The U.S. Supreme Court unanimously ruled on Thursday to dismiss a lawsuit filed by the Mexican government against two American firearms companies, ending a high-profile legal effort to hold U.S. manufacturers accountable for gun violence linked to cross-border trafficking. The 9-0 decision, written by Justice Elena Kagan, overturned a lower court ruling that had allowed the case to proceed, finding that the companies were protected under U.S. law.

Mexico had accused gunmaker Smith & Wesson and distributor Interstate Arms of knowingly enabling illegal arms sales that ultimately armed drug cartels, fueling widespread violence. However, the justices concluded that Mexico’s allegations did not demonstrate the companies actively assisted in criminal activity. Instead, the court said the accusations amounted to “indifference,” which does not meet the legal threshold for aiding and abetting under the 2005 Protection of Lawful Commerce in Arms Act.

This federal law shields gun manufacturers and sellers from liability when their products are misused in criminal acts, and the court affirmed that Mexico’s claims failed to bypass these protections. While acknowledging that U.S. firms may be aware of some guns ending up in the hands of traffickers, the ruling emphasized that mere awareness is not sufficient to prove legal complicity in wrongdoing.

The lawsuit, originally filed in 2021 in a Boston federal court, aimed to hold the gun companies accountable for the flow of weapons into Mexico, where strict gun control laws exist. Mexico alleged the firms designed and marketed firearms in ways appealing to criminal groups and maintained sales channels involving dealers who knowingly supplied straw purchasers — intermediaries who illegally resell to traffickers.

Despite the Supreme Court's decision, Mexico has pledged to continue its legal campaign. A senior official at Mexico’s Foreign Ministry, Pablo Arrocha Olabuenaga, expressed disappointment but reiterated confidence in the country's legal position and the international support it has received. He stressed that Mexico remains determined to pursue justice over the costs it bears from U.S.-linked gun violence.

In its case, Mexico had sought financial compensation and a court order requiring changes in the companies’ sales and marketing practices. The government argued that U.S.-sourced firearms are responsible for a large portion of gun crimes in Mexico, costing the country over $250 million annually and burdening public services such as healthcare and law enforcement.

Critics of the ruling, including international affairs expert Carlos Perez Ricart, condemned the outcome as yet another example of how U.S. gun laws shield the industry from accountability. He pointed to the human toll of trafficked weapons in Mexico and denounced what he described as Washington’s legal impunity in the face of cross-border violence.