Missouri Attorney General Josh Hawley announced that 12 states have joined Missouri in a lawsuit challenging a California law requiring any eggs sold in the state to come from hens that have space to stretch out in their cages. The lawsuit was filed on December 4 to the U.S. Supreme Court.

In 2008, Californians approved, by a 63% vote, the Prevention of Farm Animal Cruelty Act, which requires that chickens and certain other animals be able to turn around freely, lie down, stand up, and fully extend their limbs. The act became effective in 2015. After California egg farmers complained that they would be at a competitive disadvantage with farmers in other states, the law was expanded in 2010 to ban the sale of eggs from any hens that weren’t raised in compliance with California’s standards (Los Angeles Times).

Missouri and several other states previously filed suit challenging the California law but, in 2016, the Ninth Circuit Court of Appeals ruled that they lacked standing to pursue their claims. The Dec. 4 lawsuit claims that California’s regulations violate both a federal law prohibiting states from imposing their own standards on eggs produced in other states, and the Commerce Clause of the U.S. Constitution, which gives Congress exclusive authority to regulate commerce among and between states, explains Hawley in a press release. He added that the suit includes an economic analysis with new data estimating California’s egg law has cost consumers nationwide up to $350 million annually due to higher egg prices.

The 12 states that joined Missouri in filing the current lawsuit are: Alabama, Arkansas, Indiana, Iowa, Louisiana, Nebraska, Nevada, North Dakota, Oklahoma, Texas, Utah, and Wisconsin.