The bottom line
In Bondi v. VanDerStok, the Supreme Court voted 7-2 to let the ATF’s frame or receiver rule stand, effectively giving unelected bureaucrats the power to redefine what a firearm is without any act of Congress. Justices Thomas and Alito were the only two willing to hold the line. This decision is a disaster for gun owners and for constitutional governance, and the implications reach far beyond parts kits.
Attribution from Bearing Freedom. Watch the original video. Commentary, not legal advice.
What the ATF actually did
On March 26, 2025, the Supreme Court issued its opinion in Bondi v. VanDerStok — formerly Garland v. VanDerStok before the attorney general changed — upholding the ATF’s 2022 frame or receiver rule by a 7-2 margin. Justice Neil Gorsuch wrote for the majority. Justices Clarence Thomas and Samuel Alito dissented separately. I’ll get to those dissents in a moment, because they’re the most important thing about this case.
First, let’s be precise about what this rule actually does, because the media’s framing of it as a “ghost gun regulation” is designed to make you think this is about criminals. It isn’t.
The ATF’s rule — Final Rule 2021R-05F, “Definition of ‘Frame or Receiver’ and Identification of Firearms” — expanded the statutory definition of “firearm” under the Gun Control Act of 1968. Under the original law, a firearm is a weapon that expels a projectile by the action of an explosive, or its frame or receiver. That definition requires a functional item. The ATF’s rule changed that to include partially completed frames or receivers and weapon parts kits that are “designed to or may readily be completed, assembled, restored, or converted” to function as a firearm.
Think carefully about what that language actually means. It does not say “a firearm.” It says “designed to or may readily be converted.” That is not the same thing. A block of aluminum that a skilled machinist could turn into a receiver in a few hours could, under a loose reading of that language, qualify. The ATF is not regulating firearms. It is regulating potential.
Why Gorsuch got it wrong
Justice Gorsuch’s majority opinion rests on what has been called the “artifact nouns” theory. He analogized an unfinished weapon parts kit to an unfinished manuscript that might still be called a “novel.” His reasoning was that Congress intended the word “weapon” to include items capable of ready conversion, and that the ATF’s rule was at minimum facially consistent with that reading.
The majority also leaned heavily on the facial challenge standard from United States v. Salerno, which holds that a facial challenge to a law or regulation fails unless the challenger proves that the law is unconstitutional in every possible application. Because some parts kits — specifically the sort of all-in-one “Buy Build Shoot” pistol kit that takes 20 minutes and common tools to assemble — arguably do fall within a broad reading of “readily converted,” the majority concluded the rule was not facially invalid, even if individual applications of it might be.
This is a move that will be used to insulate bad agency rules from constitutional challenge for decades. Justice Alito said it directly in his dissent: applying the Salerno standard to Administrative Procedure Act challenges means plaintiffs will “always lose,” because an agency can write a rule that sweeps up clearly regulated items alongside clearly unconstitutional ones, and the facial challenge fails because of the clearly regulated subset. Alito called this “a huge boon for the administrative state.” He was right.
Justice Thomas went to the text. A weapons parts kit “is not a weapon until it is converted into an operable gun,” he wrote, noting that the statutory definition of “firearm” requires a frame or receiver — precisely the component that an unfinished parts kit does not have. Thomas argued the majority was not interpreting the statute; it was rewriting it.
Both of them are correct. And both of them were outvoted 7-2.
The registry problem hiding in plain sight
People keep asking why the government is so desperate to regulate parts kits and unfinished receivers. The gun control lobby talks about crime. But let me tell you what this is actually about.
When you buy a firearm from a licensed dealer, there is a Form 4473 in a bound book somewhere. There is a record. If the dealer goes out of business, those records go to the ATF. If law enforcement submits a trace request, the ATF can follow the chain of commercial transfers and often find a name at the end. The system is not a registry in the formal sense — federal law actually prohibits the creation of a comprehensive registry — but it functions like one for the vast majority of commercially purchased firearms.
