A 5-Euro note serves as bait in a sociological experiment. Credit: AAAS
Last month social scientists in the Netherlands empirically demonstrated a phenomenon observed by policymakers and law-enforcement officials for years. When an envelope visibly containing a five-euro note was left hanging out of a mailbox on a sidewalk, 13 percent of the passersby snatched it up. When the same mailbox was covered in graffiti, however, more than double the number of the pedestrians (about 27 percent) stole the envelope.
Graffiti was not the only misdemeanor that fostered a cavalier attitude toward theft. When the ground near the mailbox was covered in litter, 25 percent of the subjects stole the envelope. These results are significant for both social and statistical reasons. Is a disorderly environment responsible for disorderly conduct?
Broken window theory (BWT), first proposed by James Wilson and George Kelling in 1982, holds that the presence of disorder — in the form of broken windows, litter, and graffiti — can encourage delinquent behavior. BWT promotes a “nip it in the bud” stance toward crime prevention: Fix small problems (like litter) before big problems (like theft) have a chance to occur. Former New York City mayor Rudy Giuliani was a loyal subscriber to the theory. He focused on small-scale issues like graffiti, prostitution, and squeegee men to influence, and ultimately drive down, crime in a seemingly unmanageable city.
Still, the veracity of BWT has always been in question. No rigorous study corroborated whether it was really responsible for the changes it purportedly caused. But these new findings by Kees Keizer, Siegwart Lindenberg, and Linda Steg (University of Groningen) show that ordinary people are in fact more likely to violate rules in situations where other rules — even completely unrelated ones — have already been broken. This might form the basis of a social model for understanding how disorder spreads.
The authors conducted six controlled field studies. In each experiment, one scenario provided an order condition (adherence to a contextual norm), while a second provided a disorder condition (a violation of a contextual norm). In all cases, violation of a contextual norm caused a significantly higher number of participants to break another rule. When a gate contained signs explicitly asking participants (a) not to walk through and (b) not to chain their bikes to the fence, 27 percent of the passersby walked through anyway. Compare this to 82 percent of the participants that walked through when another contextual norm was already violated — the chaining of bikes to the fence. One norm violation led to the violation of another.
“No, the results did not surprise us,” says Lindenberg. “What surprised us was the size of the effect.”
It’s not that good people turned bad, either. One goal simply surpassed another in importance. In the case of the mailbox, the desire for cash superceded the desire to behave appropriately, because others already hadn’t. “People are not bad. People are just subject to social influence,” Lindenberg says. An effective tip for crime prevention is to be aware of norm violations on all fronts. After all, says Lindenberg, “Even old grandmothers would do this.”
The Spreading of Disorder
Science December 12, 2008
Originally published January 8, 2009