By: Allison Wong ‘27
Volume XI – Issue I – Fall 2025
I. BACKGROUND
From 1998 to 1999, over 30 U.S. cities and counties filed suit against firearm manufacturers and dealers. [1] The complaints alleged industry practices fueled illegal gun trafficking, placing an undue burden on municipalities in addressing violent crime. First, manufacturers focused innovation efforts on concealability and lethality, while failing to design weapons with feasible safety mechanisms. Second, dealers used porous distribution methods accessible to illegal gun traffickers in criminal markets. Third, industry advertising marketed powerful assault weapons as necessary for basic self-defense, appealing to broader consumer bases. [2] As a result of gun violence, municipalities experienced rising law enforcement and hospital treatment costs, in addition to public safety concerns. [3] In 1998, federal law-enforcement data indicated that nearly half of firearms involved in crime had been purchased from federally-licensed dealers within the previous three years. [4] The rapid movement of firearms from manufacturer to dealer to criminal suggested a more direct relationship between the industry and gun violence.
As these suits proceeded, the National Rifle Association (NRA) and firearms industry lobbied Congress for protection against liability. [5] Congress passed the Protection of Lawful Commerce in Arms Act (“PLCAA”), signed into law by President George W. Bush on October 26, 2005. [6] The PLCAA generally shields licensed firearm and ammunition manufacturers and dealers from civil liability action seeking damages for harm resulting from third-party unlawful or criminal misuse of their products. [7] The PLCAA effectively dismissed the majority of pending city and county lawsuits, while enhancing U.S. firearm manufacturer and dealer protection against future suits.
On August 4, 2021, the Mexican government sued major U.S. gun manufacturers Smith & Wesson Brands, Inc., Barrett Firearms Manufacturing, Inc., Beretta U.S.A. Corp., Colt’s Manufacturing Company LLC, Glock Inc., and wholesaler Interstate Arms. [8] The complaint alleged commercial practices contributed to firearm trafficking into Mexico, fueling violent crime. Although the Mexican Department of Defense sets strict restrictions on the sale of domestic firearms, thousands of guns are smuggled into the country annually by drug cartels and other criminals. [9] The Mexican Ministry of Foreign Affairs estimated that seventy percent of firearms trafficked into Mexico originated in the U.S., with over 17,000 homicides in 2019 linked to trafficked weapons. [10] In the complaint, the Mexican government sought at least ten billion dollars in compensation, estimating the damage caused by gun violence to equal nearly two percent of the country’s 2021 gross domestic product of 1.3 trillion dollars. [11]
Petitioners contended that actions taken by Smith & Wesson Brands et al. fell within the aiding and abetting exception to PLCAA immunity, initiating the first foreign government lawsuit against U.S. gun manufacturers. [12] The U.S. District Court dismissed the action, but the First Circuit U.S. Court of Appeals reversed, ruling in favor of the initial complaint. [13] On October 4, 2024, the U.S. Supreme Court granted certiorari, considering in Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos (2025) whether U.S. gun manufacturers can be held liable for violent crime in Mexico under the PLCAA based on domestic production and sale of firearms later distributed and trafficked to Mexican cartels. [14]
II. PREDICATE EXCEPTION
PLCAA provisions are codified in U.S. Code Title 15, “Commerce and Trade,” Chapter 105, “Protection of Lawful Commerce in Arms.” [15] It establishes that a qualified civil liability action may not be brought in any federal or state court, defining qualification as a civil action against a U.S. gun manufacturer or dealer based on third-party criminal or unlawful misuse of a firearm. [16] The PLCAA predicate exception, however, removes immunity when the manufacturer or dealer knowingly violated a state or federal statute regarding firearm sale and the violation proximately caused harm for which the complaint seeks relief. [17] The predicate exception may apply when a gun manufacturer or dealer aids and abets another person in making a false statement about the legality of a sale or engages in criminal sale. [18] Additionally, the exception covers gun manufacturers that aid and abet in committing a federal gun crime.
