Necessary and Proper Clause definition (or elastic clause) is one of the most significant and powerful clauses in the US Constitution. This clause enables Congress to issue the laws that are needed for the performance of its duties established by the Constitution. In other words, the necessary and proper clause is a means by which the Congress exercises its powers.


The Necessary and Proper Clause was drafted as Clause 18 of Article 1 of the US Constitution in addition to the Clauses 1-17, which list all of the powers that Congress has over the legislation of the US. Clause 18 states that the Government can “make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution.” The Necessary and proper clause definition is important because it helps Congress to decide whether, how, and when the new law should be issued, taking into account the principle of separation of powers. In other words, it does not give Congress any power to regulate or prohibit another branch in exercising its constitutional functions and roles.

The Clause was criticized by those who opposed the ratification of the Constitution. It caused arguments between Federalists and Anti-Federalists. The first group asserted that the clause would enable them to improve the execution of its power, which they already have. The latter, however, argued that the government would have enormous power and dominance. Nevertheless, the Necessary and Proper Clause and its term were eventually generated in the second half of the 20th century. Congress refers to this clause every time when there is a controversial issue, especially during legal proceedings at the federal courts.