CAMBRIDGE — Cambridge's City Council voted 5-2 Tuesday to yank the plug on the gunshot-detection system that's been alerting the city's cops to gunfire since 2014 — eight days after a paroled cop-shooter unloaded at least 60 rounds at Memorial Drive traffic and left two innocent drivers fighting for their lives.
Mayor Sumbul Siddiqui voted with the majority. The directive gives the city manager 90 days to rip the ShotSpotter sensors off Cambridge rooftops.
What got killed
ShotSpotter — now branded SoundThinking — is a network of rooftop microphones that catch the sound of gunfire, route the audio through algorithms and human reviewers, and ping local cops with a location within seconds. Cambridge has run it since 2014.
Activists hate it. The technology's accuracy is contested — the MacArthur Justice Center's 2021 Chicago analysis found that 89 percent of ShotSpotter alerts there produced no cop-confirmed gunfire. ShotSpotter's defenders fire back: "not confirmed" is not the same as "no gunfire." Shell casings get cleaned up. Witnesses don't talk. And every dispatched alert lets officers verify that a quiet block is actually quiet.
Cambridge's own ShotSpotter performance data? Nowhere in Tuesday's public vote. The woke councilors killed the system without putting a single Cambridge-specific accuracy number on the public record.
The council's stated reasons
Councilors cited four reasons for ripping out the system:
MASSDAILYNEWS
STAY UPDATED
Get Mass Daily News delivered to your inbox
ADVERTISEMENT · Interested in advertising?
ADVERTISEMENT · Interested in advertising?
- Privacy — fears of acoustic surveillance of Cambridge neighborhoods
- False positives — the broader-cities accuracy debate
- Over-policing — claims of disparate impact on specific neighborhoods
- Federal data-sharing — fears that ShotSpotter alerts could land in the hands of U.S. Immigration and Customs Enforcement
That fourth one is new.
Cambridge appears to be the first major U.S. city in the country to publicly cite ICE-data-sharing fears as a reason for killing gunshot detection. Chicago dropped ShotSpotter in 2024. Atlanta dropped it in 2024. Durham dropped it in 2023. None of them mentioned ICE. Only Cambridge — at the height of Massachusetts's sanctuary-state push — made shielding illegal immigrants from federal data-sharing a public reason for shutting down gunfire alerts.
Public testimony in support of the order included this gem from the chamber: "BIPOC members of the Cambridge community are more likely to be recorded by ShotSpotter."
Critics responded — accurately — that ShotSpotter sensors are microphones. They do not see skin color. They record sound.
Whether ShotSpotter's deployment pattern across Cambridge neighborhoods has a disparate-impact problem is a different, defensible policy question. The "microphones can't see race" objection answers a question the speaker didn't actually ask. Both can be true. Neither helps Cambridge cops respond to gunfire faster.
ADVERTISEMENT · Interested in advertising?
ADVERTISEMENT · Interested in advertising?
The eight-day gap
The vote came eight days after the May 11 Memorial Drive shooting — when Aaron Brown, a paroled felon already convicted of shooting a police officer, walked into broad daylight on Memorial Drive and sprayed at least 60 rounds at oncoming traffic. Two innocent drivers caught his bullets and went to the hospital fighting for their lives. A state trooper and a private citizen with a Massachusetts License to Carry put Brown down before he could empty another magazine.
Aaron Brown, the paroled felon accused of unloading at least 60 rounds at Memorial Drive traffic on May 11, 2026, in surveillance and bystander footage of the incident.
— End Wokeness (@EndWokeness) May 19, 2026🚨Cambridge Mayor Sumbul Siddiqui votes to disable gunshot detection technology to help migrants
That's the exact kind of incident — public, broad daylight, no cops on scene at the moment of fire — that ShotSpotter exists to flag in real time. Eight days later, Cambridge's woke City Council voted to rip the system out. MDN's prior coverage of the Memorial Drive shooting and Councilor Mike Connolly's defense of the gunman is here.
What happens next
In 90 days, Cambridge cops will only learn about a shooting if someone calls 911. In areas where residents don't dial in fast — where, say, the gunshots come from a passing car — Cambridge's response time just got worse by design.
Loading Comments