Most Justices Seem Inclined To Uphold the ATF's New Restrictions on Homemade Firearms

The Supreme Court is considering whether a rule targeting "ghost guns" exceeds the agency's statutory authority.

The Supreme Court on Tuesday considered whether the Biden administration's restrictions on homemade firearms are consistent with the Gun Control Act (GCA) of 1968. As with the Trump administration's ban on bump stocks, which the Court rejected in June, the issue in Garland v. VanDerStok is not whether the rule violates the Second Amendment but whether it exceeds the authority that Congress gave the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF). Unlike in the bump stock case, however, most of the justices seem inclined to uphold the new regulations.

The ATF began enforcing those regulations in August 2023 after the Supreme Court temporarily blocked a ruling that vacated them. The U.S. Court of Appeals for the 5th Circuit subsequently endorsed the logic of that decision, saying the ATF rule "flouts clear statutory text and exceeds the legislatively-imposed limits on agency authority in the name of public policy."

The rule, which was published in April 2022, is aimed at banning what the administration calls "ghost guns," which are assembled from commercially available kits. Under prior regulations, manufacturers and sellers of those products did not have to obtain federal licenses, mark the parts with serial numbers, or conduct background checks on buyers. The new rule applies all three requirements to "any kits or nearly complete frames or receivers that can be readily converted into a firearm."

Defending the rule during oral argument on Tuesday, Solicitor General Elizabeth Prelogar told the Supreme Court it was necessary to control "untraceable guns" that "are attractive to people who can't lawfully purchase them or who plan to use them in crimes." Thanks to the availability of "easy-to-assemble kits and frames and receivers that require minimal work to be made functional," she said, "our nation has seen an explosion in crimes committed with ghost guns."

Whatever you make of that policy argument, it is distinct from the legal question of whether the ATF has the statutory authority to ban "ghost guns." Congress may be free to crack down on the kits and parts that worry Prelogar, but that does not necessarily mean the ATF can do so without new legislation. The agency's attempt to do so hinges on the legal definition of "firearm," which is what triggers the licensing, serial number, and background check requirements.

The GCA's definition of "firearm" covers "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." It also covers "the frame or receiver of any such weapon." The law does not define "frame or receiver." But as Peter Patterson, the attorney representing the individuals and gun rights groups that challenged the ATF rule, explained to the Court, "a frame or receiver is basically the part of a firearm that holds the components that allow a firearm to function, so the firing mechanism, the trigger and such, and the sealing component that makes sure that the barrel is sealed off so that the round goes out of the barrel and the energy from the explosion doesn't go elsewhere."

Under the ATF rule, Prelogar said, "a weapon parts kit that can readily be converted to function as a gun with common tools, often in under an hour, is a covered firearm." That interpretation seems counterintuitive, since the ATF is equating "a weapon parts kit" with what the GCA describes as a "weapon."

Under the same logic, Justice Samuel Alito wondered, would "a blank pad" and "a pen" constitute "a grocery list"? No, Prelogar said, "because there are a lot of things you could use those products for to create something other than a grocery list."

Alito tried a different hypothetical. Suppose "I put out on a counter some eggs, some chopped-up ham, some chopped-up pepper and onions," he said. "Is that a Western omelet?" Again no, Prelogar replied, because "those items have well-known other uses to become something other than an omelet. The key difference here is that these weapon parts kits are designed and intended to be used as instruments of combat, and they have no other conceivable use."

Justice Amy Coney Barrett had more success with another food analogy. "Would your answer change," she asked, if someone ordered a "turkey chili" kit from HelloFresh that included "all of the ingredients"?

Yes, Prelogar said, adding that if someone bought an "omelet-making kit" from Trader Joe's that "had all of the ingredients to make the omelet and maybe included whatever you would need to start the fire in order to cook the omelet and had all of that objective indication that that's what's being marketed and sold, we would recognize that for what it is. It doesn't stretch plain English to say 'I bought omelets at the store' if you bought all of the ingredients that were intended and designed to make them, especially under statutory language that refers to something like breakfast foods or things that can be readily converted to make breakfast."

Unlike Prelogar, I think it does "stretch plain English" to say "I bought omelets at the store" when you actually bought an "omelet-making kit." And the GCA does not refer generally to "things" that can be "readily converted"; it refers specifically to a "weapon." The ATF, Patterson noted, "has expanded the definition of 'firearm' to include collections of parts that are not weapons and that do not include a frame or receiver."

The ATF rule also raises the question of what counts as "readily converted." Prelogar said the courts and the ATF generally have understood that phrase to apply "if a novice, in a fairly quick amount of time, can easily and efficiently convert the weapon to function." Although she did not commit to a firm definition of "fairly quick," she said "the longest period of time that was ever deemed still readily convertible was eight hours."

Prelogar suggested that guns can be assembled from kits much faster than that. She said sellers have "touted that you can go from opening the mail to hav[ing] a fully functional gun in as little as 15 minutes." But as Stephen Halbrook notes, a former acting chief of the ATF's Firearm Technology Branch filed a brief in this case that shows "fabrication of a firearm from these kits is a complex process requiring skill and special tools beyond the capacity of the average person."

