Gun-control lawyer Jonathan Lowy argued to the Supreme Court that some AR-15s bought in the United States and later used by Mexican cartels should count against Second Amendment protection for millions of American owners of the same rifles. His group Global Action on Gun Violence filed an amicus brief backing assault-weapon bans and later restated the claim in a Substack column. The brief treats U.S. sales totals as inflated by straw buys for foreign criminal groups and cites 250,000 to 1 million firearms trafficked to Mexico each year, though those figures cover all guns rather than only the rifles at issue. Sharyl Attkisson reported that the Mexican government was the leading purchaser of U.S. guns later traced to Mexican crime scenes from 2016 to 2023. The Supreme Court has already held in Heller that heavy criminal use of handguns does not cancel their protection for lawful self-defense, and Bruen bars judges from balancing claimed safety gains against the right.