This paper reports an experiment in the state of North Carolina (NC), USA, to test the recurrence of DWI (driving while intoxicated) among four groups of second-time DWI offenders. All such offenders in NC receive a four-year hard licence suspension. At the end of the second year, they may apply for an administrative hearing, which has power to grant a conditional licence. Using data from the NC Driver History Files, a quasi-experimental design was used to examine the recidivism rates of the offenders in the following four groups: (1) Non-Applier Group, who never applied or completed the application process; (2) Denied Licence Group, who completed their applications, but were denied a conditional licence or refused the offer of a conditional licence with mandatory participation in the interlock programme; (3) Interlock Group, who obtained a conditional licence and had an ignition interlock installed on their cars; and (4) Conditional Licence Group, who obtained a conditional licence but were not required to participate in the interlock programme. The failure (recidivism) rates among these groups were 18.2%, 4.7%, 2.9%, and 5.2%, respectively. However, recidivism rates for the Interlock Group rose after full licences were restored to them and interlocks removed.
Abstract