who can decide whether a law is unconstitutional the supreme court congress the states the president
Nullification (U.S. Constitution) Courts at the state and federal level, including the U.S. Supreme Court, repeatedly have rejected the theory of nullification.[2] The courts have decided that under the Supremacy Clause of the Constitution, federal law is superior to state law, and that under Article III of the Constitution, the federal judiciary has the final power to interpret the Constitution. Therefore, the power to make final decisions about the constitutionality of federal laws lies with the federal courts, not the states, and the states do not have the power to nullify federal laws.