BRAINTREE, Mass. — A retired Braintree police detective accused of using department technology to track and harass his ex-girlfriend pleaded not guilty to a criminal harassment charge Friday.
Mark Sherrick was arraigned on the charge and released on his own recognizance.
Records obtained by 25 Investigates show Sherrick used the Braintree Police Department’s Flock camera system to search a license plate associated with his ex-girlfriend 1,049 times.
A department audit showed the searches began on Aug. 20, 2024, around the time the couple broke up, and continued into 2025. Court records allege the criminal harassment occurred in January and February 2025.
According to court records, Sherrick is also accused of placing a GPS device on the woman’s car and tracking it using a department-issued cellphone.
During Friday’s arraignment, prosecutors argued that Sherrick poses a potential danger to the alleged victim and said the allegations involve an abuse of his authority and the resources available to him as a detective.
“The allegations are quite serious in the case and the harm that it caused the alleged victim,” a prosecutor told the court. “It’s also a very strong case for the Commonwealth, and it’s especially egregious because the defendant before you, these allegations concern his abuse of authority as the resources he had available as a detective.”
Sherrick’s defense noted that he is a veteran and former police officer with no criminal history.
The woman reported the alleged conduct to police, and Sherrick was placed on leave. He later retired from the department on April 2, 2025, while the town was investigating his conduct.
The Town of Braintree previously said a third-party investigation determined Sherrick had misused police resources, including license plate searches, for a personal matter unrelated to a legitimate police operation or investigation.
25 Investigates went to Sherrick’s home last month after first learning about the charge, but no one answered the door.
Sherrick was ordered to have no contact with his ex-girlfriend and is due back in court next month.
This is a developing story. Check back for updates as more information becomes available.
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