Federal aiding and abetting law is codified in U.S. Code Title 18, “Crimes and Criminal Procedure,” Part II, “Criminal Procedure.” [19] An individual may be responsible for a crime they have not personally carried out if they deliberately help another commit it. To aid and abet a crime, an individual must take an affirmative act in furtherance of the offense and intend to facilitate its result. [20] In United States v. Peoni (1938), the Second Circuit U.S. Court of Appeals specified the standard for mens rea. In Peoni, the defendant sold counterfeit bills to an individual Regno, who subsequently sold them to another individual Dorsey. [21] When Dorsey tried to pass the bills, Peoni was charged as an accessory. The Court reversed Peoni’s conviction, holding that mere knowledge of the crime was insufficient to constitute aiding and abetting—there must be purposeful or specific intent to facilitate it. [22] In applying this standard, the Court considers precedent set by Direct Sales Co. v. United States (1943) and Twitter, Inc. v. Taamneh (2023). [23] Taken together, these cases illustrate the distinction between general awareness of potential third-party misuse of a product or service and purposeful, substantial aiding and abetting.
In Direct Sales, the Court held a mail-order drug manufacturer and wholesaler liable for aiding and abetting a physician’s illegal narcotics scheme. [24] Petitioner violated the Harrison Narcotics Tax Act of 1914, a federal law regulating the production and distribution of opiates to control non-medical substance use. [25] First, Petitioner sold the physician a quantity of morphine sulfate far exceeding that of legitimate medical use. The physician received roughly five to six thousand half-grain tablets each month whereas the average customer received only four hundred quarter-grain tablets each year. [26] Second, Petitioner offered special discounts and bulk purchase options to the physician, despite warnings from the Bureau of Narcotics against such practices. [27] The drug manufacturer and wholesaler, therefore, demonstrated specific intent to cooperate with the physician’s illegal drug distribution. Petitioner was not engaging in passive sales with mere knowledge of potential third-party wrongdoing, but rather tailoring products and services to further the physician’s illegal activity, meeting the aiding and abetting standard. [28]
In Twitter, the Court rejected a claim that social-media companies Twitter, Facebook, and Google aided and abetted a terrorist attack carried out by Abdulkadir Masharipov on behalf of the Islamic State of Iraq and Syria (ISIS). [29] The initial complaint alleged, first, that ISIS used the platforms to carry out organization recruitment and fundraising, with social-media algorithms recommending the content to other users. Second, the companies were aware of this activity but failed to intervene by either restricting ISISaffiliated users or removing the organization’s posted content. The Court, however, held that such allegations failed to state a claim under the U.S. Antiterrorism Act of 1992, a federal law allowing U.S. nationals injured by an international terrorist act to bring suit in federal court. [30] Companies in Twitter provided social media platforms intended for general public use; they experienced third-party misuse of their product and service, but did not actively engage in the facilitation or execution of the crime itself. There lacked distinction in how the companies treated ISIS-affiliated users and any member of the general public, making their connection to the crime too remote and general to infer conscious participation. [31]
The Court’s decision in Twitter established three key principles of aiding and abetting. First, aiding and abetting is most applicable to specific wrongful acts. In establishing liability for a more general category of misconduct, an individual must engage in pervasive, systemic, and culpable participation in the furtherance and execution of the crime. [32] Second, aiding and abetting relies on misfeasance, not nonfeasance. [33] An individual cannot be held liable for failure to act absent an independent duty to take such action. Third, the products and services arising from general and routine activities that have the potential to, incidentally, assist in the commission of a crime are likely insufficient to constitute aiding and abetting. [34] The manufacturer or dealer’s mere knowledge that a fraction of the products or services they offer may be subjected to criminal misuse does not constitute liability for it.
