The recent anthrax investigation has brought to light the aggressive tactics of the FBI. It brought on questions about how far investigations should go and whether hardball tactics should remain legal.
Clint Van Zandt, former FBI agent and behavioral scientist for the FBI Academy. Van Zandt also wrote Facing Down Evil: Life on the Edge as an FBI Hostage Negotiator.
Lee Lofland, author of Police Procedure and Investigation, A Guide For Writers