MINNEAPOLIS — The Minnesota Department of Corrections uses electronic monitoring to track high-risk sex offenders, as well as other offenders who are finishing out their sentences on supervised release. Thousands of alerts are generated each month, and while most are harmless, strapping a GPS bracelet on an offender’s ankle does not guarantee he or she will stay out of trouble.

Just last month, a St. Paul man who was on electronic monitoring while on a prison furlough was charged with sexual assault. Authorities said Curtez Deshawn Graham, 18, cut off his ankle bracelet, returned to the home of his prior burglary victim, and raped her. According to the criminal complaint, Graham told police he went to the house to scare the woman and send her a message.

But corrections officials say incidents like this are rare. Spokeswoman Sarah Russell said in the vast majority of cases, the devices are successfully used to verify offenders’ locations.

Russell said corrections officials can’t talk about the details of Graham’s case because he was originally sentenced as a juvenile. But she did say officials have found no evidence that policies were not followed in any recent events or that a policy revision is necessary.