One license plate. One thousand and forty-nine searches. That is what an audit of the Braintree Police Department’s Flock Safety system showed when Boston 25’s investigative unit obtained it: a detective running the plate of one woman, his former girlfriend, more than a thousand times, beginning on August 20, 2024, which the criminal complaint says was around the time the couple broke up.
Mark Sherrick, 56, now faces a criminal harassment charge. Court records say he also placed a GPS device on her car and tracked it using a Braintree Police Department cellphone. He retired from the department on April 2, 2025, during a third-party investigation into his conduct. He is presumed innocent.
For eighteen months, every Massachusetts community that voted to cancel its Flock contract heard the same objection from supporters of the cameras: that misuse is hypothetical, that audits exist, that the system is only as dangerous as the people using it. Braintree is the third Massachusetts department this month where the hypothetical turned out to have a name. This piece sets out what happened in each, what the law makes of it, and why the audit that caught Sherrick is the part worth paying attention to.
Braintree
The Town of Braintree confirmed the essentials in a statement to Boston 25: “The Town’s investigation, conducted by a third party, revealed that the former Detective misused police resources, including license plate queries, for a personal matter unrelated to a legitimate operational or investigative reason.”
The criminal complaint places the charged harassment in January and February 2025. The department’s own Flock audit places the plate searches starting the previous August. That gap matters, because it means the searching went on for roughly five months before the conduct that produced a criminal charge, and the department did not catch it during that time. POST Commission records indicate Sherrick had been disciplined previously for several violations, including harassment.
Braintree says it will not comment further while the criminal investigation is active. Mayor Erin Joyce and newly appointed Chief Robert Kilroy said the town is committed to “the proper, responsible use of all law enforcement tools.” Sherrick is due in court late this month.
Revere
Officer Michael Tiso accessed Revere’s Flock cameras more than a dozen times on four separate occasions to track his former girlfriend, Marissa Todisco, according to an internal affairs report obtained by the Boston Globe. The department’s investigation, opened after Todisco complained in December 2025, found he “violated department policies and use protocols” governing both the license plate reader system and the state’s criminal records database. He was suspended without pay. He is back at work.
Tiso denied to investigators that he used Flock to harass or follow her. Todisco had herself been charged in June with violating an abuse prevention order, and those charges were dismissed this month. “I completely feel there is an invasion of privacy of my family and God knows who else may be involved with me,” she said outside Revere City Hall.
Revere reported the matter to the POST Commission, which already had two 2020 misconduct findings against Tiso. Chief Maria LaVita said every search must be “connected to a legitimate, lawful purpose,” and the department has added software to flag unusual search activity and written a policy specific to plate readers. Revere is keeping its cameras.
New Bedford
A New Bedford officer has been accused of using Flock cameras to track and follow a former romantic partner, according to the New Bedford Light. That matter is the least developed of the three publicly, and we are not naming the officer while the reporting remains thin.
What the law reaches
Three separate bodies of law, and they do not line up neatly.
Criminal harassment, G.L. c. 265, § 43A, punishes anyone who “willfully and maliciously engages in a knowing pattern of conduct or series of acts over a period of time directed at a specific person, which seriously alarms that person and would cause a reasonable person to suffer substantial emotional distress.” The penalty is up to two and a half years in a house of correction, a fine of up to $5,000, or both. The statute expressly covers conduct carried out through electronic devices and systems, which is broad enough to include database searches. A thousand plate queries is a pattern by any reading, but the Commonwealth still has to prove the target knew and was seriously alarmed, which is why the charged window is narrower than the search history.
Stalking, § 43, is the more serious offense at up to five years in state prison, but it requires something the harassment statute does not: a threat made with intent to place the person in imminent fear of death or bodily injury. Covert surveillance with no threat does not satisfy it. That is the reason a case built on a thousand secret lookups is charged as harassment rather than stalking, and it is a genuine gap in the statutory scheme.
