As President Donald Trump pressures Mexico to address the flow of migrants and drugs heading north into the United States, the Supreme Court is set to hear arguments Tuesday in a major appeal about one thing that’s crossing the border toward Mexico: guns.

U.S. firearms maker Smith & Wesson and distributor Interstate Arms have appealed a lower court's ruling that the lawsuit could proceed on the grounds that Mexico has plausibly alleged that the companies aided and abetted illegal gun sales,

While President Donald Trump has made a point of going after drug cartels, the Mexican government says U.S. gunmakers should be held liable for violence caused by their weapons in Mexico.