Michael Williams gunshot detection wrongful arrest

A Chicago retiree was wongly arrested and jailed for nearly a year after Chicago Police Department (CPD) officers accused him of shooting and killing a neighbour sitting next door to him in his car on the basis of an 'unreliable' ShotSpotter gunshot detection alert.

Prosecutors cited ShotSpotter sensors to bolster 63-year-old Michael Williams' case. But, according to a motion (pdf) filed by Williams' attorney, the company’s algorithms had initially classified the sound as a firework and the location co-ordinates had been altered. 

The admission persuaded the prosecutors to withdraw ShotSpotter evidence against Williams and the judge to dismiss the charges.

The incident raised questions about the accuracy and reliability of ShotSpotter, and prompted concerns about the extent to which SoundThinking may have been altering data to suit its customers.  

In July 2022, the MacArthur Justice Center filed a class-action lawsuit (pdf) on behalf of Williams and two other claimants for mental anguish, loss of income, and legal bills. The suit also sought a court order barring the technology’s use in Chicago.

System

• ShotSpotter gunfire detection

• SoundThinking/ShotSpotter responds to false claims

• SoundThinking (2022). VICE Media retracts allegations that ShotSpotter altered evidence

Legal, regulatory

• Illinois v Michael Williams (pdf)

• Illinois vs Michael Williams - Amicus Brief (pdf)

• Illinois v Michael Williams - Frye Motion (pdf)

• MacArthur Justice Center (2022). Williams v City of Chicago

Investigations, assessments, audits

• AP (2023). Confidential document reveals key human role in gunshot tech

• AP (2022). Lawsuit: Chicago police misused ShotSpotter in murder case

• AP (2022). How AI-powered tech landed man in jail with scant evidence

• AP (2021). Police Are Telling ShotSpotter to Alter Evidence From Gunshot-Detecting AI

• Chicago Office of the Investigator General (2021). OIG finds that ShotSpotter alerts rarely lead to evidence of a gun-related crime and that presence of the technology changes police behavior

News, commentary, analysis

• https://www.cbsnews.com/chicago/news/chicago-man-says-flaws-with-shotspotter-technology-had-him-framed-for-murder-files-lawsuit/

• https://apnews.com/article/artificial-intelligence-algorithm-technology-police-crime-7e3345485aa668c97606d4b54f9b6220

• https://apnews.com/article/gun-violence-technology-crime-chicago-lawsuits-3e6145f63c96593866cf89ac01ce7498

• https://www.chicagoappleseed.org/2022/08/24/lawsuit-cpd-faulty-evidence-from-shotspotter/

• https://blockclubchicago.org/2021/08/23/activists-want-city-to-cut-ties-with-shotspotter-but-chicago-police-already-extended-its-contract-two-more-years/

• https://www.datasciencecentral.com/shotspotter-ai-at-its-worst/

• https://futurism.com/the-byte/man-sues-chicago-ai-wrongly-imprisoned