The U.S. Constitution gives Congress the authority "to regulate Commerce…among the several States." In 2005, the U.S. Supreme Court held that the Interstate Commerce Clause should be construed so broadly as to allow the federal ban on marijuana to be enforced against medical marijuana patients whose use was perfectly legal under state law and whose cultivation and consumption of the plant had occurred entirely within the confines of a single state.
The final vote in that controversial case, Gonzales v. Raich, was 6–3. The most forceful of the dissents was written by Justice Clarence Thomas. "If Congress can regulate this under the Commerce Clause," he protested, "then it can regulate anything—and the Federal Government is no longer one of limited and enumerated powers."
