“It is emphatically the province and duty of the judicial department to say what the law is,” Chief Justice John Marshall famously wrote in Marbury v. Madison (1803). “The constitution controls any legislative act repugnant to it.”
This bold assertion of authority – the U.S. Constitution itself contains no wording on who is empowered to decide that an act is repugnant – established that the Supreme Court has the final word on which laws run afoul of the founding document. (Incidentally, the ruling represents a classic example of begging the question. Justice Marshall essentially said, “That’s just how it is.”) Afterward, as the nation took shape and without much ado, state courts adopted or assumed the same stance with respect to state laws and constitutions.
