## Overview and Mission The Chicago Police Department (CPD) is one of the oldest municipal police forces in the United States, established in 1835 with the election of Orsemus Morrison as the city’s first constable[1][2][7]. Its core mission is to protect life and property, enforce laws, and maintain order in Chicago—a city with a population of nearly 3 million and a complex urban landscape. The department operates under the jurisdiction of the City of Chicago and is overseen by a superintendent appointed by the mayor. ## Historical Development CPD’s early years were marked by rapid expansion and organizational change. In 1855, the department underwent a major reorganization under Chief Cyrus P. Bradley, who introduced 24-hour patrols, increased the force size, and divided the city into three police precincts—each with its own station house[1][2][3]. Uniforms were adopted in 1858, and the first detective division was established in 1860[3]. The department’s structure and practices were heavily influenced by local politics, with officers often appointed based on political connections until civil service reforms in 1895 introduced merit-based hiring[2][4]. The late 19th and early 20th centuries saw technological innovations such as the first patrol wagon (1881), motorized vehicles (1908), and early experiments with radio communications in the 1920s[3]. CPD was also among the first to employ women (as matrons in 1885 and policewomen in 1913) and African American officers (1872), though both groups faced significant restrictions initially[4][5]. ## Key Achievements and Innovations CPD has a long history of adapting to the challenges of a growing, diverse city. It played a pivotal role in responding to labor unrest, organized crime, and civil rights movements throughout the 20th century[8]. The department has also been a testing ground for