( CNN ) -- A formerly classified government memo authorizing the drone attack that killed American terror suspect Anwar al-Awlaki was released on Monday by a federal court . The government for years fought disclosure of the 2010 document produced by the Justice Department 's Office of Legal Counsel , saying it would harm national security . The legal memo shows how the Obama administration laid out its case in an internal debate over the attack that killed the suspected al Qaeda operative in a 2011 CIA drone strike . The Justice Department considered Yemeni-based Al Qaeda in the Arabian Peninsula ( AQAP ) an `` enemy force . '' The document said the government had no feasible way to arrest al-Awlaki and concluded the authorization of military force against al Qaeda applied to him as it would a non citizen . The 2nd U.S . Circuit Court of Appeals ordered the release of a redacted version of the memo in response to a Freedom of Information Act lawsuit filed by the American Civil Liberties Union and New York Times .
The suspect Khalid al - Awlaki was killed in a 2011 drone strike . The U.S. said he was top operative for al Qaeda in Yemen . Government sought to keep memo secret , saying release could harm national security . Memo said that force authorization against al Qaeda in general belonged to al - Awlaki .