The US District Court for the Western District of Missouri Central Division Tuesday ruled that a Missouri law attempting to invalidate federal firearm laws within the state is unconstitutional. Specifically, Judge Brian C. Wimes ruled that the Missouri Second Amendment Preservation Act (SAPA) violates the Supremacy Clause of the US Constitution and the doctrine of intergovernmental immunity.

In Wimes’ opinion and order, the court ruled that SAPA is “unconstitutional in its entirety.” The court ruled that SAPA violates the Supremacy Clause because it tries to invalidate federal law. The Supremacy Clause states that federal law takes precedence over state laws and prohibits states from interfering with the federal government’s exercise of its constitutional powers. Additionally, the court ruled that the law violates the doctrine of intergovernmental immunity by impeding the operations of constitutionally enacted federal laws. These federal laws are the National Firearms Act and the Gun Control Act. Under the doctrine, state legislatures cannot invalidate or disregard federal statutes.

Missouri Governor Michael L. Parson signed SAPA into law in June 2021. The law declares certain federal gun laws “invalid” if no Missouri state-level equivalent exists. In addition, SAPA carries a fine of $50,000 for each attempt to enforce such federal gun laws. In response to the passing of SAPA, the US DOJ sued to challenge its constitutionality.

The defendants of the case have appealed Wimes’ decision to the US Court of Appeals for the Eighth Circuit.