is called the “lower receiver.” Since the passage of the Gun Control Act of 1968, the term “lower receiver” has been held to cover only those finished devices that can be attached to the rest of the gun without further amendment. But, in 2022, the Biden administration attempted to alter this unilaterally. Henceforth, the ATF announced that year, the term “receiver” would “include a partially complete, disassembled, or nonfunctional frame or receiver, including a frame or receiver parts kit, that is designed to or may readily be completed, assembled, restored, or otherwise converted to function as a . . . receiver.” Or, to put it another way: from then on, “receiver” would not just mean “receiver,” but would include anything that could, if further manufactured, plausibly become a receiver.

The purpose of this change was to extend the 1968 Gun Control Act to encompass what are commonly referred to as “80 percent lowers” — that is, to encompass pieces of receiver-shaped metal that cannot currently be attached to a trigger or any other key part of a rifle, but that are able to be so attached once they have been subjected to additional fabrication.

Put in statutory terms by the Fifth Circuit:

The GCA defines a “firearm” as: “(A) any weapon . . . which will or is designed to or may readily be converted to expel a projectile by the action of an explosive; (B) the frame or receiver of any such weapon; (C) any firearm muffler or firearm silencer; or (D) any destructive device.” [18 U.S.C.] § 921(a)(3)(C). As no definition for “frame or receiver” is given in the GCA, ATF previously defined a “frame or receiver” in 1978 as: “That 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.” . . . This definition remained unchanged for over forty years, until ATF issued the Final Rule in 2022. [Emphasis added.]

Judge Andrew Oldham’s thundering concurrence in the Fifth Circuit warned, “because AR-15 receivers can be readily converted into machine gun receivers, that this regulation on its face turns everyone who lawfully owns an AR-15 into a criminal.” The rule, he concluded, “is limitless. It purports to regulate any piece of metal or plastic that has been machined beyond its primordial state for fear that it might one day be turned into a gun, a gun frame, or a gun receiver. And it doesn’t stop regulating the metal or plastic until it’s melted back down to ooze. The GCA allows none of this.” My own take at the time:

The really glaring problem for the ATF is that the statute covers guns, it covers things readily converted to function as guns, and it covers certain specific parts of guns (i.e., the receiver), but it pointedly does not cover things readily converted into parts of guns. Congress could have said “the frame or receiver of any such weapon or anything which may readily be converted to a frame or receiver,” but it didn’t.

Gorsuch and the majority saw things differently. The Court began with technological change:

Recent years . . . have witnessed profound changes in how guns are made and sold. When Congress adopted the GCA in 1968, the milling equipment, materials needed, and designs were far too expensive for individuals to make firearms practically or reliably on their own. . . . With the introduction of new technologies like 3D printing and reinforced polymers, that is no longer true. Today, companies are able to make and sell weapon parts kits that individuals can assemble into functional firearms in their own homes. [Quotation and citation omitted.]

Of course, there are times when the Court needs to apply old statutory language to new technologies, and times when it needs to tell Congress that if it wants to regulate something new, it needs to write a new law. Much depends upon how the statute was written in the first place.

Gorsuch began by noting that the challengers carried a heavier burden because they were bringing a facial challenge — i.e., arguing that the new rule clearly exceeded the agency’s authority under the statute — rather than challenging “whether ATF’s new regulations . . . may be lawfully applied to particular weapon parts kits or unfinished frames or receivers,” a question the Court left open. The Court, unlike the Fifth Circuit, focused more on the kits and their capacity to become weapons than on the frame-or-receiver definition:

The GCA authorizes ATF to regulate “any weapon (including a starter gun) which will or is designed to or may readily be converted to expel a projectile by the action of an explosive.” Inhering in this language are two requirements. First, a “weapon” must be present. Second, that “weapon” must meet one of three criteria: It must be able to expel a projectile by the action of an explosive, designed to do so, or susceptible of ready conversion to operate that way. As the Fifth Circuit saw it, [the Rule’s] provisions addressing weapon parts kits are facially invalid because no weapon parts kit can ever satisfy the statute’s two requirements. We disagree because, to our eyes, at least some kits will satisfy both. . . .

As sold, the kit requires some assembly. But a number of considerations persuade us that, even as sold, the “Buy Build Shoot” kit qualifies as a “weapon.” Consider, first, a feature of ordinary language. The term “weapon” is an artifact noun — a word for a thing created by humans. Artifact nouns are typically characterized by an intended function, rather than by some ineffable natural essence. . . . Reflecting as much, everyday speakers sometimes use artifact nouns to refer to unfinished objects — at least when their intended function is clear. An author might invite your opinion on her latest novel, even if she sends you an unfinished manuscript. A friend might speak of the table he just bought at IKEA, even though hours of assembly remain ahead of him. In both cases, the artifact noun fits because the intended function of the unfinished object is obvious to speaker and listener alike. [Italics in original; quotations and citations omitted.]

At the argument, there was a back-and-forth between hypotheticals proposed by Alito: that a pen and paper do not equal a grocery list, and a set of omelet ingredients do not equal an omelet, but perhaps a pre-packaged omelet-making kit did. The kits here clearly looked more to the majority like the latter: “Even as sold, the kit comes with all necessary components, and its intended function as instrument of combat is obvious. Really, the kit’s name says it all: ‘Buy Build Shoot.’” Gorsuch cautioned, however, that the statute’s ready-conversion test could have limits in practice when applied to specific kits, a conundrum he explained in terms that would do a medieval scholastic monk proud:

Start with a heap of sand and begin removing grains; at some point, a heap no longer exists. That problem attends many artifact nouns. Even when used to capture unfinished products, artifact nouns generally reach only so far. It would be extravagant to speak of a novel when the author has dashed off only a few lines. Few would call a pile of unfinished logs a table.

That may bode well for future challenges to the application of the rule to kits that require more craftsmanship to finish. For example:

The plaintiffs criticize ATF’s rule for permitting the agency to consider “jigs,” “tools,” and “instructions” when deciding whether an incomplete “frame or receiver” is close enough to the finished product to fall under subsection (B). . . . But if this is a problem at all, it is one for another day. As litigated, this case does not call on us to address what weight, if any, ATF may lawfully give jigs, tools, and instructions when deciding whether a frame or receiver is present. This case requires us to answer only whether subsection (B) reaches some incomplete frames or receivers. Saying that it does is enough to resolve the dispute before us.

The Court is likely done with this rule, but litigation of its applications in the lower courts is apt to continue.