The Impact of the First Professional Police Forces on Crime

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IZA Seminar

Place: Schaumburg-Lippe-Str. 9, 53113 Bonn

Date: 23.10.2018, 12:15 - 13:30


Presentation by 

Randi Hjalmarsson (University of Gothenburg)


This paper evaluates the impact of the introduction of professional police forces on crime using manually transcribed archival records and two natural experiments in history: the formation of the London Metropolitan Police in 1829 (the first professional force worldwide) and the subsequent roll-out of professional forces to the counties of England and Wales from 1839 to 1856. These new professional police were explicitly tasked with deterring crime, which contrasts the mandate of the old, informal ‘police’ to simply apprehend criminals. Estimating pre-post, difference-in-differences as well as event-study specifications, we find evidence that the creation of a professional police force reduces crime overall and across crime categories. Our estimates of the effect of the London Metropolitan police on violent crime range from -26% to -57%, where the former corresponds to charges and the latter to daily incidents. London property crime incidents decreased by 26% while charges increased by 21%. This is consistent with a crime reducing deterrence and/or incapacitation effect on property crime being offset by increased crime reporting and/or clearance rates. A difference-in-differences analysis of county force roll-out finds that high quality police forces, measured by the population to force ratio, reduced overall crime by 18% (and across crime categories), while there was no net crime reducing effect of a force that was not sufficiently large.

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