we observe that the frequency of drug sales among
gang members is significantly higher in only one case
out of three (age 15 only and never gang members in
the second period), while in the periods in which the
transient members do not belong to a gang, the differences
from the never gang members are not significant.
During the years of gang membership, the
stable gang members always have a higher level of
drug sales than never gang members, and in some
cases than transient gang members.
In conclusion, the highest level of involvement in
drug sales is chiefly seen among stable gang members;
leaving the gang does not lead to a reduction in
this type of offence, though this might depend on the
age effect. Moreover, the results do not enable us to
establish that any of the three models is at work.