Comment by YLE118 | Hacker News Reader

Comment by YLE118 | Hacker News Reader

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An egregious example from the first link:

Police said ShotSpotter, a surveillance system that uses hidden microphone sensors to detect the sound and location of gunshots, generated an alert for that time and place.

Except that’s not entirely true, according to recent court filings.

That night, 19 ShotSpotter sensors detected a percussive sound at 11:46 p.m. and determined the location to be 5700 South Lake Shore Drive—a mile away from the site where prosecutors say Williams committed the murder, according to a motion filed by Williams’ public defender. The company’s algorithms initially classified the sound as a firework. ...

But after the 11:46 p.m. alert came in, a ShotSpotter analyst manually overrode the algorithms and “reclassified” the sound as a gunshot. Then, months later and after “post-processing,” another ShotSpotter analyst changed the alert’s coordinates to a location on South Stony Island Drive near where Williams’ car was seen on camera.

And another:

In 2016, Rochester, New York, police looking for a suspicious vehicle stopped the wrong car and shot the passenger, Silvon Simmons, in the back three times. They charged him with firing first at officers.

The only evidence against Simmons came from ShotSpotter. Initially, the company’s sensors didn’t detect any gunshots, and the algorithms ruled that the sounds came from helicopter rotors. After Rochester police contacted ShotSpotter, an analyst ruled that there had been four gunshots—the number of times police fired at Simmons, missing once.

Paul Greene, ShotSpotter’s expert witness and an employee of the company, testified at Simmons’ trial that “subsequently he was asked by the Rochester Police Department to essentially search and see if there were more shots fired than ShotSpotter picked up,” according to a civil lawsuit Simmons has filed against the city and the company. Greene found a fifth shot, despite there being no physical evidence at the scene that Simmons had fired. Rochester police had also refused his multiple requests for them to test his hands and clothing for gunshot residue.

Curiously, the ShotSpotter audio files that were the only evidence of the phantom fifth shot have disappeared.

Both the company and the Rochester Police Department “lost, deleted and/or destroyed the spool and/or other information containing sounds pertaining to the officer-involved shooting,” according to Simmons’ civil suit

What I don't understand about this is what basis they could possibly have for making such a correction? The data is X, their algorithm says Y about it. Are they just claiming that "analysts" are better at triangulating than whatever their algorithm is? It's not like image classification, where it's at least plausible that a person can meaningfully "correct mistakes."

Their profit depends on pleasing the police departments that make these requests. They probably thought nobody would ever find out or care, which is why they sued to keep journalists quiet.

The microphones are not hidden you can see them, they are just discreet.

Kind of like speeding and red light cameras, though they could be placing small enough microphones that you wouldn't see them while driving/walking by.

Of course that seems like a small nitpick given the content of the passage I copied from the article.

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