The Justice Department and the CIA's internal watchdog unit yesterday began a joint preliminary inquiry into the spy agency's destruction of hundreds of hours of videotapes showing interrogations of top operatives of al-Qaeda. Lawyers with the Center for Constitutional Rights said they feared that the CIA and other U.S. agencies also destroyed evidence in their client Majid Khan's case, and they argued in a 24-page filing with the U.S. Court of Appeals for the District of Columbia Circuit that Khan was subjected to systematic torture.