III. MAJORITY APPLICATION
In Smith & Wesson Brands, the Mexican government centered its complaint on three allegations. [35] First, U.S. gun manufacturers sold firearms to dealers who they knew illegally brought them to Mexican gun traffickers. Second, dealers failed to impose controls and regulations on how their distribution networks functioned to prevent such transactions from occuring. Third, U.S. gun manufacturers made particular design and advertising choices geared towards Mexican cartels to stimulate demand for their products. On June 5, 2025, the U.S. Supreme Court decided Smith & Wesson Brands in favor of the petitioners. [36] In a unanimous decision, the Court held that because Mexico’s complaint did not plausibly allege that the defendant gun manufacturers aided and abetted gun dealers’ unlawful sales of firearms to Mexican traffickers, PLCAA bars the lawsuit. The majority opinion, authored by Justice Elena Kagan, argued that accepting Mexico’s theory would undermine PLCAA’s core protections. [37]
Regarding the first allegation, the Court in Twitter established that aiding and abetting is most commonly applied to specific acts of criminal misconduct. In Smith & Wesson Brands, however, the Mexican government chose not to articulate particular sales, transactions, or partnerships that U.S. gun manufacturers allegedly engaged in. [38] Liability for a broader category of misconduct, as decided in Twitter, must then demonstrate pervasive, systemic, and culpable participation. Unlike in Direct Sales, where narcotics were sold from the drug manufacturer and dealer in a manner particular to the physician carrying out illegal activity, the U.S. gun manufacturers in Smith & Wesson Brands were supplying firearms indiscriminately to particular traffickers, cartels, or criminals. Even if such specialized business transactions did exist, where U.S. gun manufacturers favored a consumer base engaged in unlawful conduct, the Court holds that the complaint fails to identify this specific rogue actor or dealer. [39]
Second, U.S. gun manufacturers have the option to impose stricter requirements on firearm sales, but they can only lower the probability of criminal misconduct. The Court held that manufacturer failure to impose controls on dealer practices, therefore, does not constitute aiding and abetting liability. [40] In Twitter, the Court established that aiding and abetting relies upon misfeasance, not nonfeasance. The passive inaction or omission of controls and regulations implemented by U.S. gun manufacturers fails to constitute active engagement in the commission of a crime. Manufacturers do not have an independent duty to control the use of firearms at the end of the supply chain, when they are in the hands of drug cartels or at the precipice of initiating violence. [41] The facts in Smith & Wesson Brands are more similar to those of Twitter, where social media platforms lacked an independent duty to enact stricter regulations on ISIS-affiliated content compared to general public users, than those of Direct Sales, where the drug manufacturer and dealer had an independent duty under the Harrison Narcotics Tax Act and Bureau of Narcotics law enforcement warnings to control dosage and quantity of opiate sales. Gun manufacturers displayed nonfeasance, or lack of action, exemplified by lack of regulation imposed in Twitter rather than misfeasance, or improper conduct, exemplified by targeted transactions used in Direct Sales. While it may be preferable for U.S. gun manufacturers to lower the probability of criminal misconduct, their failure to enact the controls and regulations that would do so does not meet the aiding and abetting standard.
Third, allegations about design and advertising choices fail to constitute aiding and abetting. The Court argued that military-style assault weapons are widely legal and purchased by ordinary consumers, not just traffickers and cartel members. [42] U.S. gun manufacturers cannot be held liable simply because Mexican cartel members decide they prefer to use this type of weapon. Furthermore, the Court held that while use of Spanish-language names or graphics alluding to aspects or figures of Mexican history may appeal to cartel members engaging in gun violence, they may also appeal to a broader consumer base of millions of law-abiding Hispanic Americans. [43] Rather than the special discounts and deals the drug manufacturer and dealer was offering the particular physician in Direct Sales, the manufacturer choices in Smith & Wesson Brands more closely resemble the general platform and algorithm offered by companies in Twitter, of which a fraction of users could potentially use to engage in unlawful activity. This fractional potential is insufficient to establish liability under the third principle articulated by the Court in Twitter. [44]
IV. BROADER IMPLICATIONS
Overall, the Court’s decision in Smith & Wesson Brands significantly strengthens PLCAA provisions, reinforcing the protection of firearm manufacturers from liability. It rejects alleged responsibility of U.S. companies for downstream criminal acts that occur in other countries, potentially setting precedent that shields other industries from liability for third-party misuse of their products or services. In adopting a relatively narrow approach, however, the Court has chosen not to establish a brightline test for aiding and abetting in firearm industry cases. Furthermore, the Court has chosen not to impose regulations on the firearms industry and dictate U.S. gun manufacturer choices.
Justice Clarence Thomas, concurring, emphasized the need for additional clarity regarding aiding and abetting legal violations. Under aiding and abetting, there must be active participation in the commission of a crime, insinuating that a crime must have been committed for the defendant to have furthered its completion. [45] In previous cases, such as Direct Sales and Twitter, the crimes of illegal narcotics schemes and terrorist activity, respectively, were established before suits proceeded against the drug or social media companies. In contrast, there lacked established misconduct in Smith & Wesson Brands other than the general threat of violent crime in Mexico. A question remains as to whether a formal conviction is required rather than an allegation of misconduct to begin an aiding and abetting evaluation in the first place. [46] If plaintiffs can rely on mere allegations of criminal misconduct under the PLCAA predicate exception, defendants will then be litigating criminal guilt in a civil proceeding. PLCAA-related litigation can then be weaponized into de facto collateral adjudication of criminal guilt, without the higher constitutional protections afforded in criminal proceedings. [47]
Justice Ketanji Brown Jackson, concurring, elaborated on two aspects of the Court’s decision. First, that Mexico’s failure to specify the details of PLCAA statutory violation was the element fatal to their claim. [48] U.S. gun manufacturers may be liable for gun trafficking to bad actors if they engaged in specific, targeted transactions similar to those in Direct Sales. The complaint, however, alleged a broader category of liability without providing these details. Second, allowing this lawsuit from the Mexican government would contradict Congress’s intent to preserve legislative, not judicial control over gun regulation. [49] In other words, it is not up to the Court to decide how the firearms industry needs to be regulated. Instead, the Court intends to apply PLCAA provisions as they stand, rather than impose specific requirements over firearm design, marketing, and supply chain choices.
