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Tale of Two Studies: Lessons Learned From GPS Supervision in California Corrections

NCJ Number
Corrections Today Volume: 77 Issue: 7 Dated: July/Auguest 2015 Pages: 20-22
Date Published
August 2015
3 pages

This paper describes and compares the results of two NIJ-funded evaluations of the California Department of Corrections' use of GPS (global positioning system) technology to monitor parolees.


One study involved high-risk sex offenders, and the second study focused on high-risk gang offenders. The evaluation of the sex-offender GPS monitoring program found that the risk of a sex-related violation was nearly three times as great for the traditional parole group compared to the GPS-supervision group. Similarly, the risk of arrests in general was more than twice as high for the traditional parole group. In contrast to the first study, the study of GPS for gang offenders found that the odds of technical and non-technical violations were greater among the parolees on GPS supervision; however, the GPS group was less likely to be rearrested overall (26-percent lower). It is important to note, however, that the overall parole program for sex offenders included a treatment element; whereas, the gang-offender group did not. Based on these findings, four recommendations are offerred. First, decide what type of offender will be placed on GPS supervision. Second, identify the phase of case processing in which GPS supervision will be used. Third, find ways to integrate supervision conditions with GPS technology; and fourth, define a minimum quantity of face-to-face supervision based on parolee risk level and the cost of traditional supervision. 1 table and 3 notes

Date Published: August 1, 2015