A firearm you make yourself has none of that. There is no Form 4473. There is no dealer. If you manufacture a firearm for your own personal use, you are not currently required to serialize it. That has been true for all of American history. There were no restrictions on the personal manufacture of arms for private use during the 17th, 18th, or 19th centuries. The colonial gunsmiths who supplied the Continental Army worked in a world where self-made arms were an assumed part of life.
The ATF’s rule, by defining parts kits and unfinished receivers as “firearms,” forces their manufacturers to serialize them and mark them before sale, and it requires buyers to undergo background checks. That cuts the government into every transaction. The result is that the one category of firearm that existed entirely outside the quasi-registry system — the home-built gun — is now being absorbed into it.
Ghost guns — privately made firearms, to use the accurate term — represent about 3.2% of all firearms traced in connection with crimes between 2017 and 2023, according to ATF data. Even in peak years, the number is under 6% of traces. This is not a crime wave. This is a pretext.
What “readily converted” actually means in practice
The vagueness of the “readily converted” standard is not an accident. It is a feature.
If you are a skilled machinist, you can convert a piece of raw aluminum into a firearm frame. If you own the right equipment, you can convert a polymer blank into a functional receiver. The rule does not define “readily” with any precision. Gorsuch acknowledged in the majority opinion that some products might be “so incomplete or cumbersome to assemble that they cannot fairly be described as weapons capable of ready conversion,” but he left that question for future as-applied challenges.
What this means in practice is that the scope of the rule is genuinely unlimited in the near term. The ATF gets to decide on a case-by-case basis what it considers “readily converted,” and every legal challenge has to start from scratch as an as-applied challenge rather than invalidating the rule entirely. This is an enormous amount of discretion vested in an agency whose entire history on Second Amendment questions has been one of maximum expansion of regulatory authority.
Seven justices and what it tells you
The 7-2 split matters. It is not just the vote count. It tells you something about the ideological composition of the court as it applies to gun rights specifically.
Thomas and Alito are constitutional originalists in the truest sense. They look at the text, they look at the history, and they apply the law. The other Republican-appointed justices — Roberts, Gorsuch, Kavanaugh, and Barrett — are often described as conservative, and on many issues they are. But their conservatism frequently takes the form of deference to institutional authority and reluctance to strike down government action broadly. Gorsuch writing the majority opinion should not surprise anyone who paid attention to his jurisprudence on administrative law more generally; he authored the opinion overruling Chevron deference in Loper Bright last year, but that was a structural administrative law question. On gun rights specifically, his instinct is to find a way to let the government win on the narrowest possible grounds.
Kavanaugh and Barrett are even more telling. Both were confirmed as reliably pro-Second Amendment voices. Both joined Gorsuch’s opinion without writing separately to note any concern. If you were expecting Bruen’s text-history-tradition framework to do work here, it didn’t. The majority did not even engage with the Second Amendment question. The case was decided purely as a statutory interpretation and administrative law matter.
What comes next
The facial challenge is over. The rule stands. That doesn’t mean the fight is finished.
As-applied challenges are still available. If the ATF tries to extend this rule to products that are genuinely raw materials — items that require significant skill, time, or equipment to become functional firearms — a narrower challenge has a better chance under the space Gorsuch left open. The Firearms Policy Coalition, which brought the original challenge alongside co-plaintiff Jennison, has already signaled it will continue litigation.
What I won’t do is pretend this is anything other than a serious loss. The Supreme Court just told the ATF that it can redefine the objects it regulates without Congress passing a new law, as long as it can find some applications of its rule that are at least arguably within existing statutory language. That is a precedent that will be used again. The next ATF, under the next administration that wants to restrict guns, will cite VanDerStok when it writes its next rule.
Thomas and Alito saw this clearly. The other five did not. And that is a problem that will not be fixed by anything short of changing who sits on that court — or changing the composition of an agency that has been allowed for decades to treat the Second Amendment as an obstacle to be managed rather than a right to be protected.
Attribution from Bearing Freedom. Watch the original video. Commentary, not legal advice.
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