Court documents made public on Wednesday revealed that the prosecutors investigating the CIA interrogations of Abu Zubaydah were aware at the time, as early as 2006, that the Central Intelligence Agency had destroyed videotapes of the interrogations of al Qaeda operatives, long before the government publicly admitted to that in the court.

 The documents could change some aspects of conspirator Zacarias Moussaoui’s case, who was convicted for the September 11 attacks. In his appeal, Moussaoui says the documents were withheld and could have been used as evidence in his defense. At the same time, his lawyer is asking a federal court whether disclosing the tapes would have influenced his client’s decision to plead guilty.

Among the documents was a letter dated December 18, 2007 to a federal judge in Richmond, Va., from the Justice Department, acknowledging that the lead prosecutor in Moussaoui’s case was aware of the destruction of the interrogation tapes as early as February or March 2006, just as Moussaoui’s death penalty came under discussion.  

The prosecutor, Robert A. Spencer, denies the allegations and says he does not recall being told such information. However, as if the letter was not enough evidence, another prosecutor, who was not involved in the case, remembers telling Spencer about the destroyed videotapes at least on one occasion.

The government first admitted to the videotapes in November in a letter that acknowledged the fact that the CIA influenced the Moussaoui case through providing inaccurate information. At the same time, Moussaoui’s lawyers filed an appeal in November 2007, arguing that the government failed to provide reassurances that no other similar recordings could be found in the government’s possession.

As House Judiciary Committee Chairman John Conyers highlighted in a statement, the disclosure of the latest information will raise doubts and lower confidence in the American system of justice, and furthermore, the attorney general will have to be prepared to answer a lot of questions on the matter.