Endnotes
[1] Siebel, Brian J. "City Lawsuits Against the Gun Industry: A Roadmap for Reforming Gun Industry Misconduct." Saint Louis University Public Law Review 18, no. 1 (1999): 248. https://scholarship.law.slu.edu/plr/vol18/iss1/12.
[2] Siebel, “City Lawsuits Against the Gun Industry,” 249.
[3] Siebel, “City Lawsuits Against the Gun Industry,” 252.
[4] Butterfield, Fox. "New Data Point Blame at Gun Makers." The New York Times, November 28, 1998. https://www.nytimes.com/1998/11/28/us/new-data-point-blame-at-gun-makers.html.
[5] Stolberg, Sheryl G. "Congress Passes New Legal Shield for Gun Industry." The New York Times, October 21, 2005. https://www.nytimes.com/2005/10/21/politics/congress-passes-new-legal-shield-for-gun-industry.html.
[6] Congress.gov. "Text - S.397 - 109th Congress (2005-2006): Protection of Lawful Commerce in Arms Act." October 26, 2005. https://www.congress.gov/bill/109th-congress/senate-bill/397/text.
[7] Cohen, Jordan B., and Dave S. Sidhu. "The Protection of Lawful Commerce in Arms Act: The Supreme Court Recognizes Statutory Immunity for Firearm Companies in Case Brought by the Government of Mexico." Congress.gov, September 19, 2025. https://www.congress.gov/crs-product/R48715.
[8] "Mexico Sues U.S. Gun Manufacturers For Contributing To Arms Trafficking Deaths." NPR, August 5, 2021. https://www.npr.org/2021/08/05/1025011396/mexico-sues-u-s-gun-manufacturers-for-contributing-to-armstrafficking-deaths.
[9] NPR, “Mexico Sues U.S. Gun Manufacturers.”
[10] NPR, “Mexico Sues U.S. Gun Manufacturers.”
[11] NPR, “Mexico Sues U.S. Gun Manufacturers.”
[12] Cohen and Sidhu, "The Protection of Lawful Commerce in Arms Act."
[13] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[14] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[15] 15 U.S.C. §§7901–7903.
[16] 15 U.S.C. §7903(5)(A).
[17] 15 U.S.C. §7903(5)(A)(iii).
[18] 15 U.S.C. §7903(5)(A)(iii)(I)-(II).
[19] 18 U.S.C. §2.
[20] 18 U.S.C. §2.
[21] United States v. Peoni, 100 F.2d 401 (2d Cir. 1938).
[22] United States v. Peoni, 100 F.2d 401 (2d Cir. 1938).
[23] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[24] Direct Sales Co. v. United States, 319 U.S. 703 (1943).
[25] Courtwright, David. "Preventing and Treating Narcotic Addiction: A Century of Federal Drug Control." The New England Journal of Medicine 373, no. 22 (November 26, 2015): 2095-97. https://doi.org/10.1056/NEJMp1508818.
[26] Direct Sales Co. v. United States, 319 U.S. 703 (1943).
[27] Direct Sales Co. v. United States, 319 U.S. 703 (1943).
[28] Direct Sales Co. v. United States, 319 U.S. 703 (1943).
[29] Twitter, Inc. v. Taamneh, 598 U.S. (2023).
[30] Twitter, Inc. v. Taamneh, 598 U.S. (2023).
[31] Twitter, Inc. v. Taamneh, 598 U.S. (2023).
[32] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[33] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[34] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[35] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[36] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[37] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[38] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[39] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[40] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[41] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[42] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[43] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[44] Twitter, Inc. v. Taamneh, 598 U.S. (2023).
[45] 18 U.S.C. §2.
[46] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[47] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[48] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).
[49] Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. (2025).