People who have seen the thriller movie Disturbia released in 2007 may be able to remember the main character,Kale. Kale is able to move within only 30 meters radius from his house due to his wearing an electric bracelet. He is always monitored by the police, and the police are directly called out when Kale moves out of the 30 meters radius.
Similar to the Disturbia’s tracking system, Ministry of Justice in Korea which recognized serious status of sex crimes in the nation is carrying out a Global Positioning Satellite (GPS) tracking program for high risk offenders. The law was taken effect in September 2008, and the administration established a GPS probation office. Also, about 500 sex offenders went through this program.
Today, due to the occurrence of cruel sex crimes, the tracking system has become a social issue. Then people may have questions about how GPS tracking program technologies are designed in Korea.
Core Technology: Electric Tagging Device
Electric monitoring, also called, ‘Tagging’ allows monitor officials to confirm an offender quickly and easily at a specified location when he or she is required to be present. When an offender is placed in an electric monitoring program, a tamper-resistant electric device is attached to his or her wrist or ankle. The device transmits an electric signal indicating whether the offender has had any unauthorized absences or has tampered with the device.
Electric Tagging Devise attached to an offender consists of three equipments: electric bracelet, home monitoring unit, and portable tracking device. At timed intervals, devices attached to criminals send GPS signals and report their position back to a receiver, the control center. Electric bracelet is always attached to the offender’s ankle. While he or she is staying at his or her residence, home monitoring unit works all the time and sends GPS signals. When an offender moves outside of an allowed range he has to bring the portable tracking device with him in addition to the electric bracelet. If he leaves his residence without carrying the portable tracking device, the police will be alerted and the offender will be arrested.
Electric Bracelet:
- Transmits an identifying signal to a portable tracking device and a home monitoring unit.
- Main features: Weight 80g, 400Mhz RF communications, 100 percent water-proof, dual tamper detection.
Portable Tracking Device:
- Tracks offenders’ movements via GPS and cellular communications network.
- Main Features: Weight 150g, AGPS, voice calling with Probation Officer, automatic call receiving, 18-hour battery, water-proof, tamper detection.
Home Monitoring Unit:
- Confirms offender’s absence from home.
- Wireless Communications, double antenna, dual tamper detection.
Tracking Devices and GPS
GPS technology is the means to monitor the offenders for 24 hours a day. If an offender is to violate the conditions of an electric monitoring order, the GPS could pinpoint his or her location. The tracking devices attached to the offender sends GPS signals to mobile communications Network and to Central Monitoring Center. The signal then is finally delivered to the probation office.
None of the monitoring devices currently used can track an offender’s movements on real time. Rather, they simply confirm whether or not the individual is at an approved place at specific times. It transmits its signal at interval of two or three minutes. The minimum time of transmitting interval is 40 seconds. However, because the battery of the electric bracelet will soon go out sending the signal fast, the control center has set the interval time from two to three minutes. Depending on the tracking device’s location, the intervals can be lengthened. For example, if the offender is in basement or on subway, the signals will be delivered later than usual.
GPS of tracking devices are connected to more than three satellites; it covers the whole world and works 365 days. Besides GPS, there are three other technology methods which mobile company controls and supervises. Locating underneath the ground and inside the building is impossible only throughout GPS system. Locating error can happen within 10 meters. When the offender is at the underground or inside the subway, beacon device can sensor the signals. It plays a bridge role between the satellites and the offender’s Electric Tagging Device. Then there is PCELL and CELL. They take complementary measures by detecting the tagged offender’s location that GPS alone cannot access. Error range still exists nonetheless, it is better than to lose the tagged whereabouts.
Type of Offenders and Prevention of Crime by Tracking Device
In Korea, electric monitoring device system was established after an 11-year-old girl in Seoul? Yongsan area was raped and murdered by a neighbor in 2006. The law ensures real-time monitoring those who convict sex crimes twice, or who assault children under the age of 13. Currently, 150 sex offenders are now wearing the Electric Tagging Device. The system has been working since Sept. 2008. As previously mentioned, 500 sex offenders have worn ankle tracking device. The Ministry of Justice is under consideration of enlarging the subject matter of tagged offenders from sex offenders to convicted murderers and burglars.
Devices are water proof and if devices are destroyed by accident or with intentions, the tracking system alerts monitoring officials. The damage of the device is immediately notified to the center. The manager of GPS Probation Office, Kim Chang-yong said, “However, monitoring center cannot distinguish whether the offender is committing a crime or not. Nonetheless, warning signal is transmitted when the offender approaches near the banned zone which is children related place such as school, playground and day care center.” The first warning alarm is sent out to the probation office if the offender approaches the exclusion zone within 50 meters. The second warning alarm is then sent when the offender enters the exclusion zone.
Electric Tagging in the World
The Electric Monitoring Device was first developed by a group of researchers at Harvard University in the 1960s. It was first started in the 1980s in the United States. Currently, about 10 nations have adopted the electric monitoring system: the United States, the United Kingdom, Australia, Sweden, China, Korea, and etc. The law applied to criminal cases which tag the device varies from country to country. In some countries, offenders who are likely to abuse drugs and commit crime again after they are released are categorized to be tagged too and in other countries only sex offenders are to wear the device.
Prospect of Electric Bracelet
Although new technologies are mounted in the system, some reporters and experts raised a question: Can technologies of GPS tracking program recognize sex offenders’ specific behaviors?
Kim Chang-yong commented on that, “That is a problem of the system. We can locate them but cannot recognize their actions. Portable Tracking Device combined with visual telephone technology could be one of the answers. Maybe visual telephone system between probation officers and sex offenders can assist to know the criminals’ situations.”
As previously described, GPS Tracking System has been enforced a year and two months ago. Statistics of the specific effects of the GPS Tracking System will be proved in the next five to 10 years. Continuous technical development to prevent and decrease sexual abuse is expected.