"Shot Spotter"? Not Really

Spend a lot of money, get algorithms.  And we know about algorithms, no?  One Chicago resident spent a year in jail awaiting trial for a "shooting" that did not happen.

...Williams’ experience highlights the real-world impacts of society’s growing reliance on algorithms to help make consequential decisions about many aspects of public life. Nowhere is this more apparent than in law enforcement, which has turned to technology companies like gunshot detection firm ShotSpotter to battle crime. ShotSpotter evidence has increasingly been admitted in court cases around the country, now totaling some 200. ShotSpotter’s website says it’s “a leader in precision policing technology solutions” that helps stop gun violence by using “sensors, algorithms and artificial intelligence” to classify 14 million sounds in its proprietary database as gunshots or something else.

But an Associated Press investigation, based on a review of thousands of internal documents, emails, presentations and confidential contracts, along with interviews with dozens of public defenders in communities where ShotSpotter has been deployed, has identified a number of serious flaws in using ShotSpotter as evidentiary support for prosecutors.

AP’s investigation found the system can miss live gunfire right under its microphones, or misclassify the sounds of fireworks or cars backfiring as gunshots. Forensic reports prepared by ShotSpotter’s employees have been used in court to improperly claim that a defendant shot at police, or provide questionable counts of the number of shots allegedly fired by defendants. Judges in a number of cases have thrown out the evidence.

ShotSpotter’s proprietary algorithms are the company’s primary selling point, and it frequently touts the technology in marketing materials as virtually foolproof. But the company guards how its closed system works as a trade secret, a black box largely inscrutable to the public, jurors and police oversight boards...

There's more at the link.  Suffice it to say that "Shot Spotter" is about as reliable as "eye-witness" accounts.

Not very much at all.