Military Commissions Act

United States [2006]

Also known as: MCA

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July 17, 2026

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The Military Commissions Act of 2006 (MCA) was a U.S. law that established a system of military commissions to try individuals deemed "enemy combatants." This act was passed in response to the Supreme Court's ruling in Hamdan v. Rumsfeld, which found the administration's initial system of commissions to be in violation of international law and the Uniform Code of Military Justice.1

The MCA aimed to provide a statutory basis for these commissions and, significantly, prevented non-U.S. citizens designated as enemy combatants from challenging their detentions in federal courts. This provision was later challenged and, in Boumediene v. Bush (2008), the Supreme Court ruled that it unconstitutionally suspended the writ of habeas corpus. The treatment of detainees, particularly at Guantánamo Bay, and the use of enhanced interrogation techniques, were highly controversial aspects surrounding the MCA's passage.12

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George W. Bush
Treatment of detainees
…that year, Congress passed the Military Commissions Act, which gave the commissions the express statutory basis that the court had found lacking; the law also prevented enemy combatants who were not American citizens from challenging their detention in the federal courts.
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…that year, Congress passed the Military Commissions Act, which gave the commissions the express statutory basis that the court had found lacking; the law also prevented enemy combatants who were not American citizens from challenging their detention in the federal courts.
Read More

Guantánamo Bay detention camp
…restored in 2006 by the Military Commission Act, which also denied the federal courts jurisdiction to hear habeas corpus petitions on behalf of foreign detainees. In 2008, however, the court overturned the latter provision of the law by ruling (in Boumediene v. Bush) that foreign detainees did have the right…
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…restored in 2006 by the Military Commission Act, which also denied the federal courts jurisdiction to hear habeas corpus petitions on behalf of foreign detainees. In 2008, however, the court overturned the latter provision of the law by ruling (in Boumediene v. Bush) that foreign detainees did have the right…
Read More