In addition to covering kits that can be "readily converted" into a working gun, Prelogar noted, the ATF rule says "a product is a frame or receiver under the act [and therefore a 'firearm'] even if the buyer must drill a few holes or remove a few superfluous pieces of plastic to make it functional." The ATF, she said, "is now taking account of jigs or templates, which are [tools] that quickly speed up the process of making a frame or receiver functional because they show you exactly where you have to drill in that weapon, so there's no trial and error or guesswork."

The new interpretation is problematic, Patterson argued, because the provision dealing with "a frame or receiver," unlike the other definition of "firearm," does not say anything about conversion. The ATF "has expanded the definition of 'frame or receiver' to include items that may readily be converted to a frame or receiver," Patterson noted. "'Readily convertible' is in the statute under Part A. It is not in the statute under Part B." It "would be very odd to say that…'readily convertible' is implicit in every term," he said, since Congress included that phrase in some parts of the statute but not in this one. He complained that the ATF is "taking language from another part of the statute that's not there and putting it there."

That reading, Patterson said, contradicts the ATF's prior position that "an unfinished frame or receiver does not meet the statutory definition of 'firearm' simply because
it can be designed to or can readily be converted into a frame or receiver." He also warned that the new interpretation would create problems under other parts of the statute.

"The government admits that sometimes drilling a single hole can be the difference between a semi-automatic receiver and a machine gun receiver," Patterson said. "And a machine gun receiver is much more heavily regulated than a semi-automatic receiver. So the notion that just one hole separating something from another item is somehow absurd is clearly not the case….If one hole is all that separates a semi-automatic receiver from a machine gun receiver, it's hard to see how the 'readily' standard would not also be applied there."

Barrett raised that issue with Prelogar, noting the concern that the ATF rule "on its face turns everyone who lawfully owns an AR-15 into a criminal" because "AR-15 receivers can be readily converted into machine gun receivers." That objection is misguided, Prelogar said, because "we are not suggesting that a statutory reference to one
thing includes all other separate and distinct things that might be readily converted into the thing that's listed in the statute itself."

A machine gun is "a weapon that's designed to fire automatically more than one
shot with a single function of the trigger," Prelogar said. "But you couldn't say that about an AR-15. That is obviously something that's designed and intended to be used for semi-automatic fire. And the fact that you might be able to undertake certain drilling and machining operations to convert it into a machine gun doesn't mean that, while it has this separate identity and is standing alone, it would be regulated as a machine gun."

The new understanding of "frame or receiver" is commensensical, Prelogar argued. "If you are missing a single hole, then you can clearly recognize that as an unfinished
component part of a weapon, and it is readily convertible to function," she said. "And that fits within the plain dictionary definition of what a frame or receiver is understood to be. No different than a bicycle missing pedals or a tennis racket that is sold unstrung."

Patterson offered two alternatives to the ATF's new definition of "frame or receiver." Either it has to be "completely machined," he said, or it has to pass the "critical machining" test that the ATF previously applied, which was colloquially known as "the 80 percent rule." Under that test, Patterson said, the ATF would "look at that part of the firearm and see if critical machining operations have taken place." And "as a crosscheck," he added, "there sometimes would be temporal considerations," which "were tied to the degree of machining."

Patterson is clearly hoping that the Court will force the ATF to revive that standard, which he said the agency arrived at after decades of consultation with the gun industry. But on its face, the "critical machining" test seems pretty subjective, if not inscrutable. Barrett noted that it "doesn't appear in the statute" and "seems a little made up." She suggested it is "just sort of a way of allowing for a de minimis exception."

The previous standard also overlaps to some extent with the "readily converted" test, since both consider how much time is required to transform a product into a functional frame or receiver. "Over five decades," Prelogar argued, the ATF "has always looked at whether a partially complete frame or receiver can be brought to functional condition quickly, easily, and efficiently."

In general, Patterson got more pushback from the justices than Prelogar did, and it came from Republican as well as Democratic appointees.

"What is the purpose of selling a receiver without the holes drilled in it?" Chief Justice John Roberts wondered. Just as "some individuals enjoy…working on their car every weekend," Patterson replied, others "want to construct their own firearm." Roberts was skeptical: "Drilling a hole or two, I would think, doesn't give the same sort of reward that you get from working on your car on the weekends."

Justice Brett Kavanaugh told Prelogar "your statutory interpretation has force," although he expressed concern that people might be prosecuted even when they did not realize they were breaking the law as the ATF is now reading it. Under the licensing and serial number provisions, Prelogar said, the government would have to prove "willfulness," which is "an important check against criminal prosecutions that might be unwarranted."

Prelogar conceded that someone could be prosecuted for failing to conduct a newly required background check even if he was not aware of that requirement. "Is that something the government would do?" Kavanaugh asked. "I don't think the government would be likely to charge someone in that kind of situation," Prelogar replied. Kavanaugh seemed satisfied by her assurances.