Imagine walking through a neighbourhood and seeing graffiti, litter, and shopping trolleys strewn about the place. Are these problems to be solved, or petty annoyances that can be ignored in the light of more serious offences? A new study suggests that the former is right - even the most trivial of transgressions can spread and spiral because their very presence stimulates more of the same behaviour. Through a series of stunning real-world experiments, Kees Keizer and colleagues from the University of Groningen have shown that disorder breeds more disorder. The mere presence of graffiti, for example, can double the number of people who litter and steal.
Their study provides strong support for the controversial Broken Windows Theory, which suggests that signs of petty crimes, like broken windows, serve as a trigger for yet more criminal behaviour. It follows that fixing small problems can prevent the build-up of bigger ones and the gradual decay of a neighbourhood. The idea was first proposed in a magazine article published in 1982, but soon became the basis of many a social policy.
