The California prop measure includes banning the sale of pork from pigs that are kept in tightly confined spaces.
The justices voted 5-4 to uphold a lower court’s decision to dismiss a lawsuit filed by the National Pork Producers Council and the American Farm Bureau that sought to invalidate the law.
The groups argued that the measure violated a U.S. constitutional provision called the Commerce Clause that courts say gives the federal government the power to regulate interstate commerce, not the states themselves.
“While the Constitution addresses many weighty issues, the type of pork chops California merchants may sell is not on that list,” wrote conservative Justice Neil Gorsuch, who authored the Court’s main opinion.
Prop 12 was approved by California voters in 2018.
It bans in-state sales of pork, veal, and eggs from animals whose confinements didn’t meet space requirements.