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Offender Wide Area Continuous Electronic Monitoring Systems: Executive Summary

NCJ Number
Date Published
6 pages

This report discusses the technical, theoretical, and computational problems associated with wide-area continuous electronic monitoring of offenders.


These second-generation systems make it possible to track individuals in places other than their homes and workplaces. Thus, the systems tighten the supervision of parolees and probationers while increasing public safety. The present research focused on identifying radio frequency location methods to apply to second-generation monitoring systems and on analyzing the effects of reflected signal on the solutions to the positioning problem. The analysis suggested the desirability of five goals for these systems. First, the system should be able to determine the offender position with accuracy of 50 meters 67 percent of the time and 150 meters 95 percent of the time. Second, the system should be able to track the offender’s position within the specified accuracy at all locations that wireless communications can reach. Other proposed goals include making geolocation information available in real time, having a locator tag that can detect tampering and alert the monitoring center, and giving the offender an audible signal if the locator device is out of communication range. The analysis concluded that exploiting emerging infrastructures and geolocation technologies by the private sector is likely to lead rapidly toward the development of the new systems and that educating professionals, entrepreneurs, and the public about the systems’ benefits could stimulate this effort.

Date Published: January 1, 2000