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Use of Global Positioning Satellite (GPS) System Monitoring

I. INTRODUCTION Over the last two decades, electronic monitoring has achieved acceptance within the correctional community and other areas of criminal justice. In the mid-2000’s global positioning satellite systems (GPS) were introduced, bringing electronic monitoring to a new level where client movement in the community can be tracked in real time. This technology has become well-accepted by the public and by legislators, who believe that GPS monitoring provides greater levels of accountability and control for offenders in the community. GPS monitoring has also proven to be an important tool to monitor offenders in the community in lieu of jail, allowing offenders to remain in the community working, receiving treatment, paying taxes, and supporting their families, while still being under a level of correctional control. Additionally, GPS has been used to improve the supervision and monitoring of higher risk offenders.

II. BACKGROUND GPS units are transmitters usually worn on the ankle. The GPS system will designate locations where the offender is and is not permitted to be, using a computer program that alerts supervisors when the location is entered and exited. Active or continuous signaling GPS transmits the offender data to authorities in “real time,” although active GPS units may have problems with losing the satellite signal, particularly indoors or in obstructed areas. A passive GPS monitoring system maintains a log of the offender’s location throughout the day, and landline or cellular telephones transmit a summary of the data to staff the following day.

Offenders are placed on GPS as a condition of pretrial release or as part of a sentence in lieu of jail. Additionally, sex offenders, domestic violence offenders, offenders on work release or under house arrest, and high risk gang and violent offenders may be required to be monitored by GPS as a condition of their supervision.

Although GPS supports effective monitoring and supervision by parole and probation departments and provides significant cost savings compared with incarceration, studies have been limited regarding the effectiveness of electronic monitoring to deter future criminal behavior. Two recent studies of offenders in Florida and California show electronic monitoring programs improve compliance with the conditions of supervision. The California study of high risk sex offenders on electronic monitoring also showed better outcomes for recidivism (re-arrest, reconviction, or reincarceration) (Bales et al., 2010; Development Services Group, 2012; Gies et al., 2012).

A recent meta-analysis of 12 useable electronic monitoring studies found that although “electronic monitoring to offset jail time” had no impact on crime outcomes, it did produce a positive return on investment for dollars spent on the program (Drake et al., 2009). GPS may achieve better outcomes if coupled with other wraparound services such as employment readiness, cognitive behavioral therapy, and substance abuse treatment. A 2000 study looking at measures other than recidivism found that electronic monitoring did not induce more compliance with curfews but did improve treatment attendance, indicating that secondary goals might also be achieved with the sanction (Bonta et al., 2000).

Allowing offenders to complete their sentence in the community rather than in jail, receiving treatment and maintaining community ties, may reduce the re-entry barriers facing offenders serving their sentence in jail, but this needs further study. In addition, more comprehensive research is needed to analyzes the use of technology with and without wraparound services as well as to determine the long term impact electronic monitoring has on recidivism.

III. STATEMENT OF PRINCIPLES The most intensive community correctional resources, such as GPS monitoring, should be directed at offenders in lieu of custody or as a condition of supervision for those at higher risk to re-offend. A large body of corrections research indicates that lower risk offenders who are supervised at enhanced levels re-offend more frequently and have overall higher recidivism rates than similar offenders supervised at lower risk levels, so GPS should not be used as a condition of probation or parole for this group.

GPS monitoring is a supervision and containment tool. It provides more information to staff about an offender’s daily activities, helps determine if offenders have violated specific supervision requirements, and may provide information useful in investigating possible criminal or violation behavior. It may also improve compliance with other supervision requirements, such as attending treatment.

A significant amount of GPS data is generated every day, and it is virtually impossible to analyze everything. New software has been designed to analyze behavior patterns and movement. The successful implementation of this software will have a significant impact on effective utilization of GPS.

The major benefit of GPS systems to the public has been a cost savings compared with incarceration while achieving similar results in terms of crime control. Additionally, keeping offenders in the community working and with their families, rather than in jail or prison, reduces disruption to offenders’ families and diminishes the inevitable barriers faced when returning to the community after incarceration.

IV. RECOMMENDATIONS The following recommendations are suggested regarding the use of GPS:

  • Educate criminal justice stakeholders about the value of GPS in lieu of incarceration for appropriate offenders who can safely serve their time in the community.

  • Couple the use of GPS monitoring with risk assessment to prioritize its use for more dangerous offenders in order to ensure greatest cost-effectiveness for limited public resources.

  • Pair GPS monitoring with needed services such as employment programs and substance abuse treatment to have the greatest impact on future criminal behavior.

  • Provide adequate staffing to ensure the information being collected by the GPS monitoring system is useful. GPS supervision requires significantly more time and attention than offender monitoring without GPS. Data analysis software should be encouraged for a more effective program.

  • If using active GPS, staff may receive alerts or violation reports requiring immediate response during any time of the day, on weekends, scheduled days off, and on holidays. The agency must plan for adequate staffing before deciding to use this type of monitoring.

  • Provide training to staff and stakeholders so that all are aware of how the equipment works, its limitations, and the kind of information that can and cannot be provided.

  • Encourage more research on GPS when used in lieu of incarceration or as a supervision tool.


Reviewed and adopted by the ICJA Board of Directors Date: March 10, 2014

References: Bales, William, Mann, Karen, Blomberg, Thomas, Gaes, Gerry, Barrick, Kelle, Dhungana, Karla, & McManus, Brian (2010). A Quantitative and Qualitative Assessment of Electronic Monitoring. Report submitted to the Office of Justice Program, National Institute of Justice, U.S. Department of Justice. Tallahassee, FL: Florida State University College of Criminology and Criminal Justice, Center for Criminology and Public Policy Research. Bonta, James, Wallace-Capretta, Suzanne, & Rooney, Jennifer (2000). Can electronic monitoring make a difference? An evaluation of three Canadian programs. Crime & Delinquency, 46(1), 61–75.

Development Services Group (2012). Home Confinement/Electronic Monitoring. Review prepared for the Office of Juvenile Justice and Delinquency Prevention (OJJDP), U.S. Department of Justice, Office of Justice Programs. Bethesda, MD: Author. Drake, Elizabeth K., Aos, Steve, & Miller, Marna G. (2009). Evidence-based public policy options to reduce crime and criminal justice costs: Implications in Washington State. Victims and Offenders, 4, 170–196.

Gies, Stephen V., Gainey, Randy, Cohen, Marcia I., Healy, Eoin, Duplantier, Dan, Yeide, Martha, Bekelman, Alan, Bobnis, Amanda, & Hopps, Michael (2012). Monitoring High-Risk Sex Offenders with GPS Technology: An Evaluation of the California Supervision Program, Final Report. Bethesda, MD: Development Services Group.

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