82 Chapter 7
in violent crimes by youths has increased considerably in the last decade,
although overall the rate of violent crime has been static.
Locality
There are clear neighbourhood differences in delinquency rates that can-
not be entirely explained by social class or other socio-economic factors.
The architectural design of buildings on estates has been shown to have
some effect; the ability to keep an eye on people and the feeling of
responsibility for what has been termed ‘defensible space’ seem important.
At a broader level, the Isle of Wight/Inner London comparison found more
than double the rate of conduct disorders in the inner-city area compared
with a rural area, and this was mostly accounted for by psychosocial
family factors, such as parental psychiatric disorder, parental criminality
and family discord, with neighbourhood factors, such as poor schools, also
contributing. It has been suggested that where there are stable cohesive
neighbourhoods without too much change in those living there, the
social network inhibits crime. The Cambridge study found that convicted
juveniles who then moved out of a deprived area of inner London had
a lower reconviction rate than those who stayed, even when other risk
factors were controlled for.
Associated factors
Family
Size. Particularly in lower socio-economic groups, there is a strong asso-
ciation with large family size, with the number of brothers being more
influential than the number of sisters. Conversely, the delinquency rate
is considerably lower among only children.
Income. Low income is strongly associated with greater delinquency.
Criminality. Serious juvenile offences are particularly strongly associated
with a history of criminality in parents or siblings. Is this due to shared
genes, shared deprivation, or social learning? Twin and adoption studies
of adult recidivist criminals do suggest a substantial genetic influence.
Studies of juvenile delinquency also suggest a genetic influence, but
shared environmental effects generally seem equally important. There
are interactional effects at play. Thus, observational studies of early
adopted children show that the adoptive parents of children who had
criminal birth parents use twice as much harsh and physical punishment
as those of children who did not have this heritage, suggesting that child
temperamental differences elicited more harmful parenting.
Child-rearing experiences. Juvenile delinquency, like conduct disorder, is
strongly associated with lack of caring supervision and broken homes.
The emotional tone is frequently one of hostility and discord. There is
often a lack of house rules, and a low level of monitoring of the child’s
behaviour and feelings; parents respond infrequently to either desired or
deviant behaviour, so that any punishments are inconsistent and such