The reports investigate similarities and differences in risk factors for offending
of boys and girls, for early onset (before age 17) and for frequent offending,
and compare criminal careers of males and females in the same family. The research
used data collected in the Cambridge Study in Delinquent Development, which
is a prospective longitudinal survey of London boys from age 8 to age 46. The
risk factors associated with offending by the boysí brothers and sisters
were analysed and compared to the results obtained for the study boys themselves.
KEY FINDINGS
The prevalence
of convictions for criminal offences was much higher for brothers (at 44%)
than for sisters (12%).
The type of
offence varied between brothers and sisters. Burglary and theft of vehicles
were more prevalent for brothers; shoplifting and deception offences for sisters.
Although important
risk factors for brothers and sisters were similar, there were some gender
differences. For example, socio-economic and child-rearing factors (such as
low family income and poor parental supervision) were more important for sisters,
and parental characteristics (such as nervous fathers and mothers) were more
predictive of offending for brothers.
Risk scores
predicted offending more accurately for sisters than for brothers. For example,
in predicting early onset offending, the proportion of sisters convicted increased
from 2% of those with no risk factors to 21% of those with 4ñ5 risk
factors compared with an increase from 9% to 40% for brothers.