The ‘broken window theory’ may be true

If you're walking by a wall covered with graffiti, are you also more likely to litter? The Broken Window Theory, crystallised in a 1982 article in the Atlantic by political scientist James Q. Wilson and criminologist George L. Kelling, posits that the environment has a significant effect on whether people engage in anti-social behaviour. But there's been little empirical research on just how "broken windows" lead to social disorder and crime – until now, says Science magazine.

In a series of experiments reported in a paper published online by Science, researchers at the University of Groningen in the Netherlands found that if people see one norm or rule being violated (such as graffiti or a vehicle parked illegally), they're more likely to violate others – such as littering, or even stealing.

In one setup, for example, the experimenters attached useless fliers to the handles of bicycles parked in an alley that had a sign on the wall forbidding graffiti. There was no trash can in the alley. The experimenters covertly watched how many people tossed the fliers on the pavement or put them on another bike rather than pocketing them for disposal. On another day, they set up the same condition in the same place, except with graffiti on the wall. The results were striking:

When there was no graffiti, a third of 77 cyclists tossed the flier away; but more than two-thirds littered after the graffiti was applied.

In another experiment involving a €5 note left sticking out of a mailbox, 13 per cent of subjects pocketed it when the mailbox was in a clean environment, compared with 23 per cent when there was trash around.

Auditory cues can also set the scene for disorder; four out of five cyclists littered their fliers when they could hear illegal firecrackers being set off, whereas barely half did so when it was quiet.

Kelling commends the experiments as "very tidy." He says that most earlier studies "dealt with correlation rather than causality" but that there is growing evidence for the broken window effect. A Harvard University study, reported earlier this year, found that scrupulous "situational prevention" in troubled neighbourhoods in Lowell, Massachusetts – in particular, added policing and cleanup – was more effective than social services or law enforcement in maintaining order.

The study demonstrates that disorder in the environment has a generalised effect, says social psychologist Robert Cialdini of Arizona State University, Tempe. That finding suggests government agencies can expect a big payoff from what he calls "relatively minor efforts, let's say, to keep the streets clean."

Source: Constance Holden, Study Shows How Degraded Surroundings Can Degrade Behavior, Science, Vol. 322, No. 5905, November 21, 2008.

For text: http://www.sciencemag.org/cgi/content/full/322/5905/1175a

For study: www.sciencemag.org/cgi/content/abstract/1161405

For more on Crime: http://www.ncpa.org/sub/dpd/index.php?Article_Category=14

FMF Policy Bulletin/ 16 December 2008