A Missouri law declaring some federal gun regulations “invalid” is unconstitutional because it violates the U.S. Constitution’s supremacy clause, a federal appeals court in St. Louis unanimously ruled on Monday. 

A three-judge panel of the Eighth Circuit Court of Appeals agreed with a district court ruling from last year that blocked Missouri from enforcing the Second Amendment Preservation Act, a law passed in 2021 that penalizes police for enforcing certain federal gun laws.

Among the law’s provisions is a $50,000 fine for law enforcement agencies that“infringe” on Missourians’ Second Amendment rights.

Some of the gun regulations deemed invalid by the law include imposing certain taxes on firearms, requiring gun owners to register their weapons and laws prohibiting “law-abiding” residents from possessing or transferring their guns.

“Because the (Second Amendment Preservation) Act purports to invalidate federal law in violation of the Supremacy Clause, we affirm the (district court’s) judgment,” Chief Judge Steven Colloton, a George W. Bush appointee, wrote in the unanimous opinion. 

The U.S. Department of Justice filed the lawsuit challenging the law arguing it has undermined federal drug and weapons investigations. Late last year, the U.S. Supreme Court denied a request by Attorney General Andrew Bailey to allow Missouri to enforce the Second Amendment Preservation Act while its appeal is ongoing.

In a statement through his spokeswoman, Bailey said he is reviewing the decision. He added: “I will always fight for Missourians’ Second Amendment rights.”

Kansas City Mayor Quinton Lucas released a statement Monday afternoon praising the court’s decision. 

“Two years ago, Missouri enacted an unconstitutional law, claiming to invalidate federal gun laws,” Lucas wrote. “The law was rejected in federal appeals court today… I am saddened that our state expended the time and energy of many in our legal system in service of this clearly unconstitutional effort.”