Did he have a need to know? Even if you have the requisite clearance, you cannot access classified material if you don’t have a legitimate need to know. I don’t think covering up a screw-up counts.

Since he was being asked to testify in detail on the 9/11 stuff, that would probably constitute need to know. As far as the clearance goes, there is such a thing as being cleared by executive order; I doubt very much that there would be any question of maintaining a clearance for a former Special Assistant for the NSC.

Betcha he doesn’t have that clearance now, though.