The Military Commissions Act of 2006, also known as HR-6166, was an Act of Congress signed by President George W. Bush on October 17, 2006. The Act's stated purpose was "to authorize trial by military commission for violations of the law of war, and for other purposes".

Hamdan v. Rumsfeld, 548 U.S. 557 (2006), is a United States Supreme Court case in which the Court held that military commissions set up by the Bush administration to try detainees at Guantanamo Bay violated both the Uniform Code of Military Justice (UCMJ) and the Geneva Conventions ratified by the U.S.