THE COMPANY THAT sells ShotSpotter, the acoustic gunshot detection technology that has come under attack recently from everyone from Boston city councilors to the state’s two US senators and Congresswoman Ayanna Pressley, is firing back. And it brought in the big guns to do so.

Holding forth in an interview last week at the Boston offices of Regan Communications, William Bratton, the celebrated former Boston police commissioner who went on to helm the police departments in New York City and Los Angeles, shot back at critics of the technology. Bratton, who sits on the board of SoundThinking, the California-based company that sells ShotSpotter services to police departments, accused elected officials who have questioned the technology of “political posturing” and said community residents, city leaders, and police officers who are closest to the problem strongly support the gunshot detection system. 

Bratton was slated to be joined in Boston by SoundThinking CEO Ralph Clark, but a flight cancellation forced him to join the conversation via Zoom from California. 

ShotSpotter, which is used in more than 170 US cities, relies on an array of sound detectors deployed across city neighborhoods to detect gunfire. With acoustic readings of a gunshot from multiple sensors, the technology can pinpoint the location of the shots and enable police to be deployed quickly to the scene, often even before a 911 call has been received, the company says. 

Boston has had the system in place since 2007, but as the ShotSpotter contract renewal approached this spring, critics said the city should do away with the technology. Some city councilors questioned its value, and a report released in April by the ACLU of Massachusetts charged that almost 70 percent of ShotSpotter alerts in Boston led to no evidence of gunfire. What’s more, the organization said, the alerts cause an “over-policing of communities of color, encouraging police to comb through neighborhoods and interrogate residents in response to what often turn out to be false alarms.”

In February, Chicago Mayor Brandon Johnson announced that he would follow through on a campaign promise to not renew the city’s ShotSpotter contract that expired that month (though he extended use of it until September). Several other US cities have also opted to end their use of the technology, and SoundThinking’s stock has taken a big hit, falling 43 percent since the start of the year. 

In May, Massachusetts Sens. Ed Markey and Elizabeth Warren, Rep. Ayanna Pressley, and Sen. Ron Wyden of Oregon sent a letter to the Department of Homeland Security inspector general asking him to investigate whether ShotSpotter – which many communities pay for using federal grant money – violates the 1964 Civil Rights Act because of its high rate of false alerts and its disproportionate deployment in Black and Latino neighborhoods.  

Bratton slammed the Massachusetts pols for “grandstanding” on an issue he said they don’t understand. “They jumped on the bandwagon,” he said. 

“They got finessed by the ACLU,” said Clark. 

Clark countered the claim of high false alarms by saying ShotSpotter data indicate there was gunfire in 97 percent of alerts. He said a failure to find ballistic evidence at a scene isn’t proof of no gunfire. The company says shootings from a vehicle, for example, would not leave shell casings. 

As for criticizing the concentration of ShotSpotter sensors in Black and Latino neighborhoods, Bratton says that attack defies common sense. “You put the device where the problem is,” he said. “How often do you hear gunshots up in Beacon Hill? How often do you hear it out here on Atlantic Avenue?” he said of Regan Communication’s waterfront offices.  

Northeastern University criminal justice professor Eric Piza has conducted one of the most comprehensive studies of ShotSpotter, looking at 15 years of data on its use in Kansas City and Chicago. He says police got ShotSpotter alerts, on average, about 90 seconds earlier than 911 calls, and the technology led to police locating more ballistic evidence at shooting scenes. But the research concluded that shootings were not more likely to be solved after the introduction of the technology to an area, and there was no evidence that ShotSpotter reduced gunshot fatalities through faster emergency medical response, as SoundThinking claims. 

Bratton said there are benefits of ShotSpotter beyond any direct impact on solving gun crimes or reducing gunshot fatalities. “What it does provide to the police is a huge trove of information about how significant the gun problem is in different neighborhoods in a city. That’s of critical importance to the police,” he said. Clark said studies suggest as much as 80 to 90 percent of gunshots go unreported in some communities. 

Bratton and Clark said the technology can play a vital role in helping police identify the extent of the gun violence problem in a community and any shifts in where it is occurring, information that can inform deployment plans and other strategies to stem the problem. 

While there has been some pushback against ShotSpotter in Boston, Police Commissioner Michael Cox has been a staunch defender of the technology as an important part of the department’s overall public safety strategy. Boston renewed its three-year contract with SoundThinking on July 1. The previous three-year contract was for $782,000. The police department did not respond to multiple requests asking for the amount of the new contract.  

“ShotSpotter is a useful tool to bring a quicker, more precise response from our officers to victims, a neighborhood and a crime scene,” the department said in a statement. “While technology is important, it is imperative to note that we spend a tremendous amount of time and resources in the areas where ShotSpotter is deployed focused on community policing and proactive efforts to support those we serve who may be vulnerable to crime. When people’s needs are supported, they and their community gets stronger, they are more a part of public safety and that is how we effect real long-term change.”