Gunshot detection

On March 4, 2026 Chicago agreed to pay $500,000 to Michael Williams, who was charged with murder in 2020 after prosecutors used audio from ShotSpotter sensors as key evidence that he had shot a man inside his car. Williams spent nearly a year in jail before a judge dismissed the case at prosecutors’ request for insufficient evidence. His federal lawsuit, brought with the MacArthur Justice Center, alleged police misused the technology. The city’s Law Department said the payment resolved the case before trial and included no admission that the city was legally at fault. SoundThinking issued a statement the same day saying the company’s data had helped clear Williams.

In August 2025 the City of Chicago agreed to settle Williams v. City of Chicago, a class action brought on behalf of two men who were stopped and frisked after ShotSpotter alerts, in separate incidents on the South and Northwest sides. The city’s Law Department put the settlement at $90,000. As part of the agreement the city conceded that a ShotSpotter alert alone does not justify stopping or patting down a person who happens to be near the alert location. The city had stopped using the system in September 2024 and, at the time of the settlement, was considering bringing gunshot detection back.

On February 27, 2025, the Savannah City Council considered authorizing the city manager to rescind the award for a Real-Time Crime Center Public Safety Platform from Fusus Corporation and re-award to Axon Enterprise, Inc. in an amount not to exceed $150,000. The original award to Fusus was made on July 27, 2023. Fusus was bought by Axon. The platform would unify Savannah Police Department data and operations, provide real-time access to over 1,000 cameras, integrate ALPRs, Flock, and Shotspotter applications, and create a voluntary community camera registry. The purchase is sole source from Axon.

Baton Rouge Police Chief Thomas Morse Jr. is ending a $400,000 annual contract with gunshot detection company ShotSpotter, according to a Feb. 10, 2025 report. The police department is cutting nearly $9 million from its budget. The technology, in use since 2007, covered six of the city’s 80 square miles. In December, the system detected 42% of 470 reported gunshots, according to data from the district attorney’s office. Morse said he was not sure the technology was responsible for a single arrest since he became chief.

Chicago became the largest American city to drop ShotSpotter when its contract expired on September 23, 2024, after six years and roughly $49 million in spending. Mayor Brandon Johnson allowed the contract to lapse, following studies showing the system rarely produced evidence of gun crime, sent officers on tens of thousands of dead-end runs, and disproportionately surveilled Black and Latino neighborhoods. The city has not announced a replacement.

Chicago’s contract with SoundThinking for the ShotSpotter gunshot-detection network ended September 22, 2024, followed by a two-month transition period. The city entered a $33 million, three-year contract in 2018; WTTW reported the city paid more than $53 million since 2018. In February 2024 Mayor Brandon Johnson signed a nine-month extension reported by the Sun-Times at $8.6 million, more than the previous year’s cost. A 2021 Office of Inspector General review of 50,176 alerts from January 2020 to May 2021 found 9.1 percent produced evidence of a gun-related crime. The City Council voted 34-14 in May to require a council vote before removal from any ward, and later voted 33-14 to rebuke Johnson’s decision; the mayor vowed a veto.

On June 20, 2024, the New York City Comptroller’s office released an audit of NYPD’s ShotSpotter program. The audit found that in June 2023, officers responded to 940 alerts, of which 13% (122) were confirmed shootings. Fewer than 1 in 5 alerts result in a confirmed shooting. Since 2014, NYPD has spent over $45 million on ShotSpotter and committed an additional $9 million. In June 2023 alone, NYPD personnel spent almost 427 hours investigating unconfirmed alerts. The audit recommends declining to renew the contract when it expires in December 2024.

Chicago’s Office of Inspector General reported that ShotSpotter alerts rarely lead to confirmed gun-related evidence. Analysing the alerts from January through May, the office found that of 50,176 notifications, only 9.1% indicated evidence of a gun-related offense and only 2.1% linked directly to investigatory stops. The report said alerts can change officers’ behavior in patrolling areas. Deputy Inspector General Deborah Witzburg said there is little data linking alerts to recovered evidence or stops. The report came amid the city’s extended $33 million contract with ShotSpotter for two years.

Voice of San Diego obtained San Diego Police Department data covering 584 ShotSpotter activations from late 2016 through February 2020. SDPD classified 72 activations, 12.3 percent, as unfounded. ShotSpotter’s senior vice president of marketing Sam Klepper said the company had a 0.5 percent false-positive rate. Police made two arrests while responding to activations; nearly 60 percent of dispatches produced no report. SDPD Lt. Jeffrey Peterson wrote in December 2019, ‘I don’t support keeping it based on the cost.’ The city’s $1 million four-year contract was set to expire Nov. 21.