Quincy’s 49 Flock cameras captured 689,000 license plates in the last 30 days. Police searched 76 of them. Police Chief Mark Kennedy offered those numbers to the City Council on Tuesday, October 6, 2026, as proof that the system is used narrowly. Dozens of residents heard the same numbers and drew the opposite conclusion: that the city is photographing everyone to find a few.
Both readings come straight out of the one Supreme Judicial Court decision on license plate readers. Here is what happened in Quincy, and what that decision says about exactly this question.
What happened Tuesday night
According to WHDH and WCVB:
- A City Council oversight committee heard from dozens of residents, most urging a ban. They raised data sharing, privacy, misuse and accountability. “These cameras passively track the movement of every vehicle and person that passes, not just vehicles tied to active criminal investigations,” one resident said.
- Chief Kennedy said 48 officers are approved to use the system and the department adopted a misuse policy in January. He said the city cut its retention period from 30 days to 14, that none of the data was shared with other police agencies in early August, and that Flock does not have access to RMV records: “the detective has to take the next step and run that plate.” He said the system has helped solve crimes including two homicides, kidnappings and sexual assaults.
- Norfolk District Attorney Michael Morrissey urged the council not to “get rid of one of the more valuable tools to solve violent crimes,” and said Flock helped track down the Brown University shooter last year.
- Gideon Epstein of the ACLU criticized “contract language that gave Flock the company, and not its customers in law enforcement, the ability to control their own data.”
No vote was reported. WCVB counted at least 18 Massachusetts municipalities that have stopped using Flock; our running list of towns that dropped Flock cameras is here.
689,000 versus 76: why both sides cite the same numbers
The chief’s point is that 76 searches is a tiny fraction, and each one started with a specific investigation. The residents’ point is that 689,000 plates were recorded either way, and the protection against misuse is a policy, not a law.
The SJC addressed this tension directly in Commonwealth v. McCarthy, SJC-12750, decided April 16, 2020. Police had used four license plate reader cameras on the Bourne and Sagamore bridges to track a suspect’s trips onto and off Cape Cod. The court held that four cameras at two fixed locations did not amount to a search. But it went further, in a passage that every Massachusetts council debating Flock is effectively arguing about:
“With enough cameras in enough locations, the historic location data from an ALPR system in Massachusetts would invade a reasonable expectation of privacy and would constitute a search for constitutional purposes.”
The court described this as an aggregation principle, sometimes called the mosaic theory: collected over enough time and enough places, “the cumulative nature of the information collected implicates a privacy interest.” It also said a one-year retention period “certainly is long enough to warrant constitutional protection.”
That framework explains why Quincy’s specific numbers matter legally:
- Number of cameras. McCarthy turned on four cameras at two choke points. Quincy has 49 in one city. We are not aware of any Massachusetts appellate decision saying how many cameras in one city cross the line.
- Retention. Fourteen days is far shorter than the one year the SJC flagged. Shorter retention makes a constitutional challenge harder.
- Sharing. A network that pools data with other departments looks more like the statewide system the court worried about. Kennedy’s statement about data sharing in August is aimed at that concern.
- Search controls. If accessing historic data is a search, police would need a warrant to query it. A misuse policy is not a warrant requirement, and that is where residents’ accountability arguments land.
What state law says: almost nothing yet
Massachusetts has no statute specifically regulating license plate readers. That is why each city and town is deciding for itself, and why the policies Kennedy described exist only as department rules. Boston 25 has reported lawmakers pushing new rules, but none has become law. Our explainer on Flock cameras and Massachusetts law has more.
The misuse cases are real. WCVB noted that officers in Braintree, New Bedford and Lynn have faced discipline for misusing the technology.
Frequently asked questions
How many Flock cameras does Quincy have?
49, according to Police Chief Mark Kennedy, who said they captured 689,000 license plates and police searched 76 in the last 30 days.
Is it legal for police to use license plate readers in Massachusetts?
Yes, there is no state law banning them. The SJC held in Commonwealth v. McCarthy (2020) that four cameras on two bridges were not a search, but said that with enough cameras in enough locations, historic ALPR data would be a search requiring constitutional protection.
How long does Quincy keep Flock data?
14 days, reduced from 30, according to the police chief.
Has Quincy banned Flock?
No vote was reported after the October 6 committee hearing.
Sources: WHDH and WCVB, October 6-7, 2026. Commonwealth v. McCarthy, SJC-12750 (April 16, 2020), read on CourtListener. General information about Massachusetts law, not legal advice.