Electronic tagging is a form of surveillance that uses an electronic device affixed to a person.

In some jurisdictions, an electronic tag fitted above the ankle is used for people as part of their bail or probation conditions. It is also used in healthcare settings and in immigration contexts. Electronic tagging can be used in combination with the global positioning system (GPS), but for short-range monitoring of a person that wears an electronic tag, radio frequency technology is used.

The electronic monitoring of humans found its first commercial applications in the 1980s. Portable transceivers that could record the location of volunteers were first developed by a group of researchers at Harvard University in the early 1960s. The researchers cited the psychological perspective of B. F. Skinner as underpinning for their academic project. The portable electronic tag was called behavior transmitter-reinforcer and could transmit data two-ways between a base station and a volunteer who simulated a young adult offender. Messages were supposed to be sent to the tag, so as to provide positive reinforcement to the young offender and thus assist in rehabilitation. The head of this research project was Ralph Kirkland Schwitzgebel and his twin brother collaborator, Robert Schwitzgebel (family name later shortened to Gable).^[1][2] The main base-station antenna was mounted on the roof of the Old Cambridge Baptist Church; the minister was the dean of the Harvard Divinity School.^[2][3]

Reviewers of the prototype electronic tagging strategy were sceptical. In 1966, the Harvard Law Review ridiculed the electronic tags as Schwitzgebel Machine and a myth emerged, according to which the prototype electronic tagging project used brain implants and transmitted verbal instructions to volunteers. The editor of a well-known U.S. government publication, Federal Probation, rejected a manuscript submitted by Ralph Kirkland Schwitzgebel, and included a letter which read in part: "I get the impression from your article that we are going to make automatons out of our parolees and that the parole officer of the future will be an expert in telemetry, sitting at his large computer, receiving calls day and night, and telling his parolees what to do in all situations and circumstances [...] Perhaps we should also be thinking about using electronic devices to rear our children. Since they do not have built-in consciences to tell them right from wrong, all they would have to do is to push the 'mother' button, and she would take over the responsibility for decision-making."^[4] Laurence Tribe in 1973 published information on the failed attempts by those involved in the project to find a commercial application for electronic tagging.^[5]

In the U.S., the 1970s saw an end of rehabilitative sentencing, including for example discretionary parole release. Those found guilty of a criminal offense were sent to prison, leading to sudden increase in the prison population. Probation became more common, as judges saw the potential of electronic tagging, leading to an increasing emphasis on surveillance. Advances in computer-aided technology made offender monitoring feasible and affordable. After all, the Schwitzgebel prototype had been built out of surplus missile tracking equipment.^[6] A collection of early electronic monitoring equipment is housed at the National Museum of Psychology in Akron, Ohio.^[7]

The attempt to monitor offenders became moribund until, in 1982, Arizona state district judge, Jack Love, convinced a former sales representative of Honeywell Information Systems, Michael T. Goss, to start a monitoring company, National Incarceration Monitor and Control Services (NIMCOS).^[8] The NIMCOS company built several credit card-sized transmitters that could be strapped onto an ankle.^[9] The electronic ankle tag transmitted a radio signal every 60 seconds, which could be picked up by a receiver that was no more than 45 metres (148 ft) away from the electronic tag. The receiver could be connected to a telephone, so that the data from the electronic ankle tag could be sent to a mainframe computer. The design aim of the electronic tag was the reporting of a potential home detention breach.^[10] In 1983, judge Jack Love in a state district court imposed home curfew on three offenders who had been sentenced to probation. The home detention was a probation condition and entailed 30 days of electronic monitoring at home.^[11] The NIMCOS electronic ankle tag was trialed on those three probationers, two of whom re-offended. Thus, while the goal of home confinement was satisfied, the aim of reducing crime through probation was not.^[12]

The use of ankle bracelets, or other electronic monitoring devices, have proven to be effective in research studies and possibly deter crime.^[21]

Several factors have been identified as necessary to render electronic monitoring effective: appropriately selecting offenders, robust and appropriate technology, fitting tags promptly, responding to breaches promptly, and communication between the criminal justice system and contractors. The Quaker Council for European Affairs thinks that for electronic monitoring to be effective, it should serve to halt a developing criminal career.^[22]

