The government may have to postpone the roll out of satellite tracking of offenders after a study uncovered serious technology flaws.
A study commissioned by the Ministry of Justice reveals that the signal could be lost and people could remove their ankle tags and leave them behind.
The report (pdf) says that in ideal conditions the technology was capable of finding the exact location of a tracked offender. But the signal could be distorted if an offender entered a building or a street with tall structures.
Offenders determined to commit crime could remove their tags or leave their tracking units behind, even though this behaviour would be detected, the report reveals.
Satellite tracking trials were announced in July 2004 under plans to clamp down on crime. David Blunkett, the then home secretary, said tracking would act as a "prison without bars".
Greater Manchester, Hampshire, and the West Midlands were chosen to test the new technology in a two year trial, which ended in June last year. The hope was that it would help to deter offenders from breaking the law, as well as providing law enforcement agencies with extra intelligence about offender movement.
Equipment consisted of an ankle tag and a portable tracking unit, which offenders had to keep with them at all times. The tracking unit received GPS signals and monitored the offender's location.
The target groups chosen for satellite tracking were offenders serving time for sexual, violent, and domestic crimes, as well as prolific offenders.
Professor Stephen Shute, author of the report, found that 58 per cent of the tracked offenders were either recalled to prison, or had their community sentence revoked. Most of these were the prolific offenders who had been ordered to live in a hostel.
The satellite tracking trials cost £42 a day for each person. An offender would most usually be tracked for 72 days, at a total cost of some £3,000. But Professor Shute said the costs charged by the monitoring companies during the pilots are unlikely to reflect the costs associated with a national roll out.
A spokesperson for the Ministry of Justice told GC News: "We are currently considering the evaluation report, and the recommendations of a National Offender Management Service Working Group, on the future use of the satellite tracking of offenders in England and Wales.
"Satellite tracking was not used as a replacement to existing methods of supervision or licence conditions, but as an additional risk management tool to enhance public protection.
"It has been used to monitor offenders in other countries and the study was primarily evaluating whether satellite tracking could be implemented."
This article was originally published at Kablenet.
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