Chief Inspector (Ch Insp) is a rank in British Police forces. It is senior to Inspector and junior to Superintendent.
The rank was first introduced into the Metropolitan Police in 1868 and was first used by Adolphus Williamson, the first head of the Detective Branch (later the Criminal Investigation Department). When Williamson was promoted to Superintendent shortly afterwards, three of his Inspectors were promoted to Chief Inspector and the rank was firmly established. In 1869 it was also introduced as a uniformed rank, with the senior assistant to the Divisional Superintendent being given the rank. The rank subsequently spread to other police forces.
From 1933, every Metropolitan Police division had two Chief Inspectors: Chief Inspector (Administration) and Chief Inspector (Crime) (the latter also being an administrative officer and not replacing the Divisional Detective Inspector). In 1949, Sub-Divisional Inspectors were also regraded as Chief Inspectors.
Today, the function of Chief Inspectors varies from force to force. They may assist Basic Command Unit (BCU) commanders, command smaller units, or fill various staff posts.
Detective Chief Inspector (DCI) is usually the minimum rank held by a Senior Investigating Officer (SIO), who heads major investigations (into murder, for example), and a pool of these officers usually works out of force headquarters or major police stations. The senior Criminal Investigation Department (CID) officer in each BCU usually also holds this rank.
The rank badge of a Chief Inspector is three stars ("pips") worn on the epaulettes. This is the same badge as a Captain in the British Army.
Chief Inspector was one of the ranks proposed for abolition in the police organisational reforms of the 1990s, but all forces still retain it.