Police Dept. Rank is a term used to describe the various ranks within a police department. The four ranks are Inspector (INSP), Detective (DET), Sergeant (SGT) and Commander (CMDR). Inspectors are responsible for overseeing investigations and providing guidance to detectives. Detectives are responsible for conducting investigations and gathering evidence. Sergeants are responsible for supervising officers and managing operations. Commanders are responsible for managing the overall operations of the police department.