26 years a detective in the sussex police department. internationally recognized for his work in investigative interview techniques. when griffiths was a rookie, british interrogation rules were much like they are in the u.s., but they are not anymore. >> what happened to precipitate these changes in the united kingdom? >> changes really came about through problems. >> like a national scandal after a series of high-profile false confessions, including an arson/murder case eerily similar to robert davis'. >> the government of the day instigated a whole review of the way that prisoners were dealt with in custody. >> the result? a complete overhaul of the system. every officer in the uk retrained to rigorous standards that apply in every region of the country. strict rules were put in place for suspect interviews. all interviews in serious cases video-recorded. >> there are two cameras up there.