No Legislative actcontrary to the Constitution, can be valid. To deny this, would be to affirm, that the deputy is greater than his principal; that the servant is above his master; that the Representatives of the People are superior to the People themselvesCourts were designed to be an intermediate body between the People and the Legislature, in order, among other things, to keep the latter within the limits assigned to their authority. The interpretation of the laws is the proper and peculiar province of the Courts. A Constitution is, in fact, and must be regarded by the Judges, as a fundamental law. It therefore belongs to them to ascertain its meaning, as well as the meaning of any particular Act proceeding from the Legislative body. If there should happen to be an irreconcilable variance between the twothe Constitution ought to be preferred to the statute, the intention of the People to the intention of their agents. Nor does this conclusion by any means suppose a superiority of the Judicial to the Legislative power. It only supposes that the power of the People is superior to both; and that where the will of the Legislature, declared in its statutes, stands in opposition to that of the People, declared in the Constitution, the Judges ought to be governed by the latter rather than the former. They ought to regulate their decisions by the fundamental laws, rather than by those which are not fundamental. [...] whenever a particular statute contravenes the Constitution, it will be the duty of the Judicial tribunals to adhere to the latter and disregard the former.
Alexander Hamilton