Supreme Court tosses Mexico’s $10 billion lawsuit accusing U.S. gunmakers of fueling cartel war

The Supreme Court on Thursday tossed out a $10 billion lawsuit Mexico filed against top firearm manufacturers in the U.S. that claimed the companies’ business practices were helping fuel cartel violence plaguing the country.

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...