In a victory for the firearm industry, the unanimous ruling tossed out the case under a U.S. law that largely shields gunmakers from liability when their firearms are used in crime.

Congress passed the law two decades ago to halt a flurry of lawsuits against gunmakers that were similar to the case Mexico filed, Justice Elena Kagan wrote. Her opinion overturned a lower court order that let the suit go forward because the companies themselves were accused of violating the law.

Kagan wrote that Mexico’s lawsuit made no plausible argument that the companies had knowingly helped gun trafficking into the country.

“It does not pinpoint, as most aiding-and-abetting claims do, any specific criminal transactions that the defendants (allegedly) assisted,” Kagan wrote.

Mexico’s Ministry of Foreign Affairs said it strongly disagreed with the decision and would continue its fight against firearm trafficking. “Mexico has presented solid arguments demonstrating the harm that arms manufacturing companies cause to our country,” it said in a statement.

Mexican President Claudia Sheinbaum pointed to a second suit the country filed in 2022 against five gun shops and distributors in Arizona. “We’re going to see what the result is, and we’ll let you know,” she said.

Mexico has strict gun laws and has just one store where people can legally buy firearms. But thousands of guns are smuggled in by the country’s powerful drug cartels every year.

The Mexican government says at least 70% of those weapons come from the United States. The lawsuit claimed that companies knew weapons were being sold to traffickers who smuggled them into Mexico and decided to cash in on that market.

The Mexican government first filed its blockbuster suit in 2021 against some of the biggest gun companies, including Smith & Wesson, Beretta, Colt and Glock.

The companies have long rejected Mexico’s allegations, arguing the country came can’t show they’re responsible for a relatively few people using their products to commit violence. “We are gratified that the Supreme Court agreed that we are not legally responsible for criminals misusing that product to hurt people, much less smuggling it to Mexico to be used by drug cartels,” said attorney Noel Francisco, who represented Smith & Wesson.

The trade group National Shooting Sports Foundation also applauded the ruling, adding that gunmakers work with U.S. authorities to prevent gun trafficking. “This is a tremendous victory for the firearm industry and the rule of law,” said Lawrence Keane, senior vice president and general counsel.

A federal judge originally tossed out the lawsuit under the 2005 Protection of Lawful Commerce in Arms Act, but the First U.S. Circuit Court of Appeals in Boston revived it under an exception for cases that allege companies engaged in illegal business practices.

That exception has come up in other cases, including in lawsuits stemming from mass shootings.

Families of victims of the 2012 mass shooting at Sandy Hook Elementary School in Newtown, Connecticut, for example, argued it applied to their lawsuit because the gunmaker had violated state law in the marketing of the AR-15 rifle used in the shooting, in which 20 first graders and six educators were killed.

The families eventually secured a landmark $73 million settlement with Remington, the maker of the rifle.

The Supreme Court’s ruling doesn’t appear to foreclose those cases, said David Pucino, legal director at the Giffords Law Center to Prevent Gun Violence. “All survivors, in the United States, in Mexico, and anywhere else, deserve their day in court, and we will continue to support them in their fight for justice,” he said.