View a previous report from Columbus police’s expansion of ShotSpotter in the video player above.

COLUMBUS, Ohio (WCMH) — Leaked documents claim to reveal the location of gunfire detectors in multiple major U.S. cities, as at least one of them has announced it will sever ties with the company behind the technology.

Wired magazine obtained leaked documents recently from ShotSpotter, now rebranded to SoundThinking, that showed around 25,500 microphones were placed throughout the country. Zooming in on the map shows just how many of those sensors are in Columbus. The documents claim the company focused its tech in the Hilltop and Linden neighborhoods, as well as the east side of the city. It also shows the locations of detectors in Mansfield, Dayton, Cleveland and Cincinnati.

However, the map doesn’t show any sensors in the Wedgewood neighborhood. Columbus police expanded its net of detectors to that area in May 2023, meaning the leaked data may have been compiled before then.

Comparing the locations of sensors against homicide data from the past two years from police does show similarities. The scattering of locations where the city’s most violent crimes took place doesn’t fit the Shotspotter detectors like a glove, but many of the city’s reported killings fall in their zones of focus. Still, the 2023 homicide data shows the places where crimes happened well after the city began its contract with the company and placed sensors in 2019.

A SoundThinking spokesperson could not comment on the data revealing the ShotSpotters to NBC4, as the company was “pursuing civil and criminal remedies” against the ex-employees that leaked it. However, as the maps above suggest, they said the sensors’ placements were based on “historical gunfire and homicide data.”

“Despite the claims that ShotSpotter alerts lead to bias and over-policing in predominately Black and Brown communities, ShotSpotter provides intelligence that allows police to coordinate safe, efficient, and equitable responses that require fewer resources in a way that builds community trust,” the spokesperson wrote. “When gunfire occurs, is it not preferable to ensure law enforcement and first responders know about it and can respond quickly to render aid to victims and secure the area?”

Columbus police rigorously tested their ShotSpotter sensors in late 2023. Over a two-day stretch, officers fired guns of multiple different calibers to judge the system’s sensitivity for picking up shots. However, the Columbus Division of Police didn’t respond to a request to share their findings, or any other data related to the system’s efficacy in the city. The Columbus Inspector General’s Office told NBC4 it hadn’t conducted any study on ShotSpotter, because it falls outside the agency’s jurisdiction.

That’s not the case in Chicago, where in February the mayor announced he would end the city’s ShotSpotter contract. The local inspector general’s office previously released a study it said showed the system wasn’t actually helping Chicago police find evidence of gun crimes, and altered officers’ behavior.

A SoundThinking spokesperson gave a data sheet to NBC4 with its specific claims about the sensors’ effect in Columbus. Inside, city police credited ShotSpotter alerts with helping them find and save three gunshot victims, because no one had called and reported the incidents. A national study didn’t dispute SoundThinking’s claims that ShotSpotter reduced officer response and victim transport times, and helped more accurately find crime scenes. However, it ultimately disagreed that this resulted in any meaningful difference in solving crime.

“We examined the effect of ShotSpotter with a pooled, cross-sectional time-series analysis within the 68 large metropolitan counties in the USA from 1999 to 2016,” researchers wrote. “Results suggest that implementing ShotSpotter technology has no significant impact on firearm-related homicides or arrest outcomes. Policy solutions may represent a more cost-effective measure to reduce urban firearm violence.”

In Ohio, Dayton police defended the ShotSpotter system as being helpful, but in the same breath decided to stop using it in December 2022.

“Due to the amount of work invested in the ShotSpotter area to reduce violent crime, it is
challenging to develop statistics showing how effective ShotSpotter would be on its own,” a spokesperson for the Dayton Police Department wrote. “While the ShotSpotter area shows a more considerable decrease in violent crimes, this cannot be solely attributed to ShotSpotter’s effectiveness, as it was only one of the many tools used to combat violent crime in this area during this timeframe.”

Dayton police claimed it would have cost around $615,000 over three years to renew their contract for a three-square-mile spread of sensors. Specifically, they blamed the state’s constitutional carry of firearms as part of why its cost couldn’t be justified any longer.

“Individuals are no longer required to have a permit to carry a concealed weapon in a vehicle unless they have a previous disqualifying crime. These are the primary ways we confiscate weapons and have weapon laws arrests,” the spokesperson wrote. “Additionally, firing a gun
within city limits is not illegal unless certain conditions exist.”

As of Monday and even given the changes in gun laws Dayton police cited, the City of Columbus had not given any hint that it had any intention to discontinue its relationship with SoundThinking.