As noted above, there were noticeable differences between the characteristics
of the subjects at the two sites, as well as differences among subjects
within each site. A few variables were examined for their within-site
effects on whether an offender drove while suspended.
In general, the small number of cases in each site limited the ability
to identify statistically significant relationships. Thus, the patterns
described below must be regarded only as suggestive of a relationship.
Based on the median annual household income associated with the offender's
zip code, income level did not appear to be a factor in whether Bergen
County offenders drove during their suspension. Among all Milwaukee
subjects, the prevalence of driving during the suspension period was
higher among subjects living in areas with median annual incomes less
than $25,000 (73 percent vs. 45 percent). With regard to gender effects
on driving while suspended, 3 of the 6 female Milwaukee subjects drove
during at least one of the during-suspension observations; the other
3 were not observed traveling. Nine of the 36 Bergen County offenders
were female; the female subjects were less likely than male subjects
to be observed traveling (44 percent vs. 70 percent), and also less
likely to drive when traveling (25 percent versus 37 percent). In Bergen
County, 21-25 year-old offenders were less likely than other offenders
to drive when traveling (14 percent vs. 44 percent). However, this was
not the case among Milwaukee offenders.
Although only 6 Bergen County subjects had had a prior license suspension,
these offenders were less likely than other subjects to drive while
suspended (20 percent vs. 39 percent, based on subjects who were observed
traveling). In Milwaukee, however, 67 percent of subjects had had a
prior license suspension, and these subjects were more likely than other
subjects to drive while suspended (82 percent vs. 62 percent, based
on subjects who were observed traveling). Almost half the Milwaukee
subjects were already serving a license suspension when arrested for
DWI, and these subjects were much more likely than other subjects to
drive while suspended (81 percent vs. 68 percent, based on subjects
who were observed traveling).