This week, the New York City comptroller released a similar report audit from the city’s ShotSpotter system showing that only 13 percent of the alerts the system generated over an eight-month period could be confirmed as shots fired. Auditors noted that while the NYPD has the information necessary to release data on ShotSpotter’s accuracy, it does not do so. They described the department’s accountability measures as “inadequate” and “insufficient to demonstrate the effectiveness of the tool.”
Champaign and Chicago have since canceled their contracts with Flock Safety and SoundThinking, respectively.
“Raven has over 90 percent accuracy in detecting gunshots and about the same percentage accuracy in detecting fireworks,” Josh Thomas, senior vice president of policy and communications at Flock Safety, tells WIRED in a statement. . “And, most importantly, Raven alerts officers to incidents of gun violence that they would never have known about. In the San Jose report, for example, of the 111 truly positive gunshot alerts, the SJPD states that only 6 percent were called to 911.”
Eric Piza, a professor of criminology at Northeastern University, has conducted some of the most comprehensive studies available on gunshot detection systems. in a recent study of In shooting incidents in Chicago and Kansas City, Missouri, his team’s analysis showed that police responded faster to shooting incidents, stopped their vehicles closer to the scene of shootings, and collected more ballistics evidence when responding to alerts. gunshot sensors compared to calls to 911. However, there was no reduction in gun-related crimes and police were no more likely to solve gun crimes in areas with gunshot sensors than in areas without they. That study only examined confirmed shootings; did not include false positive incidents in which systems incorrectly identified gunshots.
In another study In Kansas City, Piza found that reports of shots fired in areas with shot sensors were 15 percent more likely to be classified as unfounded compared to reports of shots fired in areas without systems, where police would have relied on calls to 911 and other reports. methods.
“If you look at the different objectives of the system, research shows that (gunshot detection technology) typically tends to result in faster police response times,” Piza says. “But research has consistently shown that gun violence victimization does not reduce after gunshot detection technology is introduced.”
The New York City comptroller recommended that the NYPD not renew its current $22 million contract with SoundThinking without first conducting a more thorough performance evaluation. In its response to the audit, the NYPD wrote that “non-renewal of ShotSpotter services may endanger the public.”
In its report, the San Jose Digital Privacy Office recommended that the police department continue to look for ways to improve accuracy if it intends to continue using the Raven system.
Pointing to the report’s finding that only 6 percent of confirmed gunshots detected by the system were reported to police through 911 calls or other means, police spokesperson Sergeant Jorge Garibay told WIRED that the SJPD will continue to use the technology. “The system continues to be useful in providing supplemental evidence for a variety of violent firearms crimes,” he says. “The hope is to solve more crimes and increase apprehension efforts, which would desirably lead to a reduction in gun violence.”
