The Central Intelligence Agency’s attempt to keep secret the details of a defunct detention and interrogation program has escalated a battle between the agency and members of Congress and led to an investigation by the C.I.A.’s internal watchdog into the conduct of agency employees. (snip) The committee has spent several years working on a voluminous report about the detention and interrogation program, and according to one official interviewed in recent days, C.I.A. officers went as far as gaining access to computer networks used by the committee to carry out its investigation.