Best of the Week


AP investigation finds gunshot detection technology has helped send innocent people to jail

Michael Williams sits for an interview in his South Side Chicago home, July 27, 2021, after spending nearly a year in jail as a suspect in a May 2020 killing. Prosecutors had used ShotsSpotter evidence to build their case against Williams. “I kept trying to figure out, how can they get away with using the technology like that against me?” he asked. “That’s not fair.” His case was eventually dismissed when prosecutors said they had insufficient evidence. (AP Photo / Charles Rex Arbogast)


For months, investigative reporters Garance Burke, Martha Mendoza and Juliet Linderman had been digging into a controversial tech tool favored by police, an algorithm-powered gunshot detection system they learned was being used as evidence in criminal trials that helped send innocent people to prison.

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Michael Williams sits for a portrait in his South Side Chicago home, July 27, 2021. Williams sat behind bars for nearly a year before a judge dismissed the murder case against him. – AP Photo / Charles Rex Arbogast

The trio contacted dozens of defense attorneys nationwide, pored over thousands of documents, including confidential material from the California-based company ShotSpotter, and built relationships with sensitive sources, including Michael Williams, a 65-year-old grandfather who had just spent nearly a year in a Chicago jail. Williams’ attorneys contacted Burke exclusively to let her know that he was about to be released after prosecutors dropped their murder charge against him. The reason? The ShotSpotter evidence prosecutors used to build their case was “insufficient.”

That break became the basis for the first investigation in a new series called “Tracked,” funded by the Pulitzer Center on Crisis Reporting. Burke and Linderman hurried to Chicago for the first of a series of interviews with Williams at his Chicago home, which put a human face to a story about inanimate algorithms that can change the course of people’s lives.

Legal affairs reporter Michael Tarm joined the effort, obtaining records through the Freedom of Information Act and sources, and securing an interview with the family of the man Williams was accused of killing. With footage shot by Chicago video journalist Teresa Crawford and photos by Charlie Arbogast, producer Serghino Roosblad edited a moving minidocumentary about Williams’ life and struggles following his release.

The resulting story was picked up by hundreds of outlets,including the major Chicago papers. Even amid news from Afghanistan and the Capitol bomb threat,this was among the most-read stories on AP News,netting more than 158,000 pageviews.

Sen. Ron Wyden,R-Ore.,asked the Justice Department to look into whether ShotSpotter and other technologies contribute to bias in policing. The Chicago Sun-Times published an op-ed demanding that ShotSpotter evidence not be used in court. The AP team was interviewed about their findings,including by CBS News and WVON News,an influential Chicago talk radio station focused on the African American community.

For dogged document research,delicate source work,nimble reporting and all-formats collaboration,the team of Burke,Mendoza,Linderman,Tarm, Crawford and Arbogast and Roosblad is first runner-up for AP’s Best of the Week award.

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