How do I trace the record of a prisoner in a police cell or lock up?

The records of police stations sometimes include detention books, bail books or registers of persons held in police cells. If your enquiry concerns a police cell or lock-up, the first task is to find out which police force would have operated at the time and place in question, and where (if at all) the station records survive. For further details go to the Knowledge Base entry on Police Records Locations.