Monitoring high-risk sex offenders with GPS

In response to media attention and public demand, legislation increasingly mandates more stringent surveillance for sex offenders. This trend towards greater supervision resulted in the lifetime GPS monitoring of high-risk sex offenders (HRSO) in California. This study assesses the impact of the California Department of Corrections and Rehabilitation’s GPS program for HRSOs by employing a quasi-experimental design. The treatment group was drawn from all HRSO who were released from prison and placed on GPS monitoring in California. To identify comparison individuals likely to have pretreatment risk characteristics similar to those in the treatment group, a propensity score matching procedure was performed. The final sample included 516 subjects equally divided between the treatment and control groups. Data was assessed using Cox proportional hazards survival analysis clustering participants by parole district. Results showed the GPS condition was associated with significantly fewer parole registration and arrest violations, arrests, and convictions. These results are discussed in relation to other electronic monitoring research, the policy implications for the increasing use of this technology, and its effectiveness in reducing crime, prison populations, and ensuring public safety.