ShotSpotter Gunshot Detection System Expands to Major U.S. Cities

ShotSpotter’s acoustic gunshot detection system undergoes major expansion across the United States during 2015, with significant deployments in New York City and Sacramento representing the technology’s growing adoption by major metropolitan police departments.

In August 2015, the New York City Police Department expands ShotSpotter to three additional coverage areas for a total of eight coverage areas citywide. The NYPD will enter a second agreement in 2016 to dramatically expand the system to 20 coverage areas covering approximately 60 square miles of the city. This represents one of the largest ShotSpotter deployments in the country and signals major police departments’ increasing reliance on automated acoustic surveillance technology.

Sacramento obtains ShotSpotter in 2015, establishing another significant West Coast deployment. The Sacramento Police Department will renew the contract for five years in 2020, demonstrating long-term commitment to the technology despite emerging questions about its effectiveness and cost.

ShotSpotter’s technology uses networks of acoustic sensors deployed across neighborhoods to detect and locate the sound of gunfire. When sensors register sounds that may be gunshots, the audio is analyzed by a combination of automated algorithms and human analysts at ShotSpotter’s headquarters. Alerts are then sent to police departments with the location and time of the detected gunfire, typically within 60 seconds of the incident.

The company claims the technology helps police respond more quickly to shootings, particularly in cases where residents may not call 911, and assists with evidence collection and crime scene investigation. During this expansion period, ShotSpotter lists 93 cities as clients, including major metropolitan areas like Chicago and New York.

However, the technology’s expansion occurs without adequate scrutiny of its accuracy or effectiveness. The company markets a claimed 97% accuracy rate, but this figure will later be revealed as misleading—it represents only the percentage of alerts that police departments voluntarily report as errors, not an independent verification of the system’s actual performance.

The acoustic surveillance raises privacy concerns as well. The sensors are capable of recording conversations and other ambient sounds in addition to gunfire, creating the potential for mass surveillance of neighborhoods where the systems are deployed. ShotSpotter’s placement disproportionately targets predominantly Black and Latino communities, contributing to over-policing and increased law enforcement presence in already heavily surveilled areas.

The technology will face growing scrutiny in subsequent years as studies reveal extremely high false positive rates, with some analyses finding that more than 90% of ShotSpotter alerts do not lead police to evidence of gun-related crime. Questions will also emerge about the modification of ShotSpotter evidence and its reliability in criminal prosecutions.