After years of legal back-and-forth, Cambridge City Council voted Monday to approve a $400,000 settlement with retired Cambridge Police Department lieutenant Thomas Ahern, closing out a long-running legal fight over a 2019 on-duty weapon discharge. The vote was split, with Mayor Sumbul Siddiqui and Councillor Jivan Sobrinho-Wheeler opposed and Councillor Ayah Al-Zubi absent. The agreement resolves a federal lawsuit Ahern filed claiming he was retaliated against after raising safety concerns about the department-issued Sig Sauer P320 pistol.
The council signed off on the payout following a tense debate over whether to settle or roll the dice at trial. As reported by Cambridge Day, six councillors — Patty Nolan, E. Denise Simmons, Cathie Zusy, Marc McGovern, Tim Flaherty and Vice Mayor Burhan Azeem — voted in favor.
What happened in the SWAT van
On May 19, 2019, Ahern’s department-issued P320 discharged while he was in a parked SWAT van at the Harvard Square Mayfair event, with the bullet hitting his cellphone and lodging in a ballistic helmet. No one else was injured. Those details appear in a December 16, 2024 U.S. District Court memorandum, as laid out in GovInfo. Ahern told investigators he had removed the gun from its holster to inspect why it would not reseat, and that the pistol went off while he was holding it.
Officer raised concerns, then sued
Ahern says he began raising concerns about the P320 as early as 2017 and later sued both Sig Sauer and the city, alleging product defects and retaliation. As reported by WCVB in 2021, his lawsuit claims the pistol fired without a trigger pull and that he faced negative personnel actions after speaking up. Ahern retired on January 5, 2023 after nearly three decades with the department, by which point disciplinary measures had not been finalized, according to court filings.
Why the case survived dismissal
In a December 16, 2024 decision, U.S. District Court Judge Denise J. Casper rejected the city’s bid for summary judgment, ruling that a jury must decide whether Ahern’s speech about gun safety played a role in personnel decisions. The ruling allowed his First Amendment and Massachusetts Whistleblower Act claims to move forward. The memorandum details the judge’s legal analysis and the disputed evidence, as set out in GovInfo.
City swapped out the P320s last year
In 2025, citing supply and safety concerns, the city moved to replace the P320s, buying Walther handguns and holsters that automatically activate officers’ body cameras, according to reporting from last August. As Cambridge Day noted, officials said the P320 "Carry" model used by the department was no longer available and that parts were hard to get. City leaders told councillors the switch was not driven by litigation, while critics argued the timing only deepened public skepticism.
Council split over transparency and liability
Councillors grappled with a familiar dilemma: whether paying out would shut down public scrutiny or simply protect taxpayers from a potentially bigger hit at trial. Skeptics warned that repeated settlements can soften pressure to reform police practices, while supporters cast the deal as basic risk management. During the meeting, some councillors pointed to past large payouts by the city — including a $1.4 million settlement reported by the Boston Globe — as context for their votes. The split outcome highlighted ongoing friction between demands for transparency and fears of mounting legal liability in police-related cases.
What the settlement means
The settlement ends Ahern’s federal claims and wraps up the court battle between him, the city and Sig Sauer, but it leaves unanswered whether his complaints about the P320 counted as protected speech in the eyes of a jury. The case had already pushed broader questions into the spotlight about how the city buys equipment and how internal safety concerns are handled. City officials did not go beyond the formal council action, and public reporting indicates attorneys for the parties did not immediately offer additional statements.
The vote closes out this particular dispute for Ahern and City Hall, while leaving policy debates over procurement and oversight very much alive. Advocates pressing for more transparency and tighter vetting of police equipment are likely to keep the pressure on councillors in the months ahead.
