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3D-Printed Guns, Untraceable Firearms, and Domestic Violent Extremist Actors

3D-Printed Guns, Untraceable Firearms, and Domestic Violent Extremist Actors
7th January 2021 Jonathan Lewis
In Insights

While uncertainty surrounding the COVID-19 pandemic continues to fuel a massive increase in domestic gun sales, a supporter of the boogaloo movement was charged in November in one of the first known cases of domestic extremists mass-producing and illicitly selling 3D-printed firearms components.

In an indictment filed in West Virginia, Timothy Watson was accused of illegally manufacturing and selling 3D-printed plastic components of automatic rifles through his now-defunct website, Through this front company, Watson purported to sell “3D printed innocuous hooks,” which were actually designed to convert a legal semi-automatic rifle into a fully automatic machinegun. According to the indictment, the simple, two-piece detachable wall hangers were intended to function as a drop in auto sear, defined by the Bureau of Alcohol, Tobacco, and Firearms (ATF) as a combination of parts intended to convert a weapon to “shoot automatically more than one shot, without manual reloading, by a single function of the trigger.”

The government claims that Watson knowingly manufactured, advertised and sold these illegal, 3D-printed “drop in auto sears” to domestic anti-government extremists, specifically members of the boogaloo movement. Since the start of 2020, members of the boogaloo movement have made national headlines as a loose coalition of accelerationist anti-government actors, with at least 21 self-described members arrested and numerous alleged violent plots disrupted. Through online advertising in boogaloo-themed Facebook pages and coded language in communications with customers and on his website, Watson is alleged to have signaled that he was an “adherent of the Boogaloo movement” who was selling firearms components.

His arrest is a sign of not only the interconnected and online nature of this violent, anti-government movement, but also the demand for illegal, untraceable, 3D-printed firearms and firearm components. Watson’s business is alleged to have made over 600 individual transactions and 362 unique shipments to addresses in 46 states from January to October 2020. Furthermore, the criminal complaint details the links between Watson’s ‘portable wall hangers’ business and numerous alleged domestic terrorists self-aligned with the boogaloo movement.

Watson’s business transaction logs on PayPal show a January 2020 purchase of a drop in auto sear by Steven Carrillo, a member of the boogaloo movement accused of shooting two Federal Protective Service officers in Oakland, California, in May as well as two additional law enforcement officers during his arrest in June. The government further alleges that Watson’s 3D-printed firearm components were at the center of the prosecution of two boogaloo movement members in Minneapolis, Minnesota, for their attempted provision of material support to Hamas. These individuals were accused of manufacturing and selling homemade suppressors to individuals they believed were members of the designated foreign terrorist organisation. Watson’s criminal complaint details that a cooperating defendant in the Minneapolis case positively identified the “drop in auto sear that he ordered from” When one of the boogaloo movement members pleaded guilty in December, he admitted that the pair also delivered a 3D-printed drop in auto sear to the purported members of Hamas, and that they subsequently placed an order for additional auto sears.

While Watson’s case is one of the first known instances of a domestic violent extremist utilising 3D-printed firearm components, ‘ghost guns’ (homemade or unserialised firearms) have been recognised as a systemic problem in need of more effective and nuanced policy responses. 3D printing—in both the case of homemade untraceable firearms and the manufacture of firearms components as in the Watson case—is simply the latest technological innovation that allows extremists to more effectively and efficiently obtain and use untraceable firearms. In many cases, these individuals would otherwise be prohibited from lawful firearm possession under 18 U.S.C. § 922, a popular prosecutorial tool for law enforcement in domestic terrorism cases in the absence of any federal domestic terrorism statute.

While homemade, unserialised firearms have long been a popular hobby for a range of gun enthusiasts, the technological spike in DIY gunsmithing has allowed even those with minimal technical understanding of firearms to construct unregulated “80% lower receivers” – metal parts which “lack just a few slots and cavities and thus don’t legally qualify as frames until those parts are manually drilled or milled out.” Because the current ATF standards do not consider these 80% kits as firearms, any gun enthusiast or violent extremist is currently able to order such a kit and produce a functional, unserialised and unregistered firearm in their home within a matter of hours. While the current ATF definitions related to 80% lowers are the subject of several ongoing lawsuits, the weak federal regulatory system and legislative inaction in the face of the rising prevalence of unserialised and untraceable firearms have allowed for the relatively simple acquisition or construction of a so-called ‘ghost gun’.

