The fact that Congress has given a particular construction to a constitutional provision, is of very great weight with the Supreme Court when it is called upon to examine the correctness of this interpretation. This is due to the fact that the court is dealing with the act of a separate and independent department of government which the Constitution intends to be, so far as possible, co-ordinate in power with the executive and judicial departments, that is, co-ordinate in the sense that, like them, when acting within the limits of the power constitutionally granted it, it shall be independent of control by the others.

From necessity the Constitution must have intended that the legislative and executive departments should have the power, in the first instance at least, of determining the extent of the powers constitutionally granted to them, and that, therefore, the judiciary should not substitute its judgment for theirs except in cases where there is no doubt that the action which has been taken is not constitutionally warranted.

"A decent respect for a co-ordinate branch of the Federal Government/' says Justice Strong in Knox v. Lee,16 "demands that the- judiciary should presume, until the contrary is clearly shown, that there has been no transgression of power by Congress, all the members of which act under the obligation of an oath of fidelity to the Constitution."

And in the Sinking Fund Cases17 Chief Justice Waite says: "The declaration [that an act of Congress is void] should never be made except in a clear case. Every possible presumption is in favor of the validity of a statute and this continues until the contrary is shown beyond a rational doubt."

In Ogden v. Saunders18 Justice Washington says: "It is but a decent respect due to the . . . legislative body, by which any law is passed, to presume in favor of its validity, until the violation of the Constitution is proved beyond all reasonable doubt."

16 12-Wan. 457; 20 L. ed. 287. 17 99 U. S. 700; 25 L. ed. 406. 1812 Wh. 213; 6 L. ed. 606.

Quotations similar to those given might be multiplied, all in substance stating this general rule, declared by the Supreme Court from the first years of its existence, that an act of Congress, with reference to its constitutionality, is to receive the benefit of every reasonable doubt.19

19 This principle of construction has received a most philosophical examination in the essay of Professor Thayer, entitled The Origin and Scope of the American Doctrine of Constitutional Law, and from this source the substance of the immediately following paragraphs are taken.

In giving to a legislative interpretation the benefit of every rational doubt as to its constitutionality, the court in effect says, that it does not attempt to say what its own best judgment is as to the point at issue, but whether it is within the limits of reason for the legislature to give to the Constitution the construction it has given. The case is thus quite similar to the function of a judge when called upon to set aside the verdict of a jury, or of a jury when passing upon the question of self-defense in a criminal trial, or of negligence in an action of tort, or the responsibility of an inferior for acts done at the order of a superior. "The doctrine," says Thayer, "... is this, that in dealing with the legislative action of a co-ordinate department, a court cannot always, and for the purpose of all sorts of questions, say that there is but one right and permissible way of construing the Constitution. When a court is interpreting a writing merely to ascertain or apply its true meaning, then, indeed, there is but one meaning allowable; namely, that which the court adjudges to be its true meaning. But when the ultimate question is not that, but whether certain acts of another department, officer, or individual are legal or permissible, then this is not true. In the class of cases which we have been considering, the ultimate question is not what is the true meaning of the Constitution, but whether legislation is sustainable or not."

Again, Thayer says: " The courts have perceived with more or less distinctness that this exercise of the judicial function does in truth go far beyond the simple business which its judges sometimes describe. If their duty were in truth merely and nakedly to ascertain the meaning of the text of the Constitution and of the impeached act of the legislature, and to determine as an academic question, whether in the court's judgment the two were in conflict, it would, to be sure, be an elevated and important office, one dealing with great matters, involving large public considerations, but yet a function far simpler than it really is. Having ascertained all this, yet there remains a question - the really momentous question - whether, after all, the court can disregard the act. It cannot do this as a mere matter of course - merely because it is concluded that upon a just and true con-! ruction. the law is unconstitutional. ... It can only disregard the act when those who have