Brandon Johnson, the Mayor of Chicago, promised to end the city's contract with SoundThinking during his campaign. SoundThinking produces and distributes an acoustic gunshot detection system (AGDS) called "ShotSpotter."

More than four months after he took office as Mayor of Chicago, Johnson has yet to fulfill his campaign promise. We need you to write to his office to ensure that he stays true to his word and cancels the city's wasteful and harmful contract with SoundThinking.

Holding Mayor Johnson to his word is more important than ever as we expect the city budget to be announced next week. At one point, Johnson's firm and public commitment to ending the city's ShotSpotter contract was so strong that his comments resulted in the company's stock value plummeting. However, Johnson's office has already approved a $10 million extension of the contract into early 2024. The Mayor claims that this was done without his express approval.

The Chicago ShotSpotter contract started in 2018, and is now valued at nearly $49 million. During his campaign, Johnson said that ShotSpotter is too expensive and that there is “clear evidence it is unreliable and overly susceptible to human error.”  

If Johnson were to end its contract with SoundThinking, it would be the largest city to do so in the company’s 26 year history. In cities that have had ShotSpotter contracts and then canceled them, there is no clear overall trend in homicide reduction before or after implementation - this holds for Atlanta, GA, Canton, OH, Charlotte, NC, Dayton, OH, New Orleans, LA, San Antonio, TX, and Trenton, NJ. Chicago should follow suit. Below we explain why.

What is ShotSpotter?

ShotSpotter is an Acoustic Gunshot Detection System (AGDS) used by law enforcement to detect and report the location of gun fire. In the course of monitoring for gunshot-like sounds, ShotSpotter sensors continuously record audio, usually in high-minority neighborhoods. Without a warrant or any individualized probable cause, their sensors inevitably surveil many innocent people going about their daily activities.

ShotSpotter is used in more than 130 U.S. cities and towns.

ShotSpotter publicly boasts a 97% accuracy rate and 0.5% false positive incidence rate. Cities do not own the data they produce, and SoundThinking has yet to make this data publicly available for an independent audit, thus casting doubt on the technology’s supposed accuracy and efficacy.

The MacArthur Justice Institute calculated that there were 87 unfounded ShotSpotter Chicago PD deployments per day (31,640 in total) from April 2021 to April 2022. Restore The Fourth has run the calculations, and have determined that these false reports cost the city of Chicago $6,307.50 per day, or over $2.2 million a year in police wages alone.

The same MacArthur Justice Institute study reviewed 21 months of ShotSpotter deployments in Chicago and found that 89% found no gun-related crime and 86% reported no crime at all. The City of Chicago Office of Inspector General (OIG) conducted a similar study and found that CPD response to ShotSpotter alerts rarely produced documented evidence of a gun-related crime or recovery of a firearm.

ShotSpotter is predominantly deployed in Black and Brown communities. In Chicago, the 12 districts with ShotSpotter installations are those with the highest populations of Black and Latine residents.

ShotSpotter constitutes a faulty, ineffective mass surveillance network that is both invasive and dangerous.

It's time to tell Mayor Brandon Johnson to end the City of Chicago's contract with SoundThinking, and make a monumental step toward protecting his constituents privacy and civil liberties.