C.I.A. Was Urged to Keep Interrogation Videotapes - New York Times

It now appears that The C.I.A. was told to preserve the torture video tapes.

White House and Justice Department officials, along with senior members of Congress, advised the Central Intelligence Agency in 2003 against a plan to destroy hundreds of hours of videotapes showing the interrogations of two operatives of Al Qaeda, government officials said Friday.

So, they were wold not to by a number of lawyers, and decided to do so anyway, when things started getting hot, with legal and Congressional investigations ramping up.

Sounds like obstruction of justice to me, in fact, I'd call it a slam dunk.