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Probation, Auto Ignition Interlocks and Drunk Driving Offenses

NCJ Number
133926
Journal
Journal of Offending Monitoring Volume: 4 Issue: 1 Dated: (Winter 1991) Pages: 8,10-12,14-15,28
Author(s)
J E Guffey; M G Neithercutt; P Zajac
Date Published
1991
Length
7 pages
Annotation
Data from 146 cases of driving under the influence in 3 municipal courts in Santa Clara County (Calif.) were used to examine the use and effectiveness of the ignition interlock in reducing recidivism.
Abstract
The same judge sentenced all these offenders to probation on the condition that they have the ignition interlock installed in their vehicle, usually for the approximately 36 months of probation. Results showed that the offenders had an average age of 35 years, with 34 percent aged 21-29 and 31 percent aged 30-39. One court had many Hispanic and Vietnamese offenders, while the other two had mainly white offenders. Eighty percent were males. Ninety-five percent chose either blood or breath tests to determine blood-alcohol content (BAC), and the average BAC was 0.16 percent. Licenses were generally restricted for 90-180 days, and the average interlock period was 32 months. Analysis of interlock printouts from 14 offenders found that 13 tried to start the car at the 0.05 to 0.10 BAC level, 10 at 0.10 BAC and above, and 3 at 0.20 BAC. By April 1989, only 2 of the 146 cases had been rearrested for driving under the influence; both had bypassed the interlock. This recidivism rate of 1 percent compares to a statewide figure of 40 percent and a national figure of 49 percent. Further research should gather national data on the effectiveness of the ignition interlock in reducing recidivism. Table and 16 references