The Virtual Museum of the City of San Francisco gives a detailed history of the blue police call boxes.
The blue boxes were installed beginning in the late 19th Century and were a primary means of communication between the beat and the station house until 1967 when two-way portable radios were introduced.
Following the 1906 earthquake and fire, two new telephone switchboards were purchased. One was installed at the Hall of Justice on Portsmouth Plaza in 1913, and the other was held in storage in case of another disaster. When the Hall of Justice moved to Bryant Street in the late 1950s, the spare was taken from storage and placed on-line at the new Bryant Street location.
During Dianne Feinsteinís years in the Mayorís office (1978-1988), this system was renamed Mayorís Emergency Telephone System--METS. It was this old switchboard, first purchased in 1913, that ran emergency telephone communications in San Francisco from the late 1950s until 1990, including the three days after the 1989 earthquake when most telephone service was out.
In 1990, voters authorized the purchase of a digital electronic telephone switch, which was then placed in the basement of the Central Fire Alarm Station on Turk Street to be used for all emergency communications.
Today, METS telephones are located in the homes and offices of City department heads, as well as all police and fire stations. The system is also connected to the State of California's satellite telephone system for direct communication with the Governor's Office of Emergency Services in Sacramento, as well as the emergency operations centers of surrounding counties.
The old police call boxes on street corners now contain METS telephones that link into the Central Fire Alarm Station and the State's satellite communications system.