In general the longitudinal studies reveal that gang
members display higher rates of juvenile delinquency
and drug use than non-gang members do,
and that joining a gang increases the frequency of
these behaviours. However, some discrepancy can
be seen among data on delinquency in the period
prior to gang membership; in some cases delinquency
rates have been reported to be similar to
those seen among youths who do not belong to a
gang, while in other cases higher rates have been
reported. In the first (1993) study by Thornberry
et al., for example, stable gang members displayed
higher rates of violent crime than non-gang members,
even during periods in which they did not
belong to a gang, while no difference in the rates of
such crimes was observed between transient gang
members and non-gang members.
Our aims were: