WASHINGTON — The Supreme Court on Thursday rejected a lawsuit by the Mexican government against U.S. gun manufacturers that attempted to hold them responsible for drug cartel violence.

In a unanimous decision written by Justice Elena Kagan, the court held that U.S. legislation that shields gunmakers from liability in certain cases barred the lawsuit. Mexico, she wrote, had not plausibly argued that American gun manufacturers had aided and abetted gun dealers’ unlawful sales to Mexican drug traffickers.

Mexico had claimed that the gun industry’s production and sale of arms in the United States helped fuel and supply drug cartels, harming the Mexican government. Mexican government lawyers also claimed the companies were aware that some of their guns were illegally trafficked and that the c

See Full Page