Another difference is pointed out by George Kelling, the Rutgers University academic who is the most influential exponent of the broken windows theory.

ECONOMIST: Crime

They are not that way anymore and we made the changes with the CompStat program, the broken windows theory and with very, very good leadership.

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One reason may be that, as the broken-windows theory suggests, law-abiding folk returned to the streets.

ECONOMIST: Policing

The broken-windows theory holds that all disorder creates crime.

ECONOMIST: Policing

It was an application of what would become famous as the "broken windows" theory, which held that even small signs of disorder would, if left untended, breed further disorder, crime and fear.

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Street stops increased substantially in New York in the mid-1990s, when, faced with overwhelming crime, then-Mayor Rudy Giuliani made stop and frisk an integral part of the city's law enforcement, relying on the "broken windows" theory that targeting low-level offenses helps prevent bigger ones.

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