The Elastic Clause, also known as the Necessary and Proper Clause, is a clause in Article I, Section 8 of the United States Constitution. It grants Congress the power to pass all laws necessary and proper for carrying out the enumerated powers and all other powers vested by the Constitution in the Government of the United States or in any Department or Officer thereof. The Elastic Clause is the constitutional source of the vast majority of federal laws, including laws establishing the machinery of government and substantive laws ranging from antidiscrimination laws to labor laws.

The Elastic Clause has been paired with the Commerce Clause to provide the constitutional basis for a wide variety of federal laws. For example, various reforms involved in the New Deal were found to be necessary and proper enactments of the objective of regulating interstate commerce. In addition to both clauses being used to uphold federal laws that affect economic activity, they also were used to justify federal criminal laws as well.

The Elastic Clause has been interpreted in various ways. One way is to pick apart its individual words and give each key term an independent meaning. Another way is to look at the clause as a single, undifferentiated provision and try to discern the range of laws that the Clause, viewed holistically and purposively, tries to authorize. One vision sees the Clause as a codification of principles of agency law that allow agents to exercise certain defined powers that are “incidental” to the main objects of the documents that empower the agents. Another vision views the Clause as carrying forward ideas from a resolution adopted by the Constitutional Convention that authorized the Convention to propose amendments to the Articles of Confederation that would make the federal government more effective.

In summary, the Elastic Clause is a clause in the United States Constitution that grants Congress the power to pass all laws necessary and proper for carrying out the enumerated powers and all other powers vested by the Constitution in the Government of the United States or in any Department or Officer thereof. It is also known as the Necessary and Proper Clause and is the constitutional source of the vast majority of federal laws.