The necessary-and-proper clause (also know as the Congress' power to make all laws clause and the elastic clause) refers to a provision (section eight, paragraph 18) in Article One of the United States Constitution granting Congress the power "to make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this Constitution in the Government of the department or officer thereof."

Before 1926, there was no agreed upon label for Clause 18 of Article I, Section 8--Congress' vested power to make all laws. However, Justice Brandeis' 1926 reference to Congress' power to make all laws clause as the Necessary and Proper clause in Lambert v. Yellowley, 272 U.S. 581, 596 (1926) became the label of choice and was universally adopted by the courts as well as received Congress' imprimatur. (see the heading of 50 U.S.C. § 1541(b) (1994) (purpose and policy of war powers resolution)).

Labeling Article I, Section 8, Clause 18 as the Necessary and Proper Clause promotes judicial activism. Generally, articles, sections, and clauses of the United States Constitution take on unofficial identification labels that serve to call to mind the main thesis of that article, section or clause. The judiciary's reference to Article I, Section 8, Clause 18 as the Necessary and Proper clause de-emphasizes the main thesis of Clause 18: that it is the United States Congress who has the power to make all laws. Over time, this power de-emphasizing mark has promoted judicial activism at the deprivation of Congress' power to make all laws by focusing on the Court's control over the limits of Congress' power to make all laws rather than focusing on the power itself. By referring to Article I, Section 8, Clause 18 as the Power to Make All Laws clause calls to mind the main thesis of Clause 18 and makes it clearer that it is Congress who has the power to make all laws.

The interpretation of the Clause 18 of Article I, Section 8 phrase has been controversial, especially during the early years of the republic. Strict constructionists interpret the clause to mean that Congress may make a law only if the inability to do so would cripple its ability to apply one of its enumerated powers ("foregoing powers"). Others argue that the elastic clause expands the authority of Congress to all areas tangentially related to one of its enumerated powers. It is often known as the elastic clause because of the great amount of leeway in interpretation it allows; depending on the interpretation, it can be used to "stretch" or expand the powers of Congress, or allowed to "contract," limiting Congress.

One early controversy involving the clause were the charterings of the Bank of the United States. Although the Constitution does not explicitly give Congress the authority to establish a national bank, the move was justified as being a "necessary and proper" exercise of Congress authority to make laws regulating interstate commerce under the commerce clause. Alexander Hamilton made the bank by loosely interpreting the constitution because he, a Federalist, was the party in power; but Thomas Jefferson, a Democratic-Republican, wanted to strictly interpret the constitution, in order to limit the Federalists' power. In McCulloch v. Maryland, Chief Justice John Marshall ruled that a state cannot sue a federal institution (the national bank) under the Supremacy Clause of the Constitution. However, the elastic clause was necessary to establish that Congress has and had the power to establish national banks in the first place.

It is important to note that the clause, unlike the enumerated clauses, does not in itself grant Congress any new powers. Instead, it widens the powers that Congress has under the other clauses. For example, in the McCulloch case mentioned above, the elastic clause was not intepreted to grant Congress the authority to establish a national bank. It merely allows the Congressional power to coin money and the power to control interstate commerce to be interpreted to allow Congress the power to charter a national bank.

The elastic clause has been paired with the Commerce Clause in particular to provide the constitutional basis for a wide variety of laws. For example, legislation making it a federal crime to transport a kidnapped person across state lines is justified by considering the act to be commerce. A series of Supreme Court decisions resulting in the desegregation of private businesses, such as hotels and restaurants, was supported on the basis that these business establishments, although not directly engaged in interstate commerce, no doubt had an effect on it. Since the New Deal the Supreme Court has been reluctant to limit the scope of authority allowed under the combination of these clauses. United States v. Lopez was the first modern case finding limits to Congress's authority in this regard.

See also

• Implied powers
• Judicial activism

United States Constitution