Who should decide the disputed meaning of laws and regulations in American democracy: legislatures, courts, or executive branch agencies? Chevron deference is a long-standing Supreme Court standard that federal agencies with expertise in a specific area must be given deference if federal law is unclear. Auer deference adds that federal agencies should have that power when they interpret their own regulations. These doctrines have been questioned in recent years as violations of the separation of powers. Kisor provides guidance on who defines the meaning of regulations and the balance of power between federal agencies and courts.