Enemy combatant Enemy combatant is a term historically referring to members of the armed forces of the state with which another state is at war . Prior to 2008 , the definition was : " Any person in an armed conflict who could be properly detained under the laws and customs of war . " In the case of a civil war or an insurrection the term " enemy state " may be replaced by the more general term " Party to the conflict " ( as described in the 1949 Geneva Conventions ) . In the United States the phrase " enemy combatant " was used after the September 11 attacks by the George W . Bush administration to include an alleged member of al Qaeda or the Taliban being held in detention by the U . S . government as part of the war on terror . In this sense , " enemy combatant " actually refers to persons the United States regards as unlawful combatant s , a category of persons who do not qualify for prisoner - of - war status under the Geneva Conventions . Thus , the term " enemy combatant " has to be read in context to determine whether it means any combatant belonging to an enemy state , whether lawful or unlawful , or if it means an alleged member of al Qaeda or of the Taliban being detained as an unlawful combatant by the United States . In the United States on March 13 , 2009 , the Obama administration announced its abandonment of the Bush administration ' s use of the term " enemy combatant " . Change of meaning in the United States . In the 1942 Supreme Court of the United States ruling Ex Parte Quirin , the Court uses the terms with their historical meanings to distinguish between unlawful combatant s and lawful combatant s : In the wake of the September 11 , 2001 attacks the United States Congress passed a resolution known as the Authorization for Use of Military Force Against Terrorists ( AUMF ) on September 14 , 2001 , wherein the Congress invoked the War Powers Resolution . Using this authorization granted to him by Congress , on November 13 , 2001 , President George W . Bush issued a Presidential Military Order : " " Detention , Treatment , and Trial of Certain Non - Citizens in the War Against Terrorism " " . The administration chose to call those who it detained under the Presidential Military Orders " enemy combatants " . Since then , the administration has formalized its usage of the term by using it specifically for detained alleged members and supporters of al - Qaida or the Taliban . For example This lead has been followed by other parts of the Government and some section of the American news media . The result of this new usage means that the term " enemy combatant " has to be read in the context of the article in which it appears as to whether it means a member of the armed forces of an enemy state , or if it means an alleged member of " al Qaida " held prisoner by the United States . Military Commissions Act . Following the Supreme Court ' s ruling of lexi Hamdan v . Rumsfeld the United States Congress passed the Military Commissions Act of 2006 which contains a definitions for lawful and unlawful enemy combatants . The Military Commissions Act mandated that Guantanamo captives were no longer entitled to access the US civil justice system , so all outstanding habeas corpus petitions were stayed . Boumediene v . Bush . On June 12 , 2008 , the United States Supreme Court ruled , in Boumediene v . Bush , that the Military Commissions Act could not remove the right for Guantanamo captives to access the US Federal Court system . And all previous Guantanamo captives ' habeas petitions were eligible to be re - instated . The judges considering the captives ' habeas petitions would be considering whether the evidence used to compile the allegations that the detainees were enemy combatants justified a classification of " enemy combatant " . Following the Supreme Court ' s Boumediene v . Bush ruling . On February 20 , 2009 , the administration of President Barack Obama sided with the Bush Administration ' s interpretation of law when they argued to bar access to civil courts sought by enemy combatants held at the Bagram Airfield in Afghanistan . During a hearing on 23 October 2008 US District Court Judge Richard J . Leon commented on the ambiguity of the term " enemy combatant " . Farah Stockman , writing in the " Boston Globe " , quoted Leon ' s remarks characterizing him as having " " lashed out " " at Congress and the Supreme Court for leaving the term undefined : On 27 October 2008 Leon ruled that the definition of " enemy combatant " he would use was that set forth in the 2004 rules for Combatant Status Review Tribunal s . Defense attorneys for Lakhdar Boumediene and his fellow Bosnians of Algerian descent were pleased with the definition because the DoD had long since dropped the allegation that they had plotted to attack the US Embassy in Sarajevo , and they felt that none of the remaining allegations met the Leon ' s definition . Obama Presidency abandons the term " enemy combatant " . On March 13 , 2009 United States Attorney General Eric Holder issued a statement that the United States had abandoned the Bush administration term " enemy combatant " . The statement said , " " " As we work toward developing a new policy to govern detainees , it is essential that we operate in a manner that strengthens our national security , is consistent with our values , and is governed by law . " " However , various human rights groups noted it as primarily a symbolic act . The United States continues to hold detainees at the Guantanamo Bay detention camp .