Article 1, Section 8, Clause 18
St. George Tucker, Blackstone's Commentaries 1:App. 286--901803
After the satisfactory exposition of this article given in the Federalist, that if the constitution had been silent on this head, there could be no doubt, that all the particular powers requisite, as the proper means of executing the general powers specified in the constitution, would have resulted to the federal government, by unavoidable implication; and that if there be any thing exceptionable in this particular clause, it must be sought for in the specific powers, upon which this general declaration is predicated: and after the explicit declaration contained in the twelfth article of the amendments to the constitution, that the powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people: we might have indulged a reasonable hope, that this clause would neither have continued to afford any ground of alarm, and apprehension, on the part of the people, or the individual states, nor any pretext for an assumption of any power not specified in the constitution, on the part of the federal government. But, notwithstanding this remarkable security against misconstruction, a design has been indicated to expound these phrases in the constitution, so as to destroy the effect of the particular enumeration of powers, by which it explains and limits them, which must have fallen under the observation of those who have attended to the course of public transactions.
The plain import of this clause is, that congress shall have all the incidental or instrumental powers, necessary and proper for carrying into execution all the express powers; whether they be vested in the government of the United States, more collectively, or in the several departments, or officers thereof. It neither enlarges any power specifically granted, nor is it a grant of new powers to congress, but merely a declaration, for the removal of all uncertainty, that the means of carrying into execution those otherwise granted, are included in the grant. A single example may illustrate this matter. The executive has power to make treaties, and by the treaty with Algiers, a certain tribute is to be paid annually to that regency. But the executive have no power to levy a tax for the payment of this tribute; congress, therefore, are authorised by this clause, to pass a law for that purpose: without which the treaty, although it be a supreme law of the land, in it's nature, and therefore binding upon congress, could not be executed with good faith. For the constitution expressly prohibits drawing any money from the treasury but in consequence of appropriations made by law.
Whenever, therefore, a question arises concerning the constitutionality of a particular power; the first question is, whether the power be expressed in the constitution? If it be, the question is decided. If it be not expressed, the next enquiry must be, whether it is properly an incident to an express power, and necessary to it's execution. If it be, it may be exercised by congress. If it be not, congress cannot exercise it. . . . And this construction of the words "necessary and proper," is not only consonant with that which prevailed during the discussions and ratifications of the constitution, but is absolutely necessary to maintain their consistency with the peculiar character of the government, as possessed of particular and defined powers, only; not of the general and indefinite powers vested in ordinary governments.
Under this construction of the clause in question, it is calculated to operate as a powerful and immediate check upon the proceedings of the federal legislature, itself, so long as the sanction of an oath, and the obligations of conscience, are regarded, among men. For, as every member is bound by oath to support the constitution, if he were to bring every measure that is proposed to the test here mentioned, and reject whatsoever could not stand the scrutiny, we should probably cease to hear any questions respecting the constitutionality of the acts of the federal government. To which we may add, that this interpretation of the clause is indispensably necessary to support that principle of the constitution, which regards the judicial exposition of that instrument, as the bulwark provided against undue extension of the legislative power. If it be understood that the powers implied in the specified powers, have an immediate and appropriate relation to them, as means, necessary and proper for carrying them into execution, questions on the constitutionality of laws passed for this purpose, will be of a nature sufficiently precise and determinate, for judicial cognizance and control. If on the one hand congress are not limited in the choice of the means, by any such appropriate relation of them to the specified powers, but may use all such as they may deem capable of answering the end, without regard to the necessity, or propriety of them, all questions relating to means of this sort must be questions of mere policy, and expediency, and from which the judicial interposition and control are completely excluded. . . . If, for example, congress were to pass a law prohibiting any person from bearing arms, as a means of preventing insurrections, the judicial courts, under the construction of the words necessary and proper, here contended for, would be able to pronounce decidedly upon the constitutionality of these means. But if congress may use any means, which they choose to adopt, the provision in the constitution which secures to the people the right of bearing arms, is a mere nullity; and any man imprisoned for bearing arms under such an act, might be without relief; because in that case, no court could have any power to pronounce on the necessity or propriety of the means adopted by congress to carry any specified power into complete effect.
This finishes our view of the legislative powers granted to the federal government; great and extensive as they must appear, they are in general such as experience had evinced to be necessary, or as the principles of a federal government had recommended to experiment, at least. In many instances these powers have been guarded by wise provisions, and restraints; some of which have been already noticed; the remainder will soon pass under review. Experience has already evinced the benefit of these restraints; and had they been more numerous, and more effectual, there is little reason to doubt that it would have contributed largely to the peace and harmony of the union, both heretofore, and hereafter. All governments have a natural tendency towards an increase, and assumption of power; and the administration of the federal government, has too frequently demonstrated, that the people of America are not exempt from this vice in their constitution. We have seen that parchment chains are not sufficient to correct this unhappy propensity; they are, nevertheless, capable of producing the most salutary effects; for, when broken, they warn the people to change those perfidious agents, who dare to violate them.
The Founders' Constitution
Volume 3, Article 1, Section 8, Clause 18, Document 12
The University of Chicago Press
Tucker, St. George. Blackstone's Commentaries: With Notes of Reference to the Constitution and Laws of the Federal Government of the United States and of the Commonwealth of Virginia. 5 vols. Philadelphia, 1803. Reprint. South Hackensack, N.J.: Rothman Reprints, 1969.
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