A 'diver's watch' some view as a badge of honour

Prisoners allowed home under the extension of the electronic tagging scheme will have to wear a device the size of a diver's watch around their wrist or ankle.

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Prisoners allowed home under the extension of the electronic tagging scheme will have to wear a device the size of a diver's watch around their wrist or ankle.

Between the hours of 7pm and 7am, the tag, which weighs less than 2oz, (55g) acts as a modern equivalent of the prisoner's ball and chain.

It sends a continuous signal from a small radio transmitter to a receiving unit attached to the telephone in the person's home or hostel. The unit is able to set the limit within which the offender must remain during his hours of curfew.

By stepping outside the agreed area, usually the garden of the house or the grounds of the hostel, the offender sends a signal to a control centre managed by staff from the private security companies contracted by the Home Office to run the tagging schemes. Any attempt to tamper with the tag will also trigger the alarm.

During the day, offenders are free to come and go as they please. Home Office officials hope they will spend their time seeking work and rebuilding family relationships that may have broken down during their time in prison.

The two-tone grey waterproof tag must be worn at all times. It is usually concealed beneath a sock. The Ipswich Town footballer Gary Croft was obliged to wear his during a Football League game after he was released on home detention curfew while serving a prison sentence two years ago.

But some young people make no effort to conceal the plastic devices and there is increasing anecdotal evidence that they are seen as a badge of honour among teenagers.

There are 1,800 people on the home detention curfew scheme with a further 1,300 adults and 200 juveniles required to wear tags after being sentenced to curfew orders. A further 50 individuals wear tags as conditions of community punishments. The 1,300 inmates who will be released under the extension of the HDC scheme will wear tags for the final two months of their sentences.

Confidence in the tagging system, introduced under the previous Conservative government, is growing as fears of a high levels of reoffending in the period of early release have proved unfounded. It also a cheap and generally efficient way of controlling offenders.

But police are not yet convinced the devices are an effective crime deterrent for young offenders.