WHAT IS A POLICE BOX
A police box is a British telephone kiosk or callbox located in a public place for the use of members of the police, or for members of the public to contact the police. Unlike an ordinary callbox, its telephone is located behind a hinged door so it can be used from the outside, and the interior of the box is, in effect, a miniature police station for use by police officers to read and fill out reports, take meal breaks, and even temporarily hold prisoners until the arrival of transport.
Police boxes predate the era of mobile telecommunications; now British police officers carry two-way radios and/or mobile phones rather than relying on fixed kiosks. Most boxes are now disused or have been withdrawn from service.
The typical police box contained a telephone linked directly to the local police station, allowing patrolling officers to keep in contact with the station, reporting anything unusual or requesting help if necessary. A light on top of the box would flash to alert an officer that he/she was requested to contact the station. Members of the public could also use the phone to contact a police station in an emergency or, in the case of the Metropolitan Police, for assistance with any matter normally within the purview of the police.