A former police officer in Texas who is believed to be one of the most prolific Flock misusers in the country used the technology to track his ex-girlfriend and her romantic partners and jeopardized an open manslaughter case because of his misconduct, the district attorney who prosecuted him told USA TODAY.

Zachary Klein, an 11-year veteran of the Lufkin Police Department, was sentenced on Sept. 30 to five years in prison, five weeks after a USA TODAY investigation found he used his agency's automated license plate reader cameras to monitor individual cars thousands of times.