August 5, 2002

Researchers link 'broken windows' policing
with drop in serious crime

Full report (pdf)

There is a significant link between targeting minor crime and a drop in serious crime, even when community factors such as unemployment and the number of young people are considered, according to a study from the California Institute for County Government at California State University, Sacramento.

The study, "Does 'Broken Windows' Law Enforcement Reduce Serious Crime?" examined all California counties from 1989 to 2000.

It found for the first time a generalizealble statistical tie between so-called "broken windows" policing and a drop in felony property crime while also controlling for so many social and economic factors. It's also one of the few studies to look at the strategy on a large scale, rather than a neighborhood or community level.

Broken windows policing assumes that serious crime can be reduced by strongly enforcing minor crimes such as graffiti, property damage, prostitution, public drunkenness and the like. It has been the subject of heated debate, with many police agencies adopting it and critics charging it leads to police harassment.

Previous studies have tended to focus on single jurisdictions, and haven't been able to discount numerous other possible factors when they discovered drops in serious crime.

This new study compared both misdemeanor arrests and misdemeanor
charges filed to the overall number of arrests and charges. More misdemeanor arrests and charges were taken to indicate a local law enforcement tendency to engage in broken window policing. That tendency was then compared to the felony property crime rate to see if a link existed.

"We've tested the spirit of the broken windows theory, and we've found a relationship between targeting misdemeanors and reducing serious crime," says John L. Worrall, the CSU San Bernardino criminal justice professor who authored the study.

Worrall cautions that the focus of this study was finding a statistical link between enforcing minor crimes and a drop in serious crime. So it doesn't conclusively prove a cause and effect relationship, and it doesn't estimate how much of a drop in crime is seen when a community pursues a broken windows strategy.

"What makes this study unique is all the other factors we controlled for, and that even after we did that we still found a strong statistical relationship between broken windows policing and a reduction in serious crime," Worrall says. "This is by no means the last word on the broken window theory, but it is an important contribution."

The study controlled for a number of other factors known to influence the serious crime rate, including: 1) deterrence - the probability of being arrested for a property crime and the percentage of people currently in custody, 2) economics - the per-capita welfare and unemployment rates, and 3) demographics.

More information is available by contacting John Worrall at (909) 880-7741 or Matthew Newman, director of the California Institute for County Government, at (916) 324-0796. The report is available online at the institute's website at www.cicg.org.

Additional media assistance is available by contacting CSUS public affairs at (916) 278-6156.

Full report (pdf)

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