US Supreme Court Rules on Case Involving Gun Kits That Readily Convert into Working Firearms
April 6, 2025 - Posted by Larry E. Holtz, Esq.
In Bondi v. Vanderstok (U.S. 3/26/2025), the United States Supreme Court upheld the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) rule treating ghost guns as deadly firearms. Ghost guns are unserialized, untraceable firearms that can be easily put together in minutes from parts acquired without a background check.
The federal Gun Control Act, 18 U.S.C. § 921(a)(3) (GCA) defines a “firearm” to include “(A) 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; (B) the frame or receiver of any such weapon; (C) any firearm muffler or firearm silencer; or (D) any destructive device.”
As explained by Justice Gorsuch in Vanderstok, we have recently “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.”
“These kits vary widely both in how complete they come and in how much work is required to finish them. At one end of the spectrum, a kit may lack essential parts and ‘require substantial effort, specialized expertise, uncommon equipment, and a significant amount of time’ before anyone can fire a shot. … At the other end, some kits ‘contain all components necessary’ for ‘a complete pistol’ and can be completed in perhaps half an hour using commonly available tools.”
Sales of these kits have grown exponentially. While home hobbyists enjoy assembling them, so do criminals. “That is largely due to how the kits are sold. Some manufacturers and dealers take the position that weapon parts kits do not qualify as ‘firearms’ subject to the GCA. As a result, they say, they are free to sell their products without obtaining a federal license, conducting background checks, maintaining sales records, or marking components with serial numbers.” This has resulted in police departments around the Nation being confronted with an explosion of crimes involving these “ghost guns.”
In 2022, the Bureau of Alcohol, Tobacco, Firearms and Explosives adopted a new rule designed to combat the proliferation of ghost guns. One provision addresses weapon parts kits that are “designed to or may readily be completed, assembled, restored, or otherwise converted to expel a projectile by the action of an explosive.” Another relevant aspect of the agency’s new rule concerns a “key building block of almost any firearm: its frame or receiver.” Under subsection (B) of §921(a)(3), “the frame or receiver of any such weapon” covered by subsection (A) is itself treated as a “firearm.” Effectively, “that means a frame or receiver is, even when sold separately, subject to the Act’s requirements.”
“In its 2022 rule, ATF sought to expand this definition. Now, the agency said, a “frame or receiver” subject to subsection (B) of §921(a)(3), should be understood to encompass as well “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 frame or receiver.” See 27 C.F.R. §478.12(c).
To decide this case, the court considered a Polymer80’s “Buy Build Shoot” kit, which comes with all of the necessary components to build a Glock-variant semiautomatic pistol. “And it is so easy to assemble that, in an ATF test, an individual who had never before encountered the kit was able to produce a gun from it in 21 minutes using only ‘common’ tools and instructions found in publicly available YouTube videos.”
The first picture below shows the kit; the second depicts the gun the kit yields.
The Supreme Court held that the Gun Control act “embraces, and thus permits ATF to regulate, some weapon parts kits and unfinished frames or receivers. Accordingly, the regulation, 27 C.F.R. § 478.11 is valid under 18 U.S.C. § 921(a)(3)(A) as the term “weapon” includes some unfinished instruments of combat that could be readily converted into a working firearm. Moreover, 27 C.F.R. § 478.12(c) is not inconsistent with 18 U.S.C. § 921(a)(3)(B) as that statute permits the Bureau of Alcohol, Tobacco, and Firearms to regulate at least some partially complete frames or receivers.
