Lawsuit
Michael Williams jailed on ShotSpotter evidence
2021Michael Williams spent nearly a year in jail on ShotSpotter-based evidence before a judge tossed the case — fueling scrutiny of the technology's reliability in court.
ShotSpotter
Neighborhood microphones that claim to hear gunfire.
ShotSpotter blankets areas with acoustic sensors that detect suspected gunshots and dispatch police. Independent studies dispute its accuracy, and its placement concentrates in Black and Latino neighborhoods.
What it does
- ▸Acoustic sensor arrays
- ▸Gunshot triangulation
- ▸Real-time dispatch alerts
- ▸Forensic review
Where it's deployed
- ◍150+ US cities
- ◍Chicago non-renewal (2024)
Agencies using it
CPDNYPDLocal LE
Abuses & incidents
Investigation
89% of alerts, no gun crime found
2021A MacArthur Justice Center analysis found the vast majority of Chicago ShotSpotter alerts led to no evidence of a gun crime, driving claims it wastes resources and over-polices neighborhoods.
Ban / Halt
Chicago ends its contract
2024Facing accuracy disputes and community pressure, Chicago — one of ShotSpotter's largest deployments — declined to renew its contract.