Use of Electronic Offender-Tracking Devices Expands Sharply Overview The number of accused and convicted criminal offenders in the United States who are monitored with ankle bracelets and other electronic tracking devices rose nearly percent over 10 years, according to a survey conducted in December by The Pew Charitable Trusts.
More than , people were supervised with the devices in , up from 53, in All 50 states, the District of Columbia, and the federal government use electronic devices to monitor the movements and activities of pretrial defendants or convicted offenders on probation or parole. How electronic tracking works Correctional authorities use ankle bracelets and other electronic tracking devices to increase compliance with the conditions of pretrial release, probation, or parole among accused and convicted offenders residing in the community.
GPS systems can continuously track offenders in real time, identifying their movements and whereabouts by transmitting location information to monitoring centers and triangulating signals from satellites and cellular towers. Earlier approximations have varied widely. For example, one study estimated that more than 90, GPS units were in use nationwide in ,6 while the federal Bureau of Justice Statistics reported that the figure was about 25, the same year. The former did not include a detailed methodology and did not indicate whether it counted only active monitoring devices or inactive ones as well; the latter did not count defendants on pretrial release and relied on the voluntary participation of state and local court and supervision agencies, many of which did not submit information.
Seven of the largest companies responded, representing an estimated 96 percent of the market. The survey excluded devices used in immigration cases because those offenses are generally considered civil in nature and Pew sought instead to measure electronic tracking in the criminal justice system. To avoid doublecounting people who may have been tracked electronically at multiple points in one year, it asked companies to count the number of devices in use on a single day—Oct.
Manufacturers do not have access to information about the accused and convicted offenders supervised by their products. GPS drove the increase in electronic tracking The number of accused and convicted criminal offenders monitored with electronic tracking devices in the United States increased percent between and , from approximately 53, to more than , Extrapolating from the 96 percent market share of the companies that participated in the survey, the total probably exceeded , The survey also shows that a sharp increase in the use of GPS technology accounted for all of the year growth in electronic tracking, more than offsetting a decline in the use of RF devices.
In , manufacturers reported that about 88, GPS units were being used for supervision of accused and convicted offenders, a thirtyfold increase from the roughly 2, reported a decade earlier.
By contrast, the number of active RF units fell 25 percent, from more than 50, to below 38, These findings are consistent with published studies that suggest RF devices are giving way to technology that can track offenders in real time. Nationally, nearly 7 million people were in prison or jail or on probation or parole at the end of , but individuals tracked using electronic devices in represented less than 2 percent of that total.
More than , people were tracked with the devices on a single day in , up nearly percent from the 53, reported on the same day in A sharp increase in the use of GPS technology accounted for all of the growth, more than offsetting a 25 percent decline in the use of RF systems. Despite the overall expansion of electronic tracking, however, the technology remains relatively rare in U. Editorial assistance was provided by Carol Hutchinson, Jennifer V.
Doctors, Bernard Ohanian, and Liz Visser. The project team thanks Kelly Hoffman and Jennifer Peltak for production, design, and web support. Lessons Learned August , , http: Community Corrections Resource , 33, https: Total includes offenders on probation and parole. To determine the market share captured by the survey, Pew consulted George Drake, an expert on offender-tracking technology, who estimated that the four manufacturers that did not participate each accounted for less than 1 percent of the total number of devices in use.
That manufacturer received a separate survey with instructions to exclude numbers for individuals monitored for immigration-related proceedings or violations, or any numbers associated with its ICE contract.
Figure does not include pretrial defendants who are released from custody while awaiting trial. William Bales et al.