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.

66-year-old Michael Williams was accused of shooting 25-year-old Safarian Harring while giving the young man a ride home from a police brutality protest on the basis that video surveillance footage showed Williams’ car stopped at the time and location where police said they knew Herring was shot due to a ShotSpotter alert.

Williams was subsequently sentenced to 38 years in prison, though, in 2021, a motion (pdf) filed by his attorney argued that 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 experience had a profound impact on Williams, who spent two years in prison for a crime he did not commit. He has spoken publicly about the trauma and stress he experienced during his incarceration and has advocated for greater transparency and accountability in the use of gunshot detection technology in law enforcement.

Williams' case raised concerns about the accuracy and reliability of ShotSpotter and the extent to which SoundThinking may have been altering data to suit its customers. It also highlighted the potential for wrongful convictions and the need for greater scrutiny of forensic evidence in court proceedings.

In addition, it underscored the importance of ensuring that law enforcement agencies and prosecutors are transparent about the limitations of technologies like ShotSpotter, and that they take steps to mitigate these risks in order to prevent miscarriages of justice.