Aims: This study, conducted within a driving under the influence (DUI) court intervention, evaluated the degree to which removing electronic monitoring (EM) and/or mandatory vehicle sales requirements increased rates of post-sentence traffic violations among repeat DUI offenders.
Design: Randomized trial.
Setting and participants: A total of 477 repeat DUI offenders entering the Driving under the Influence of Intoxicants (DUII) Intensive Supervision Program (DISP), Multnomah County, Oregon.
Intervention: Subjects were randomized into four intervention groups. Group 1: standard DISP with EM and vehicle sales requirements; group 2: standard DISP with mandatory vehicle sale, but without EM; group 3: standard DISP with EM, but without mandatory vehicle sale; and group 4: standard DISP without EM or mandated vehicle sale. Standard DISP includes treatment for alcohol abuse and dependence, polygraph testing, regular court appearances, and probation or court-based monitoring.
Measurements: The risk of re-arrest for traffic violations was compared among the four groups using hazard ratio estimates from complementary log-log regression models.
Findings: Compared with group 1, subjects in group 2 initially had increased re-arrest risks, but this effect dissipated within 3 years of entering DISP. Group 3 subjects had a 96% increase in re-arrest rates. Group 4 subjects had smaller increased risks than predicted, with re-arrest rates similar to those of group 1 at the end of the follow-up period.
Conclusions: Although some of the findings suggest that mandatory vehicle sales may deter future traffic violations, inconsistent results across groups make this finding equivocal. Positive effects of EM, while large in the short term, appear to have a relatively small long-term value in reducing traffic arrest rates.