Home > West's Encyclopedia of American Law > Commerce Clause

The provision of the U.S. Constitution that gives Congress exclusive power over trade activities among the states and with foreign countries and Indian tribes.

Article 1, Section 8, Clause 3, of the Constitution empowers Congress "to regulate Commerce with foreign Nations, and among several States, and with the Indian Tribes." The term commerce as used in the Constitution means business or commercial exchanges in any and all of its forms between citizens of different states, including purely social communications between citizens of different states by telegraph, telephone, or radio, and the mere passage of persons from one state to another for either business or pleasure.

Intrastate, or domestic, commerce is trade that occurs solely within the geographic borders of one state. As it does not move across state lines, intrastate commerce is subject to the exclusive control of the state.

Interstate commerce, or commerce...