The acceptance of this principle in the United States may be dated from the decision by the Supreme Court in 1803 of the case of Marbury v. Madison.1 This point is of such transcendent importance that the argument of Marshall will be given in extenso.

"The question whether an act, repugnant to the Constitution, can become the law of the land," says the great Chief Justice, " is a question deeply interesting to the United States; but, happily, not of an intricacy proportioned to its interest. It seems only necessary to recognize certain principles, supposed to have been long and well established, to decide it. That the people have an original right to establish, for their future government, such principles, as, in their opinion, shall most conduce to their own happiness is the basis on which the whole American fabric has been erected. The exercise of this original right is a very great exertion; nor can it, nor ought it, to be frequently repeated. The principles, therefore, so established, are deemed fundamental. And as the authority from which they proceed is supreme, and can seldom act, they are designed to be permanent. This original and supreme will organizes the government, and assigns to different departments their respective powers. It may either stop here, or establish certain limits not to be transcended by those departments. The government of the United States is of the latter description. The powers of the legislature are defined and limited; and that those limits may not be mistaken, or forgotten, the Constitution is written. . . . It is a proposition too plain to be contested, that the Constitution controls any legislative act repugnant to it; or, that the legislature may alter the Constitution by an ordinary act. Between these alternatives there is no middle ground. The Constitution is either a supreme paramount law, unchangeable by ordinary means, or it is on a level with ordinary legislative acts, and, like other acts, is alterable when the legislature shall please to alter it. . . . Certainly all those who have framed written constitutions contemplate them as forming the fundamental and paramount law of the nation, and, consequently, the theory of every such government must be that an act of the legislature repugnant to the Constitution is void. . . . If an act of the legislature repugnant to the Constitution is void, does it, notwithstanding its invalidity, bind the courts and oblige them to give it effect? ... It is emphatically the province and duty of the judicial department to say what the law is. . . . So if a law be in opposition to the Constitution; if both the law and the Constitution apply to a particular case, so that the court must either decide that case conformably to the law, disregarding the Constitution; or conformably to the Constitution, disregarding the law; the court must determine which of these conflicting rules governs the case. This is of the very essence of judicial duty. If, then, the courts are to regard the Constitution, and the Constitution is superior to any ordinary act of the legislature, the Constitution, and not such ordinary act, must govern the case to which they both apply."

11 Cr. 137; 2 L. ed. 60.

The reasoning of Webster and Kent as to the invalidity of legislative acts contrary to the Constitution, and as to the power of the court to declare them such, is substantially the same as that of Marshall.2