What You'll Learn
The Concept
For much of the twentieth century, random motorized patrol occupied a central position in American policing. The underlying assumption seemed logical: if potential offenders saw police cars regularly circulating through neighborhoods, they would fear apprehension and refrain from committing crimes.
The Kansas City Preventive Patrol Experiment, conducted during the early 1970s, subjected this assumption to an unusually rigorous field test. Police beats received different levels of routine preventive patrol. Some received increased patrol, some continued ordinary levels, and others received substantially reduced routine patrol while police still responded to calls for service.
The experiment found that changing the level of routine random preventive patrol did not produce the expected measurable differences in crime, citizen fear, or satisfaction with police. The findings did not establish that police presence is irrelevant or that patrol cannot reduce crime. Instead, they challenged the assumption that simply placing additional officers in automobiles and having them patrol randomly will necessarily produce substantial crime-control benefits.
That distinction later became extremely important. Research increasingly began examining where, when, and how police resources were deployed rather than merely asking how many officers were patrolling.
The Newark Foot Patrol Experiment added another important dimension. Research surrounding foot patrol suggested that even when measured crime did not necessarily decline, residents in areas receiving foot patrol could experience reduced fear and improved perceptions of neighborhood conditions.
These studies therefore helped change the way police effectiveness was conceptualized. An agency's success might involve more than reductions in reported crime. Researchers increasingly considered outcomes such as fear of crime, disorder, citizen satisfaction, community confidence, police legitimacy, victimization, and quality of life.
Perhaps the most lasting contribution of these studies was methodological. Police practices that appeared logical could — and should — be tested. That principle became one of the intellectual foundations of modern evidence-based policing.
Real-World Application
A police chief considering whether to add patrol officers to a high-crime district should ask: where exactly will those officers be deployed, doing what, at what times? The Kansas City findings suggest that simply adding cars to random patrol is unlikely to produce measurable results. Directed patrol — officers assigned to specific locations during specific time windows based on crime analysis — has a substantially stronger evidence base.
Why It Matters
For Police Officers
Understanding what research says about patrol helps officers and supervisors make better deployment decisions. The question is not just 'how many officers' but 'where, when, and doing what.' Evidence-based patrol strategies are more likely to produce real crime reductions than tradition-based assumptions.
For Students
These experiments are foundational to understanding how policing research works. They demonstrate that even widely accepted practices should be tested empirically — and that the results can be surprising. They also introduced the concept that police effectiveness includes more than crime statistics.
Think About It
Why might police administrators have resisted the findings of the Kansas City experiment? What organizational or political pressures might have made it difficult to change patrol practices?
The Newark study found that foot patrol reduced fear of crime even when it did not reduce crime itself. Is reducing fear of crime a legitimate goal for policing? Why or why not?
How do these experiments support the broader argument for evidence-based policing? What would policing look like if every major strategy were subjected to similar testing?
Sources & Further Reading
Kelling, G.L., Pate, T., Dieckman, D., & Brown, C.E. (1974). The Kansas City Preventive Patrol Experiment. Police Foundation.
Police Foundation. (1981). The Newark Foot Patrol Experiment. Police Foundation.
National Institute of Justice. Evidence-Based Policing. nij.gov.