The National Audit Office in England and Wales commissioned a survey to examine the experiences of electronically monitored offenders and the members of their family. The survey revealed that there was common agreement among survey respondents that electronic monitoring was a more effective punitive measure than fines, and that it was generally more effective than community service. An interviewed offender is credited with saying: "You learn more about other crimes [in prison] and I think it gives you a taste to do other crimes because you've sat listening to other people."^[23]

In 2006, Kathy Padgett, William Bales, and Thomas Bloomberg conducted an evaluation of 75,661 Florida offenders placed on home detention from 1998 to 2002,^[21] in which only a small percentage of these offenders was made to wear an electronic monitoring device. Offenders with electronic tagging were compared to those on home detention without. The factors thought to influence the success or failure of community supervision, including type of electronic monitoring device used and criminal history, were measured.^[24] The results showed that offenders who wore electronic tags were both 91.2 percent less likely to abscond and 94.7 percent less likely to commit new offenses, than unmonitored offenders.^[24]

The electronic monitoring of a person, on whom an electronic tag is fitted, does not physically restrain this person from leaving a certain area, nor does it prevent this person from re-offending — the primary aim of probation. Furthermore, the public perception of home detention is that it is a form of lenient punishment.^[25]

In the US in 1990, Ronald Corbett and Gary T. Marx criticized the use of electronic monitoring in a paper presented at the Annual Meeting of the American Society of Criminology, Baltimore. In the paper, which was later published in the Justice Quarterly, the authors described 'the new surveillance' technology as sharing some ethos and the information-gathering techniques found in maximum-security prisons thereby allowing them to diffuse into the broader society. They remarked that 'we appear to be moving toward, rather than away from, becoming a "maximum-security society".^[26] The authors acknowledged the data mining capacity of electronic monitoring devices when they stated that "data in many different forms, from widely separated geographical areas, organizations, and time periods, can easily be merged and analyzed".^[26]

In 2013, it was reported that many electronic monitoring programs throughout the US were not staffed appropriately.^[27] George Drake, a consultant who worked on improving the systems said "Many times when an agency is budgeted for electronic-monitoring equipment, it is only budgeted for the devices themselves". He added that the situation was 'like buying a hammer and expecting a house to be built. It's simply a tool, and it requires a professional to use that tool and run the program.' Drake warned that programs can get out of control if officials do not develop stringent protocols for how to respond to alerts and do not manage how alerts are generated: "I see agencies with so many alerts that they can't deal with them," Drake said. "They end up just throwing their hands up and saying they can't keep up with them." In Colorado, a review of alert and event data, obtained from the Colorado Department of Corrections under an open-records request, was conducted by matching the names of parolees who appeared in that data with those who appeared in jail arrest records. The data revealed that 212 parole officers were saddled with the duty of responding to nearly 90,000 alerts and notification generated by electronic monitoring devices in the six months reviewed.^[27]

• Eva Kaili, former Vice President of the European Parliament, was released to house arrest in her Brussels apartment with an electronic ankle bracelet in April 2023, after being detained in Haren Prison for 4 months as part of the Qatargate affair.
• English professional footballer Jermaine Pennant played a Premier League match in 2005 while wearing an electronic tag; he had received the tag for drunk-driving and driving while disqualified.^[28]
• Lindsay Lohan failed to appear at a mandatory hearing, and a warrant was issued for her arrest. The judge ordered Lohan to wear a SCRAM bracelet, an electronic device that monitors the sweat for alcohol and alerts authorities if prohibited substances are consumed.^[29]
• Roman Polanski, one of the most famous fugitives from American justice in the world, was arrested in 2009 in Switzerland. The terms of his release included $4.5 million bail, house arrest wearing an ankle bracelet at his chalet, known as Milky Way, in the Swiss ski resort of Gstaad, after having spent sixty-seven days in a Zürich detention centre.^[30]
• Bernard Madoff, the financier accused in a $50 billion fraud case before trial was ordered under house arrest, with electronic monitoring, and posting $10 million bail against his $7 million Manhattan apartment, and against his wife's homes in Montauk, NY, and Palm Beach, FL.^[31]
• Dr. Dre (Andre Young), American rapper and record producer, was arrested in 1992 for assaulting record producer Damon Thomas and later pleaded guilty to assault on a police officer, eventually serving house arrest and wearing a police monitoring ankle bracelet.^[32]

• Automatic vehicle location
• Decarceration in the United States
• Electronic monitoring in the United States