Unauthorized computer access, G.L. c. 266, § 120F, reaches a person who knowingly accesses a computer system without authorization. The maximum is thirty days in a house of correction. An officer with valid credentials who uses them for a forbidden purpose presents the harder version of that question, and it is the same problem federal courts wrestled with over the Computer Fraud and Abuse Act before the Supreme Court narrowed “exceeds authorized access” in 2021.
The criminal records database misuse found in Revere is its own matter. Access to the state’s criminal offender record information is governed by statute and regulation, with its own penalties for unauthorized dissemination, and it is a separate violation from anything involving a camera.
The audit is the story
Every one of these cases surfaced the same way: someone looked at a log.
That is the strongest argument for the cameras and the strongest argument against them at once. The systems record every query, the searcher, and the time, which means misuse leaves a trail that a paper-file era of policing never produced. Braintree’s audit did not merely confirm a complaint; it produced a number, 1,049, that no witness could have supplied.
But the trail only matters if someone reads it. In Braintree the searching ran from August 2024 and the town’s investigation came the following spring, after a complaint. In Revere the department added automated alerts for unusual search activity only after the internal affairs finding. Boston’s 2025 surveillance report, which we covered when it landed, disclosed that officers ran 11,004 Flock searches during the city’s pilot and that roughly half carried no case number linking the search to an investigation. Nobody was reviewing those in real time either.
An audit log that is examined once a complaint arrives is a record of what already happened. It is not a control.
What this does to the towns still deciding
Eighteen Massachusetts communities that we can document have ended or suspended Flock contracts, and the ACLU of Massachusetts counts twenty-five. The most common stated reason has been the national data-sharing question, which is about where the data goes. Braintree is about something narrower and harder to answer: what one authorized user does with the data at home.
No contract term fixes that. Boston’s contract said sharing was off and it was not. Braintree’s policy presumably required a legitimate purpose, and a detective ran one plate a thousand times anyway. The available responses are automated anomaly detection of the kind Revere has now installed, mandatory case numbers on every query of the kind Boston’s own auditor recommended, and independent review of the logs by someone outside the department.
H.3755, the bill that would have set statewide rules for license plate readers, cleared committee unanimously in March and died in Ways and Means. It contained an enforcement provision. Lawmakers are pushing new rules again this month. Whether any of it reaches a floor vote before the session ends is the practical question, and these three cases are now the argument for it.
Common questions
What is the Braintree officer accused of?
Criminal harassment. Court records and a department audit obtained by Boston 25 indicate former Detective Mark Sherrick searched one license plate tied to his former girlfriend more than 1,049 times beginning in August 2024, and placed a GPS device on her car tracked with a department phone. He retired in April 2025 during a town investigation and is presumed innocent.
Is using a police database to track an ex a crime in Massachusetts?
It can be. Criminal harassment under G.L. c. 265, § 43A covers a malicious pattern of acts that seriously alarms the target, including acts carried out electronically. Unauthorized computer access under c. 266, § 120F carries up to thirty days. Stalking requires a threat, which covert tracking alone does not supply.
How were these caught?
Through audit logs. Flock and similar systems record every search, the user and the time. In each case the record existed before anyone looked at it, and was examined after a complaint.
Is Revere still using Flock?
Yes. The department suspended the officer without pay, reported him to the POST Commission, added software to flag unusual searches and adopted a policy specific to plate readers.
How many Massachusetts towns have dropped Flock?
Eighteen that we can document from public announcements and reporting. The ACLU of Massachusetts counts twenty-five communities that have cancelled contracts or ended pilots.
Braintree facts, the 1,049 figure and the town’s statement from Boston 25 News, September 17, 2026, which obtained the court records and the department’s Flock audit. Revere facts from Boston.com and the Boston Globe’s review of the internal affairs report, September 3, 2026. New Bedford as reported by the New Bedford Light. Boston pilot figures from the City of Boston 2025 Surveillance Technology Report as reported by WBUR. G.L. c. 265, §§ 43 and 43A and c. 266, § 120F read at malegislature.gov and quoted from the statutory text. Mark Sherrick is presumed innocent. General information about Massachusetts law, not legal advice.