The Coevolution of Public and Private Security in Nineteenth‐Century Chicago

The coevolution of private detective agencies and municipal police bureaucracies in mid‐nineteenth‐century Chicago arose from the breakdown of an older system in which the provision of law enforcement was delegated to local communities. The growth of anonymity and the presence of strangers in a city undergoing massive changes in transportation undermined this delegative system and created the perception of new public security threats. These threats were compounded by the mobilization of ethnicity in partisan politics. To address these new concerns, political and e conomic elites did not innovate, but turned to traditional practices like special deputization. The use of deputization allowed some law officers to sell their services as entrepreneurs to private firms, while also paving the way for a new bureaucratic police department. Networks of security providers locked in this transformation and made public and private policing alike a permanent feature of the city's institutional landscape.