Cross-Border Liability: Examining Mexico's Lawsuit against U.S. Gun Manufacturers
As Ieva Jusionyte remarked in her book Exit Wounds, which examined gun trafficking from the U.S. to Mexico, “Waging this war [cartel warfare] required weapons that were not for sale in Mexico.” Mexico has one of the highest rates of firearm mortality, with more than 160,000 people being killed by firearms between 2015 and 2022. Even more surprisingly, Mexico only has one gun store, which begs the question: where are these guns coming from? Data on guns recovered and traced from crime scenes provide a clear answer: the United States. As the Mexican government struggles to combat the cartel and gun violence in their country, they have turned to pursuing legal action against the source of these guns as a potential remedy.
On March 4th, 2025, the Supreme Court heard the case Smith & Wesson Brands, Inc. v.
Estados Unidos Mexicanos, in which the Mexican government is suing seven American gun manufacturers for “illegally aiding and abetting illegal firearm sales to gun traffickers”. The Mexican government’s lawsuit alleges that these seven gun manufacturers utilized “straw purchasers” to illegally facilitate the trafficking of guns into Mexico; guns that were later used to fuel violence all across the country. The Mexican government is seeking $10 billion to cover the costs of this violence.
According to the ATF, straw purchasers are “individuals who purchase a gun for someone who is prohibited by law from possessing one, or for someone who does not want his or her name associated with the transaction”,. Straw purchases are punishable by up to 10 years in prison and an additional fine of up to $250,000. The Mexican government is alleging that straw purchases were conducted in the United States with help from major US gun manufacturers. These guns were then allegedly trafficked across the US-Mexico border.
The issue before the court, however, is whether there is any validity to these claims, or if they are barred by a federal statute called the Protection of Lawful Commerce in Arms Act (PLCAA). PLCAA essentially gives immunity to gun manufacturers for harm their guns could cause. However, it is important to note that the law provides for several exceptions, one of which enables a victim to take legal action against a gun manufacturer who knowingly violated a State or Federal statute applicable to the sale or marketing of the gun, and if that violation was a proximate cause of the harm for which one is seeking relief. As a result, the question becomes whether or not these gun manufacturers (1) knowingly aided and abetted these straw purchases, and (2) if those purchases can be considered to proximate cause (meaning a cause that is legally sufficient to support liability) for the injuries Mexico is alleging.
Notably, this case has reached the Supreme Court through the appeal of the gun manufacturer's motion to dismiss. The Mexican government has simply filed a complaint that outlines their grievances, but because a motion to dismiss had been filed, no discovery in which both parties were required to come together to present evidence and exchange information has occurred. This has created a hurdle for the Mexican government, as they have not been able to come forward with extensive evidence to support their claims in court. Nevertheless, the First Circuit Court of Appeals did rule in favor of the Mexican government, finding that Mexico’s suit against U.S. gun manufacturers can proceed , as their “claims are statutorily exempt from the protections PLCAA provides” based on the limited evidence they were permitted to provide. The decision was promptly appealed by the US gun manufacturers.
The Mexican government presents several arguments in their Writ of Certiorari in opposition to the gun manufacturers’ appeal. They argue that the First Circuit Court’s decision does not in fact split with the decisions of other courts on similar matters, as the other cases cited had key differences from Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, and all of them predated PLCAA. Furthermore, they assert that the First Circuit Court’s ruling was correct in establishing proximate cause because, “proximate cause demands some direct relation between the injury asserted and the injurious conduct alleged,” and they found that most of Mexico’s claims are substantiated by sufficient evidence to prove direct relation between the purchasing of firearms and cartel gun violence. For example, they found that the cost of increased law enforcement was a direct injury stemming from the illegal trafficking of guns into Mexico.
Furthermore, the attorneys for the Mexican government cite the case Twitter, Inc. v. Taamneh, claiming that the precedent established reaffirmed aiding and abetting liability as “the defendant having given knowing and substantial assistance to the primary tortfeasor”; they continue to assert that the First Circuit Court was correct in finding that the Mexican government sufficiently alleged that the gun manufacturers knowingly facilitated the illegal sale of firearms. Finally, the Mexican government asserts that the case should at least be allowed to go through the discovery process, in order to examine and evaluate necessary evidence and permit the case to be tried on its merits. For these reasons, the Mexican government urged the Supreme Court to rule against the gun manufacturers’ motion to dismiss the case.
The attorneys for the gun manufacturers present alternatives to the Mexican government’s claims, asserting that the First Circuit Court’s decision was incorrect and must be reviewed. They claim that the proximate cause ruling of the court is faulty and presents a schism with previously established federal court precedent. Attorneys for the gun manufacturers claim the Mexican government’s case relies on a line of causation that is too muddled and indirect, thus creating a situation in which the apportionment of damages would be impossible. Furthermore, they questioned the whole nature of the injuries Mexico is claiming, these “injuries” are actually derivative of injuries suffered by others (like the victims of the drug cartels), and therefore not valid.
They also claim that the First Circuit Court’s ruling on the aiding and abetting liability question is incorrect, again citing Twitter, Inc. v. Taamneh. The gun manufacturers' attorneys argue that Twitter affirmed the need for the party being sued to have committed an “affirmative act with the intent of facilitating the offense’s commission”, and that Mexico’s allegations do not satisfy this requirement. They further emphasize that the questions this case poses are of utmost importance, because they are integral to a discussion of industry liability that could greatly alter business in the U.S., and because they concern national sovereignty, as a foreign entity is attempting to regulate an American industry out of their own self-interest. The petitioners continue to assert that it is ideal to have the case heard without discovery, as it concerns only the bare bones and logic of the case, asking two “clean” legal questions without being muddled by the “lengthy factual record that would follow any trial”.
Supreme Court Justices seemed relatively skeptical of the Mexican government’s argument. Justice Kavanaugh noted that “lots of sellers and manufacturers of ordinary products know that they're going to be misused by some subset of people” and that a ruling supporting the right of legal action against them could have “destructive effects” on the U.S. economy. Justice Gorsuch and Justice Kagan also voiced skepticism, questioning whether or not gun manufacturers had actually aided and abetted violations of gun laws, and if they did, who exactly were they aiding and abetting? Justice Jackson also noted that the Mexican government’s complaint lacks specifics about the U.S. laws that were violated by the manufacturers, and that the manipulation of this ambiguity could be what Congress was trying to shield against with PLCAA.While a decision for this case will not be arrived at until this summer, it seems unlikely that the Supreme Court will uphold the First Circuit Court’s ruling. U.S. gun manufacturers will likely remain protected, once again.
Alice Kovarik is a first-year studying Economics and International and Public Affairs. She can be reached at alice_kovarik@brown.edu.
Yani Ince is a senior concentrating in History and Political Science. She is a blog editor for the Brown Undergraduate Law Review and can be reached at ianthe_ince@brown.edu.