Points of diversion typically are physicians, pharmacists and pharmacies, forged or stolen prescription forms, and illegal prescription cashing. When the Diversion Investigation Unit receives a complaint, regardless of the source, an officer is assigned to investigate the case. The investigator formulates an investigative plan based on the information reported by the complainant. Preliminary investigation involves obtaining available information on the target subject, followed by observation of the work place of the subject, noting such factors as patient traffic, type of practice, and general age of the patients. The investigator may scan the prescription records of local pharmacies to determine the physician's prescription-writing habits. At this point in the investigation, there is probably enough information to determine whether criminal activity is indicated. If criminal activity is suspected, an undercover will be sent to the physician to attempt a prescription purchase, equipped with a tape recorder. The undercover officer is in constant voice communication with the supervisor and the investigating officer. Evidence obtained in the undercover work is carefully documented and maintained. Return visits by the undercover officer establish that the physician is acting in a particular pattern so as to ensure a good case. Only after evidence has been presented to a grand jury and an indictment obtained is an arrest warrant issued.