On June 8, 2002, Assistant Attorney General Jay Bybee sent a memo to Attorney General John Ashcroft titled, “Determination of Enemy Belligerency and Military Detention.” In it, Bybee determined that U.S. citizen Jose Padilla, as an associate of al Qaeda, could be captured as a prisoner by the U.S. Armed Forces in an international armed conflict. Additionally, he determined that the Posse Comitatus Act (which prohibited the Army and Air Force from maintaining law and order within the U.S.) did not apply to Padilla.
– Jay S. Bybee, “Determination Of Enemy Belligerency And Military Detention” (memo to Attorney General), U.S. Department of Justice, June 8, 2002