The U.S. Supreme Court unanimously ruled that the Federal Meat Inspection Act preempts a California law requiring that any animal unable to walk be euthanized immediately upon arrival at a packing plant without the opportunity for veterinary evaluation.

The ruling reverses a Ninth Circuit decision that vacated a 2009 injunction by a U.S. District Court in California. The injunction stemmed from a case brought in December 2008 by the National Meat Association. The American Meat Institute (AMI) was an intervenor in the case.  The plaintiffs argued that the state could not impose requirements that are different from, or in addition to, those required by federal law. Federal law permits federal veterinarians on site in packing plants to determine whether or not non-ambulatory pigs are healthy and fit for consumption.

“Federal law precludes California’s effort to impose new rules, beyond any the Food Safety Inspection Service (FSIS) has chosen to adopt, on what a slaughterhouse must do with a pig that becomes non-ambulatory during the production process,” says Justice Elena Kagan, who wrote the court’s unanimous opinion.

“We are pleased that the Supreme Court has affirmed the significant preemption authority in the Federal Meat Inspection Act,” says AMI President J. Patrick Boyle. “This is a legal principle that is essential to an industry like ours that is among the most heavily regulated and inspected industries in the nation.”

The full ruling is available here.