P.D. Rank is a term used to describe the ranks of police officers in law enforcement. The four ranks are Captain (CAPT), Inspector (INSP), Detective (DET) and Sergeant (SGT). Captains are the highest rank, followed by Inspectors, Detectives and Sergeants. Captains are responsible for managing the operations of a police station, Inspectors are responsible for overseeing the activities of a police station, Detectives investigate crimes, and Sergeants are responsible for supervising police officers.