The Rapid City Police Department was established in 1882 as a result of an Act enacted by the Legislative Assembly of the Dakota Territory. Beginning with just one City Marshal, the Police Department has evolved to a current authorized strength of 141 employees, comprised of 108 sworn officer and 33 civilians.

Under the Rapid City Police Department Rules and Procedures, "The Rapid City Police Department shall enforce the ordinances of the City of Rapid City and the laws of the State of South Dakota, and carry out all duties and responsibilities attributed to the Police Department through the Mayor of the City of Rapid City pursuant to the Code of Ordinances of the City of Rapid City, South Dakota, Chapter 23, which derives authority from the Constitution of the State of South Dakota and SDCL 9-29-1 9-29-2 and 9-29-19".

The Rapid City Police Department is responsible for the preservation of the public peace, prevention of crime, apprehension of criminals, protection of rights of persons and property, operation and enforcement of the laws and the rules and regulations made in the furtherance thereof

The primary responsibilities of the Police Department include:

• Response to calls for services by the citizens of the City.
• Resolution of problems, concerns and issues of the citizens of the City as they relate to matters of law enforcement.
• Prevention of crime and delinquency through comprehensive 24-hour police patrol.
• Response for assistance upon request of County and State agencies.
• Maintenance of public order and safety through the arrest of violators of the law.
• Maintenance of orderly traffic flow and the resolution of traffic violations.
• Education of the public in prevention and the requirements of and conformance with the law.
• Maintenance of records and reports of all activities of the agency. Cooperation with other agencies in the analysis of data to plan and coordinate future crime prevention and public safety activities.

The Department provides protection and services for over 50 square miles* of densely populated, urban, and suburban areas. Growth in the City has shown a steady increase, exceeding 62,000 people in 2005. The Department's call load reflects the City's growth, responding to 102,194 calls annually*.

* Reflects 2006 data