Washington (CNN) The CIA explored using a drug it believed could act like a truth serum to interrogate prisoners about possible terror attacks in the immediate aftermath of 9/11, according to a once-classified report made public Tuesday.

A newly released 90-page account details the existence of a drug research program called "Project Medication" and discloses how the CIA's Office of Medical Services maintained an influential role in the development of detention and interrogation practices.

Specifically, the documents reveal the CIA researched the possibility of using a psychoactive drug called Versed to interrogate high-level prisoners.

"The history reveals that CIA doctors were hunting for a 'truth serum' to use on prisoners as part of a previously secret effort called Project Medication," American Civil Liberties Union staff attorney Dror Ladin said in a statement, also noting records show that CIA doctors were "indispensable" to the effort of "legitimizing the program."

The CIA determined that the drug was "considered possibly worth a trial if unequivocal legal sanction first were obtained" but ultimately opted not to ask government lawyers to approve the use of the drug.

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