The U.S. Supreme Court has declined to consider challenges to a pair of state laws restricting the use of confinement in animal agriculture.

The court was asked to hear arguments that the California and Massachusetts laws improperly interfered with interstate commerce, but in both cases Justice Clarence Thomas was the lone vote in favor of considering the cases.

Both laws sought to end certain animal confinement practices such as using cages in egg production. But the measures also sought to restrict the sale of products using the practices no matter their point of origin. This led to challenges from other states seeking to sell their ag products to California and Massachusetts consumers.

Missouri Attorney General Eric Schmitt said he was “disappointed that the U.S. Supreme Court declined to hear this case” and pledged to “continue to fight for Missouri consumers and farmers and protect them from burdensome regulations.” Missouri was the lead plaintiff in the California case. 

The office of the attorney general of Indiana - the lead plaintiff in the Massachusetts case - did not respond to a request for comment.

Kitty Block, acting president and CEO of the Humane Society of the United States, welcomed the decision, saying voters in California and Massachusetts were properly seeking to enforce “animal welfare standards for products sold within their states.”

“Courts have long held that states have the right under the Constitution to establish similar criteria,” she said in a statement. “But some factory farming corporations hate the progress we’ve made in this area, and have spent years prevaricating and delaying instead of making reforms."

California’s law was originally passed in 2008, updated in 2010 and took effect in 2015. The Massachusetts law is set to take effect in 2022. A similar measure — Proposition 12 — was approved by California voters this year.

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