Electronic Monitoring (Florida)

Program Goals/Target Population

The Florida Department of Corrections (DOC) approved the use of Electronic Monitoring (EM) in 1987 to track offenders, to increase compliance with the terms of offenders’ release into the community, and to thereby reduce recidivism. Increasingly, the use of EM targets sex offenders and violent offenders. As of June 2009, 2,392 of Florida’s 143,191 offenders under community supervision were being monitored through EM.


Program Description

EM has emerged as an important tool around the Nation in the handling of offenders, particularly sex offenders. According to the most recent Interstate Commission on Adult Offender Supervision (ICAOS 2006) GPS Government Survey, 23 States currently have some sort of GPS monitoring program for sex offenders. Florida was an early adopter of the technology, with its legislature approving the use of EM in 1987. In 2005, the Jessica Lunsford Act (JLA) was signed into law in Florida, introducing new provisions and increased penalties, including that certain sex offenders be subject to EM for life. The JLA also included appropriations to increase the number of EM units available. As a result, the number of offenders monitored by EM roughly tripled, to reach 2,392 as of June 2009.


The first type of EM adopted—introduced into the Florida Department of Corrections (FDOC) in 1988 for offenders sentenced to house arrest—was a radio frequency (RF) system. This type of unit can be used to indicate whether an offender on house arrest is at home. The equipment consists of a tamper-resistant small transmitter worn by the offender. The transmitter communicates with a small receiving unit tied into the phone landline. The receiving unit notifies a monitoring station if the signal is lost; if so, the probation officer is notified. RF systems can be programmed to take work or religious schedules into account allowing offenders to be off-site at predetermined times. Officers can also use a "drive by" monitoring device to verify the location of the offender, whether at home, at work, or in treatment as scheduled. An RF unit costs about $1.97 per day (Bales et al. 2010). A decreasing number of offenders in Florida are tracked through RF systems, dropping to 99 in FY 2008–09 (Bales et al. 2010).


The second system, active GPS monitoring, was introduced into use in 1997. This technology depends on a network of satellites to triangulate the offender’s physical location. The equipment consists of a tamper-resistant bracelet worn by the offender and a tracking device carried by the offender. The tracking device uses transmissions received from the satellites to calculate the offender’s position and transmits the data to a monitoring center through a cell phone system. This information is transmitted in a slightly different fashion by passive and active GPS systems. The passive GPS system stores and transmits data at appointed times to the monitoring center. In contrast, the active GPS system transmits information in near “real time” on the individual’s location to the monitoring center. This near real-time transmission allows the center to alert the probation officer immediately when a violation occurs. Both GPS systems can be modified so that certain zones are excluded (such as schools or other places where children congregate) or included (such as a work zone). They also provide information on where an individual has been throughout the course of the day and when the offender was at the different locations. The passive GPS system costs about $4.00 per day (Florida Senate Committee on Criminal Justice 2004); the active system costs about $8.94 per day (Bales et al. 2010). While the active GPS equipment is the more expensive of the two, the total cost of operating the passive GPS equipment is almost double that of the active GPS system when staff costs are included. Florida stopped using the passive GPS in 2006 because of cost considerations (NIJ 2011). All of Florida DOC offenders are monitored with active GPS units.


Offenders placed on EM can be required to reimburse FDOC for the costs of the EM equipment. Offenders can be charged with violation of probation conditions for nonpayment of fees as imposed by the court. The department also has the right to charge offenders for damaged equipment.


Additional Information

To understand perceptions of people involved with EM, Bales and colleagues (2010) conducted interviews with probation officers and administrators involved in overseeing EM programs and offenders on EM, as well as offenders being monitored with EM. Administrators reported viewing EM as a tool for probation officers to do their job, not as a substitute for personal contact. Offenders and officers differed in their perceptions of how EM affected the likelihood of absconding. Eight-five percent of offenders reported that EM did not affect the likelihood of absconding, while 58 percent of officers thought that EM reduced the risk of absconding.


Most of those interviewed reported that EM affected offenders’ lives in negative ways. Forty-three percent of offenders and 89 percent of officers reported that EM had a negative impact on the offenders’ families. Also, offenders reported feeling a sense of shame and unfair stigmatization because, in large part, of the association of EM with sex offenders. Almost all offenders and officers reported their belief that EM makes it difficult for offenders to find and keep a job. EM, however, did not affect the ability of offenders to find housing. And despite the negative drawbacks associated with EM, most offenders (88.4 percent) reported preferring EM to incarceration.

Intervention ID: 
14 to 100

Study 1

Bales and colleagues (2010) used a mixed methods approach to examine the impact of Electronic Monitoring (EM). The treatment sample consisted of more than 5,000 medium- and high-risk offenders who were placed on EM at some point in their community supervision (low-risk offenders were excluded from the sample); a control group comprised more than 266,000 medium- and high-risk offenders not placed on EM over a 6-year period. The majority of the sample of offenders was male and white, with ages ranging from 14 to over 38 years. Current offenses of offenders included sex offenses, robbery, burglary, and other violent offenses.

Data was collected for the period of June 1, 2001, through June 30, 2007 from the Florida Department of Corrections Offender-Based Information System. To address the impossibility of random assignment to treatment or control conditions, propensity score matching was used to develop equivalency in the EM and non–EM groups to avoid selection bias. Cox proportional hazards routines were used to analyze data, and the propensity score was used as an inverse weight.

For the qualitative component, researchers conducted interviews with a convenience sample of 36 probation officers, 20 administrators, and 105 offenders who were invited to participate in the project during their regularly scheduled office visits. Interviews lasted 30 to 45 minutes. The data was collected to make a qualitative assessment of policies, practices, and processes in implementing EM.


Study 1

Risk of Failure

Bales and colleagues (2010) found that, compared with the control group on other forms of community supervision, Electronic Monitoring (EM) reduced the risk of failure by 31 percent. GPS was slightly more effective in reducing rates of failure to comply than radio frequency (RF) systems; more specifically, for GPS monitoring there was a 6 percent improvement in the hazard rate for reducing supervision failure compared with RF monitoring.

EM had a greater impact on sex, property, drug, and other types of offenders than on violent offenders, though the effect remained significant for EM supervision of violent offenders compared with other forms (non-EM) of community supervision. There were no significant differences in the effects of EM across different age groups or for the effect of EM for different types of supervision.