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Public SafetyTargetingPositive

Kansas City Gun Experiment — Directed Hot-Spots Patrol

University of Maryland / Kansas City Police Department · Kansas City, MO, USA · 1992

Summary

The Kansas City Gun Experiment established that targeted police patrol can dramatically reduce gun crime — but only when the targeting is precise. Officers were instructed to focus specifically on gun detection in an 80-block area, not simply to increase general presence. The result was a 49% drop in gun crimes and 65% increase in gun seizures in the target area, with no evidence that crime simply moved to adjacent areas. The study launched a generation of hot-spots policing research that has now replicated the core finding in dozens of cities across multiple countries. What makes hot-spots work is concentration: crime is not evenly distributed, and the small percentage of addresses that generate the majority of crime can be targeted with surgical precision. The question subsequent research has grappled with is less 'does hot-spots policing reduce crime?' and more 'which tactics work within hot spots, and what are the costs to community relations?'

Research question

"Does intensive police patrol specifically targeting high-crime hot spots — with active gun seizure through traffic stops and field interviews — reduce gun crime in those areas?"

Methodology

Intervention

Officers in an 80-block high-crime beat (Beat 144) were directed to focus patrol on gun detection through traffic stops, pedestrian checks, and field interviews during high-crime evening hours (9pm–1am). A comparison beat was randomly selected to serve as a control. The target beat received approximately 3× as many patrol hours, resulting in a 65% increase in gun seizures over 29 weeks.

Assignment

Quasi-experimental with matched control beat; Sherman & Rogan (1995) used time-series comparison of gun crime in target vs. matched control beat; not a true randomized trial but considered the cleanest available evidence

Sample size

Two patrol beats (~80 blocks each); 29-week intervention

Primary outcome

Gun crimes (drive-by shootings, assaults with firearms); gun seizures; overall violent crime in target beat vs. comparison

Effect estimate

Gun crimes fell 49% in target beat during intervention; drive-by shootings fell from 9 to 1 during intervention period; gun seizures increased 65%; no significant increase in gun crime in surrounding beats (no displacement detected); comparison beat showed no significant change

Decision

Study launched an era of hot-spots policing research; over 20 subsequent randomized and quasi-experimental studies across multiple cities replicated the core finding; hot-spots patrol is now considered one of the most evidence-based police strategies; National Academy of Sciences reviewed the hot-spots literature in 2004 and 2018 and confirmed effectiveness; COPS Office adopted hot-spots frameworks in federal policing grants

Result

Positive

Gun crimes fell 49% in target beat during intervention; drive-by shootings fell from 9 to 1 during intervention period; gun seizures increased 65%; no significant increase in gun crime in surrounding beats (no displacement detected); comparison beat showed no significant change

Evidence strength

Moderate

Quasi-experimental design with replication support.

Replication status

Replicated

Institution

University of Maryland / Kansas City Police Department

Location

Kansas City, MO, USA

Year

1992

Policy area

Public Safety

Mechanism

Targeting

Other trials of this mechanism

Cite this entry

University of Maryland / Kansas City Police Department. (1992). Kansas City Gun Experiment — Directed Hot-Spots Patrol. The Experiment Society Registry. Retrieved from https://www.experimentsociety.org/registry/kansas-city-gun-experiment (primary report: https://www.tandfonline.com/doi/abs/10.1080/07418829500096221)

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Mentioned in the Dispatch

Issue 03 · April 13, 2026

What hot spots policing actually showed.

The most replicated finding in criminology is also the most misapplied.

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