Graffiti on the walls, trash in the street, bicycles chained to a fence, all resulted in a decline in how people behaved in a series of experiments.
A bit of litter or graffiti didn't lead to predatory crime, but actions ranging from littering to trespassing and minor stealing all increased when people saw evidence of others ignoring the rules of good behavior, Dutch researchers report in Thursday's online edition of the journal Science.
In normal behavior most people try to act appropriately to the circumstances, explained lead author Kees Keizer of the faculty of behavioral and social sciences at the University of Groningen, Netherlands. But some tend to avoid effort or seek ways to gain for themselves.
Things like littering an area or applying graffiti change the circumstances by indicating that others are not behaving correctly, which weakens the incentive for people to do the right thing.
I first encountered this idea in a book called The Tipping Point, by Malcolm Gladwell, in which this theory -- called "The Broken Window theory" -- is discussed in depth.
It makes sense. People adapt to their surroundings. When they start seeing disorder, neglect, anarchy, chaos, lack of consensus, failure, decay and dysfunction, they fit right in -- and take advantage of the lack of order to advance their own agendas at the expense of others.