While the Constitution thus confers on the legislative bodies the complete power of legislation in all cases, it proceeds, in the spirit of justice, to provide for the protection of the responsibility of the President.  It does not compel him to affix the signature of approval to any bill unless it actually have his approbation; for while it requires him to sign if he approve, it, in my judgment, imposes upon him the duty of withholding his signature if he do not approve.  In the execution of his official duty in this respect he is not to perform a mere mechanical part, but is to decide and act according to conscientious convictions of the rightfulness or wrongfulness of the proposed law.  In a matter as to which he is doubtful in his own mind he may well defer to the majority of the two Houses.  Individual members of the respective Houses, owing to the nature, variety, and amount of business pending, must necessarily rely for their guidance in many, perhaps most, cases, when the matters involved are not of popular interest, upon the investigation of appropriate committees, or, it may be, that of a single member, whose attention has been particularly directed to the subject.  For similar reasons, but even to a greater extent, from the number and variety of subjects daily urged upon his attention, the President naturally relies much upon the investigation had and the results arrived at by the two Houses, and hence those results, in large classes of cases, constitute the basis upon which his approval rests.  The President’s responsibility is to the whole people of the United States, as that of a Senator is to the people of a particular State, that of a Representative to the people of a State or district; and it may be safely assumed that he will not resort to the clearly defined and limited power of arresting legislation and calling for reconsideration of any measure except in obedience to requirements of duty.  When, however, he entertains a decisive and fixed conclusion, not merely of the unconstitutionality, but of the impropriety, or injustice in other respects, of any measure, if he declare that he approves it he is false to his oath, and he deliberately disregards his constitutional obligations.

I cheerfully recognize the weight of authority which attaches to the action of a majority of the two Houses.  But in this case, as in some others, the framers of our Constitution, for wise considerations of public good, provided that nothing less than a two-thirds vote of one or both of the Houses of Congress shall become effective to bind the coordinate departments of the Government, the people, and the several States.  If there be anything of seeming invidiousness in the official right thus conferred on the President, it is in appearance only, for the same right of approving or disapproving a bill, according to each one’s own judgment, is conferred on every member of the Senate and of the House of Representatives.