From The National Security Archive:
The State Department today released a February 2006 internal memo from the Department's then-counselor opposing Justice Department authorization for "enhanced interrogation techniques" by the CIA. All copies of the memo (Document 1), which reflect strong internal disagreement within the George W. Bush administration over the constitutionality of such techniques, were thought to have been destroyed. But the State Department located a copy and declassified it in response to a Freedom of Information Act request by the National Security Archive.
The author of the memo, Philip D. Zelikow, counselor to then-Secretary of State Condoleezza Rice, described the context of the memo in congressional testimony on May 13, 2009, and in an article he had previously published on foreignpolicy.com site on April 21, 2009.