McCormick, 29, said his troubles with GPS monitoring began soon after being fitted with an ankle bracelet in February 2017. Records show the tracker made by Boulder, Colo.-based BI Inc. was not communicating with the Department of Corrections’ Electronic Monitoring Center in Madison because of poor cellular reception at his grandmother’s house where he lived in rural Monroe County.

And even though police found him exactly where he was supposed to be, McCormick was taken to jail for about three days. As a result, he lost his job at his family’s restaurant.

Ten months later, McCormick was incarcerated again, this time for five days. Records from the Sparta Police Department show the arrest stemmed from McCormick allegedly being located next to a library — a zone off-limits for him — for an hour. McCormick said he only drove past it; his roommate, who was driving with him, confirmed his story.

McCormick’s difficulties persisted. This January, McCormick was briefly jailed on a warrant for allegedly tampering with the bracelet. A police report said McCormick showed them he had not tampered with it. He was later fitted with a new bracelet. Officials did not charge him with a crime — although tampering is a felony offense.

“It’s not just the people who are on monitoring devices (who are affected),” McCormick said. “It’s their family, their jobs, their social life.”

McCormick’s story illustrates broader flaws with Wisconsin’s GPS monitoring program, which relies on both cellphone and satellite service to track offenders.

The center reviewed data from a single month, May 2017, to more deeply explore the large volume of alerts being triggered by Wisconsin’s monitored offenders. In all, Wisconsin offenders in May generated more than 260,000 GPS alerts, 81,000 of which corrections officials sorted through manually.

The review found:

• The state monitoring center lost cell connection 56,853 times with 895 offenders that month — or an average of about 64 times per offender, according to DOC records.

• Most offenders on monitoring across the state experienced loss of satellite signal, generating 32,766 alerts — half of which were serious enough to be investigated.

• Of the 52 arrest warrants issued by the DOC monitoring center, service request records indicate 13 involved offenders whose equipment was having technical problems around the same time.

• DOC employees submitted 135 requests for technical problems with GPS tracking devices — 93 for charging or battery issues with ankle bracelets, 12 for signals lost, 14 for false tamper alerts.