Despite early opposition, the federal government has failed to respond forcefully to the prevalence of the 3D printer as an avenue for unregistered firearms. After Defense Distributed released the blueprint for the first functional fully 3D-printed gun in 2013, the online publication of a number of their Computer Aided Design (CAD) files was  prohibited by the Department of State. Their letter to Defense Distributed noted that the technical data of these CAD files fall within the United States Munitions List (USML), making them subject to regulation by the Department of State. As such, they argued, the CAD files for these “controlled defense articles” including an anti-tank warhead, were unlawful to export without prior authorisation. In response, Defense Distributed sued the government, which led to a series of judicial opinions, settlements, and injunctions that have ensured the legality of these files remains in flux to this day.

A government settlement in 2018 involving a modification to the USML was followed quickly by a lawsuit by state attorneys general and an injunction invalidating the settlement. In January 2020, the Trump administration attempted the transferal of some authority over small arms exports from the Department of State to the Commerce Department, which led to a second state lawsuit and a second injunction. The status of these CAD files is currently in judicial limbo pending new executive branch guidance from the incoming Biden-Harris administration, which has signalled its desire to “ensure the State Department continues to block the code used to 3D print firearms from being made available on the Internet.”

While several states have since implemented legislation banning a range of unserialised guns, gun kits, and 3D-printed firearms components, the absence of effective and robust action from the federal government to combat free proliferation of unserialised firearms and growing accessibility DIY gunsmithing effectively ensures that the era of the 3D-printed gun is already here. DEFCAD, an online repository of files for 3D-printed firearm components, includes in its featured files both an AR-15 printable lower receiver and an AR-15 80% milling jig—which allows for the manual completion of an unfinished 80% lower receiver. Each has tens of thousands of views and hundreds of unique downloads, and regardless of future judicial or legislative action to prevent further dissemination of such technical data, the removal of all such content from the Internet seems fanciful.

Within the narrow context of domestic extremism, the nascent boogaloo movement is far from alone in their pursuit of untraceable automatic weapons. In the past year, court records from ongoing prosecution of members of both The Base and Atomwaffen Division have detailed the widespread and pervasive interest in the manufacture of unregistered and untraceable firearms by racially and ethnically violent extremists within the United States. Atomwaffen Division member Kaleb Cole was the subject of an Extreme Risk Protection Order that sought the removal of all firearms in his possession, with reports suggesting Cole was constructing ghost guns, including potentially 3D-printed lower receivers. Meanwhile in Maryland, members of the Base reportedly constructed a ghost gun by combining stock metal components with the unserialised, 3D-printed versions of controlled, regulated parts. The online and decentralised nature of post-organisational extremism in the United States further complicates law enforcement efforts to prevent extremist acquisition of illegal firearms, including 3D-printed firearms and components.

The position of 3D-printed firearms at the intersection of technological innovation and firearms invariably means that, as with much else within the field of extremism, it is not solely an American problem. As experts at the Council of Foreign Relations noted in the aftermath of the Halle Synagogue Shooting, “we are likely to face a growing danger from homemade and 3-D-printed firearms and their creators.” The use of untraceable, homemade weapons with 3-D printed components by the attacker supports original reporting on the increased popularity of illegal 3D-printed firearms in Europe. Furthermore, any legal outcome regarding Defense Distributed’s CAD files will likely have far-reaching impacts: the federal government’s original opposition to their online publication noted that, “The State Department is particularly concerned that [Defense Distributed’s] proposed export of undetectable firearms technology could be used in an assassination, for the manufacture of spare parts by embargoed nations, terrorist groups, or guerrilla groups, or to compromise aviation security overseas in a manner specifically directed at U.S. persons.”

The case of Timothy Watson is emblematic of the challenges extremist innovation poses to the modern domestic counterterrorism apparatus. Research on the boogaloo movement online has shown that “communication platforms have created hospitable environments, giving the movement a place to grow, recruit, and organise.” The existing challenges surrounding the free acquisition of untraceable, unregistered firearms by bad actors are compounded by the innately decentralised nature of the boogaloo movement and numerous violent extremist groups within the United States. Moving forward, domestic violent extremists, as well as racially and ethnically motivated violent extremists, appear well-positioned to take advantage of the increasingly DIY nature of gunsmithing and 3D printing in their firearms acquisition efforts.

Jonathan Lewis is a Research Fellow at the Program on Extremism, where he studies extremist organisations in the United States and activities of the Islamic State and its supporters in the United States and Europe. He is an Investigator with the National Counterterrorism Innovation, Technology, and Education Center (NCITE), and provides assistance for The ISIS Files Project as well as for PoE’s partnership with the Global Network on Extremism and Technology (GNET). Jonathan also provides support for PoE’s partners in the Congressional Counter-Terrorism Caucus, the leading bipartisan voice in Congress for pragmatic approaches to tackling extremism and radicalisation.