As has already been indicated (see above, § 18), the federal government, although a government of limited and delegated rather than general powers, has such implied powers as may be necessary to the reasonable exercise of the powers granted. This would be true without any express provision, but it is expressly declared that Congress shall have power "To make all laws which shall be necessary and proper for carrying into execution " the powers previously enumerated, and " all other powers vested by this constitution in the government of the United States or in any department or officer thereof" (Const. Art. I, § 8, ¶ 18). This clause of the constitution has two aspects: it recognizes the existence of implied powers, and it authorizes Congress to regulate the exercise of such powers by the departments or officers of the United States.

It would be impossible to enumerate in an exhaustive way the classes of statutory provisions which have been enacted by Congress in the exercise of its implied powers, and it would be equally impossible to forecast the legislation which might be proper under implied powers not, as yet, recognized or acted upon. A few examples of the exercise of implied powers will be sufficient for present purposes.

Under the general power to raise revenue and carry on the fiscal operations of the government, Congress passed two acts incorporating a United States bank (see McCulloch v. Maryland), and more recently has established a system of national banks. Under the power to regulate foreign and interstate commerce, Congress has passed a variety of statutes relating to navigation, immigration, and similar subjects. (See Gibbons, v. Ogden.) Under the power to borrow money and the general power implied from various provisions of the constitution to regulate the currency, Congress has made treasury notes a legal tender in the payment of debts (Legal Tender Case). Under the power given to each House of Congress to determine the rules of its proceedings and to act as a co-ordinate branch of the legislative department, punishment of contempts of the authority of either House may be provided for, and such punishment may be inflicted on persons who are not members (Anderson v. Dunn and Kilbourn v. Thompson). Congress may regulate the methods of appointment of officers and employes of the United States, and prescribe their qualifications so far as such qualifications are not prescribed in the constitution itself, and it may prohibit and punish misconduct on the part of such officers (Ex parte Curtis). Under the power to regulate commerce and in the exercise of the powers incident to the sovereignty which belongs to the government of the United States, Congress has provided for the exclusion of the Chinese (Chinese Exclusion Case and Fong Yue Ting v. United States),