The day before National Pig Day, which is on March 1st, those visiting Hirsch Fruit Farm could meet small and large pigs from Flo Acre Farms.
Washington D.C. – The Supreme Court on Monday declined to hear a second challenge to California’s Proposition 12, the state’s landmark animal welfare law that bars the sale of pork from pigs raised in confined spaces. The decision leaves in place a 2018 voter-approved measure that has transformed pork production standards far beyond the state’s borders and ignited an ongoing legal and political debate over the limits of state power in the national economy.
At the heart of the case is a question older than California’s law itself: how far a single state can go in regulating the goods sold within its borders when those goods are mostly produced elsewhere. With California consuming roughly 13% of the nation’s pork but producing very little of its own, out-of-state producers have argued that the law effectively forces them to adopt California’s standards nationwide.
The justices offered no explanation for declining the case, a standard practice when turning away petitions. Justice Brett Kavanaugh noted that he would have granted review, but he did not elaborate on his reasoning. Two years ago, the court issued a narrow 5–4 decision upholding Proposition 12 in a separate challenge, but the fractured nature of that ruling left room for legal maneuvering. The Iowa Pork Producers Association had hoped this latest case would reopen the door.
Proposition 12 requires that pork sold in California must come from breeding pigs housed in at least 24 square feet of space. Iowa producers, who lead the nation in pork production, contended the rule amounts to economic discrimination. Their petition centered on the difference in lead time provided to in-state and out-of-state producers: six years versus six weeks.
California pushed back, noting that the earlier compliance window applied to a different set of in-state regulations and arguing that the law applies equally to all producers, regardless of geography. “Proposition 12 enacts a neutral sales restriction that treats in-state and out-of-state farmers the same,” the state wrote in its filings.
The legal argument hinges on the Constitution’s dormant Commerce Clause, a doctrine that prevents states from imposing rules that unduly burden interstate commerce. The earlier lawsuit, brought by national pork industry groups, avoided this specific claim—an omission that the Iowa producers sought to rectify in their challenge.
But the court’s refusal to revisit the issue reinforces the legal status quo: states may impose standards on goods sold within their borders, even if those rules reverberate nationwide.
As Justice Neil Gorsuch put it in the court’s 2023 ruling: “While the Constitution addresses many weighty issues, the type of pork chops California merchants may sell is not on that list.”
