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Comment by theultdev | Hacker News Reader

That article is quite a mess isn't it? Seems they found more of a problem with the Chicago PD than ShotSpotter.

> If this result is attributable in part to missing or nonmatched records of investigatory stops that did take place as a direct consequence of a ShotSpotter alert, CPD’s record-keeping practices are obstructing a meaningful analysis of the effectiveness of the technology.

Should have been the end of the article right there, but techdirt decided to write one anyway.

And false positives really aren't that big a deal anyway. You get false police reports, at least with the sensors you can recalibrate and adjust.

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"The study, which reviewed ShotSpotter deployments for roughly 21 months (from July 1, 2019, through April 14, 2021) using data obtained from the City of Chicago, found that 89% of ShotSpotter’s reports led police to find no gun-related crime and 86% turned up no crime at all, amounting to about 40,000 dead-end ShotSpotter deployments."

If only we took companies out to defend their product at face value we could waste even more time and resources!

Yes and then they go to say there's missing data for them to attribute investigations to ShotSpotter due to CPD’s lack of record keeping.

So much so that it's "obstructing a meaningful analysis of the effectiveness of the technology". Their words, not mine.

That would undermine the original point you made, though:

> Everywhere it's installed officers find usefulness in triangulating where shots are popped off.

At best, cops are going on 'feels' here because, presumably, the data aren't sufficient to provide a solid basis for analysis. Or the police are withholding data that proves the system works well, which prima facie seems unlikely.

I've only heard anecdotes of cops saying it worked well, and it does seem like a good investment and an achievable goal.

I don't know what the real numbers are, but from that article it seems noone does...

A proper reporting of numbers would be nice.

You wouldn't want to waste officers time responding to those calls, but sending an automated surveillance camera is a different use of resources. Most surveillance cameras spend 99.99+% of their time watching no crime happening.

I would rather the cameras go to the gunshot noises than stay bolted to a pole outside my house, which is where they are now.

Those systems wouldn't be that automated, you'd need a whole fleet of techs and others to maintain them. And why to chase the 10% change the alert is anything at all. To me it sounds like the tech improvement needed in this situation is being applied in the wrong place.

Yes, and they have those systems (fixed cameras, shotspotter, and drones) now that they maintain. We're just talking about using them together.

Also, a faster response could result in a better rate of finding crime. "89% of ShotSpotter’s reports led police to find no gun-related crime" does not equal "89% of reports weren't gunshots". It could be that police show up too late.

> Yes, and they have those systems (fixed cameras, shotspotter, and drones) now that they maintain. We're just talking about using them together.

In a sort of magical way where there is a drone that can easily be dispatched from within it's range that has the intelligence to not only navigate to the scene through a complex city environment but also find and gather evidence. I bet any current drone deployment is likely to be slower than dispatching people patrolling and there will be far fewer of them than regular cops. It's basically fantasy when the Shot Spotter stuff doesn't even seem to work.

Statements like "shotspotter doesn't work" are reductive. Let's be specific about what it does and doesn't do. Some departments have found the data to not be actionable using current response methods. However, the systems are good at detecting gunshot like noises. This data is much more actionable for placing a camera than how cameras are placed today, which is "this intersection is near where crime happened last year, let's bolt a camera to the pole"

Drone navigation has been progressing quite a lot over the past decade, and law enforcement in some places is already using them in an automated way, as the article mentions. Also, the suggestion above was forward looking, it wasn't suggesting that the NYPD should glue these systems together today.

> Let's be specific about what it does and doesn't do

It doesn't tell a gunshot from a dumpster lid slamming shut.

It does produce almost entirely false positives.

It doesn't identify the location of a gunshot to any useful level of precision.

I suppose if you want to start a police state, and make every fourth resident a cop, you might be able to mitigate the 90% false-positive rate, and the horrible location-identification rate, but at that point, do you even need shot-spotter?

Those are exactly some of the things that augmenting the data with video would help to address, which was the point of the above suggestion.

Right now, police have data about where loud sounds generally come from, and video from fixed poles where crime happened in previous years. Both of these aren't great data points on their own.

The intersection of that data: [Video around locations where loud noises just happened] is probably much better than disjointed data points of [video of where crime happened in previous years] and [general locations of where loud sounds are happening].

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