Broken Windows Theory Passes the Test

To conduct a real life experiment with the theory, 17 of Lowell, MA's crime "hot spots" were cleaned up while another 17 were left alone. Researchers found a 20% dip in crime where conditions were improved.

1 minute read

February 11, 2009, 7:00 AM PST

By Judy Chang


"'In traditional policing, you went from call to call, and that was it - you're chasing your tail,' said Lowell patrol officer Karen Witts on a recent drive past a boarded up house that was once a bullet-pocked trouble spot. Now, she says, there appears to be a solid basis for a policing strategy that preemptively addresses the conditions that promote crime.

Many police departments across the country already use elements of the broken windows theory, or focus on crime hot spots. The Lowell experiment offers guidance on what seems to work best. Cleaning up the physical environment was very effective; misdemeanor arrests less so, and boosting social services had no apparent impact.

Such evidence-based policing is essential, argues David Weisburd, a professor of administration of justice at George Mason University. 'We demand it in fields like medicine,' Weisburd said. 'It seems to me with all the money we spend on policing, we better be able to see whether the programs have the effects we intend them to have.'

And this particular study, he said, is 'elegant' in how clearly it demonstrated crime prevention benefits."

Monday, February 9, 2009 in The Boston Globe

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