Raleigh, N.C. — A Lee County man will be monitored by a Global Positioning System device for the rest of his life. Murnice Chandler was convicted on 21 counts of indecent liberties with a child and was sentenced Monday to 10 years in prison.

A law passed last year created the GPS program to track sex offenders, like Chandler. With old house-arrest bracelets, officers could only tell if an offender left the home. With GPS, they know where the person is at all times.

Superior Court Judge Allen Baddour ordered Chandler to be tracked by GPS. The judge would not comment on the case, but said the law makes the punishment automatic for certain sex offenders.

"That person is determined to be a recidivist, a sexually violent predator or to have committed an aggravated offense. Those are the three main categories," Baddour said.

Hannah Rowland, an administrator for the GPS program at the North Carolina Department of Correction, said there are 124 offenders wearing GPS devices. Among those, 40 will be wearing them for life, she said.

The device "allows us to know their whereabouts if needed," Rowland said.

Equipment carried at the ankle and waist communicates with satellites to give an offender's position. Probation officers receive updates on computer through cell phone signals. They get alerts when an offender goes where he or she is not supposed to go.

The system costs about $8.30 a day for each offender. It takes only a couple of correctional officers to track the GPS wearers across the state.

The GPS system does have trouble updating when offenders live in bad cell phone signal areas. In those cases, the equipment sends a report once a day when it is plugged in to charge its batteries.