UPDATE 1-Gun makers urge US Supreme Court to hear appeal in Mexico's lawsuit

(Adds industry group's comment in paragraph 12)

By Nate Raymond

April 19 (Reuters) - U.S. gun manufacturers on Thursday asked the U.S. Supreme Court to hear their challenge to Mexico's $10 billion lawsuit seeking to hold them responsible for facilitating the trafficking of firearms to violent drug cartels across the U.S.-Mexico border.

Eight companies including Smith & Wesson Brands and Sturm, Ruger & Co in a petition argued that a lower court wrongly concluded the case qualified for an exception to a U.S. law that grants the firearms industry broad protection from lawsuits over the misuse of their products.

A trial court judge had dismissed the case citing that law, the Protection of Lawful Commerce in Arms Act. But the Boston-based 1st U.S. Circuit Court of Appeals in January concluded Mexico's claims fit within the narrow exception to the liability shield.

The 1st Circuit did so after finding that Mexico had plausibly alleged the business practices of the seven gun makers and one distributor it had sued aided and abetted the illegal trafficking of guns to Mexico.

The companies on Thursday told the 6-3 conservative majority U.S. Supreme Court that the 1st Circuit's ruling defied the high court's past precedents and should never have been allowed to move forward.

"Mexico's suit has no business in an American court," their lawyers wrote.

The companies argued that without the U.S. Supreme Court's intervention, the U.S. firearms industry would face years of costly litigation by a "foreign sovereign that is trying to bully the industry into adopting a host of gun-control measures that have been repeatedly rejected by American voters."

Alejandro Celorio, legal adviser to Mexico's foreign ministry, wrote on the social media platform X that the county would "follow up on this request and will be ready in case the Supreme Court decides to admit the matter for study."

In its lawsuit filed in 2021, Mexico alleged the companies undermined its strict gun laws by designing, marketing and distributing military-style assault weapons in ways they knew would arm drug cartels, fueling murders, extortions and kidnappings in the country.

Mexico says over 500,000 guns are trafficked annually from the U.S. into Mexico, of which more than 68% are made by the companies it sued.

Mexico said the smuggling has contributed to high rates of gun-related deaths, declining investment and economic activity and a need for it to spend more on law enforcement and public safety.

The companies deny wrongdoing. "These legal and heavily regulated products are lawfully made and sold," Lawrence Keane, the general counsel of the industry trade group the National Shooting Sports Foundation, said in a statement. (Reporting by Nate Raymond in Boston; Additional reporting by Valentine Hilaire in Mexico City; Editing by Lisa Shumaker and Ros Russell)