THE ROUGH GUIDE TO PSYCHOLOGYOf those people with a criminal record, one subgroup had only begun
to display criminal behaviour in adolescence (largely driven by peer
pressure and teenage rebelliousness) and had grown out of it by early
adulthood. In contrast, a second, far smaller, delinquent subgroup first
displayed signs of criminal behaviour in early childhood, sometimes
from as young as two or three. Their criminal tendencies worsened in
adolescence and continued throughout adult life. Moffitt and Caspi call
this type of offender life-course persistent.
Do broken windows really encourage crime?
The “broken window” theory of crime reduction argues that by
clearing up signs of social disorder, such as litter, graffiti and broken
windows, you help prevent the spread of undesirable behaviour. The
idea was given a high profile by Malcolm Gladwell in his best-selling
book The Tipping Point, in which he attributed the dramatic fall in crime
in New York in the 1990s to the zero-tolerance approach of the police
at that time. In 2008, the theory received the backing of a team of
Dutch psychologists led by Kees Keizer, after they contrived a series of
scenarios in which signs of orderliness were varied and the effect on
passers-by was observed and measured. For example, Keizer’s team
found that bicycle owners in an alley were more than twice as likely
to drop litter – a flyer attached by researchers to their handle bars – if
the walls were covered in graffiti. In another scenario, passers-by were
more likely to steal a money-containing envelope protruding from a
postbox if litter was on the ground, or graffiti was on the postbox.