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ShotSpotter: listening in on the neighborhood

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Re: ShotSpotter: listening in on the neighborhood

#231

Post by duped »

dmoy wrote: post #171
jcrawfordor wrote: post #125

Earlier quoted context omitted.

Let me follow up, and maybe I should write this up on CAB but I don't really want to get too much into police reform there, what I know factually about the ShotSpotter system. Most of this comes from discussions with APD leadership and officers in the context of the police oversight role I used to hold, and they are very much limited in what they can say. Some of this is specific to APD SOP and other police departmen…

> less than five percent of cases Wow that's even worse than what I had read from reports about the deployment in Chicago (which I read up on when Seattle was considering it). I think the value was like 10%. Chicago also ditched it recently I think.

Here's a decent article because this happened in recent weeks (1). The numbers they cite there are 89% of alerts lead to no reports of gun crime and 86% lead to no crime reports at all.

All that being said, the metrics are horribly flawed because they assume police will actually investigate anything after dispatch and that the investigation will turn anything up. Believing that CPD is going to case a neighborhood looking for GSR and shell casings with a forensics team is a tall order. If there isn't someone bleeding out in the street there probably isn't going to be a police report filed.

And even that said - ShotSpotter is useless because it requires police to do their job to be useful. When Reddit is better at tracking gang violence than cops, no fancy audio forensics tool is going to help.

(1) https://www.npr.org/2024/02/15/1231394334/shotspotter-gunfir...

Re: ShotSpotter: listening in on the neighborhood

#232

Post by wahnfrieden »

bhaney wrote: post #144
jacurtis wrote: post #133

Earlier quoted context omitted.

Yes it is very important. Shotspotter is like a DVR. It's always "recording", but it is running on a very very short recording loop. The detection of gunshots is based on an algorithm. When triggered, it saves a few seconds before the sound and several seconds afterward. It is different than police just being able to pull up the recordings for a certain street corner from 2 weeks ago or even a day ago and listen in o…

> it is running on a very very short recording loop I'm curious what your source for that information is

They made it up

Re: ShotSpotter: listening in on the neighborhood

#233

Post by seanmcdirmid »

ryandrake wrote: post #211
jakelazaroff wrote: post #208

Earlier quoted context omitted.

Yeah, that’s the original point I made which is currently being downvoted.

I think there's a lot of quiet classism going on in this thread, and it's easier for these guys to just drive by and hit the downvote button than to actually speak their mind and tell us why they think poor people -> criminals. The causation more likely goes the other way: When an area gets the reputation of being higher crime (because of reality or because of bias from more police saturation), that area becomes chea…

> The causation more likely goes the other way: When an area gets the reputation of being higher crime (because of reality or because of bias from more police saturation), that area becomes cheaper to live in, and poorer people can then afford to live there.

Isn’t that called de-gentrification, or maybe ghetto-ization? However, I think it’s the opposite with property crime (richer neighborhoods attract property crime because their is lots of property to steal).

Re: ShotSpotter: listening in on the neighborhood

#234

Post by reaperman »

wl wrote: post #139
reaperman wrote: post #119

Earlier quoted context omitted.

ShotSpotter has (used to?) manually changed the location of detected gunfire to placate police who needed the evidence to point to their primary suspect. Then they could go to court and say “this system showed the gunshots came from the suspect’s location”. But “the system” didn't show that, until ShotSpotter employees manually changed the data. They spent a lot of effort hiding that as well.

They don’t change the data. They change their interpretation of it. The police say the classifier got something wrong, so the classification gets updated, both for the record and to improve the classifier. The police say that the location is wrong. The company looks at the data, maybe finds that the system automatically located on an echo at one or more sensor and then recomputes the location using the primary pulse.

The “data” which gets presented in court is the classification. So they changed the “data”.

The underlying algorithm wasnt subject to examination by defense teams until a rules change like, last week.

Re: ShotSpotter: listening in on the neighborhood

#235

Post by jjallen »

Retric wrote: post #165
verteu wrote: post #116

Earlier quoted context omitted.

Why didn't you mention that the only "conversation" recorded by ShotSpotter admitted in court was a guy saying "[shooter's name], why did you shoot me!" two seconds after the sound of gunfire? It seems an important piece of context if you are concerned about surveillance.

There are multiple conversations from shot spotter admitted into court. New Bedford, Connecticut and Oakland had court cases off the top of my head, but a much wider range of conversation ends up being listened to by police and parallel construction is a thing. Further, the concern is unequal policing biases statistics resulting in more uneven policing. A grid of microphones covering a full city is unbiased, placemen…

Isn’t this whole article about shooting though and not drug crime? How would you hear drug crime?

Are shooting crimes known to be fairly evenly distributed across different incomes?

Re: ShotSpotter: listening in on the neighborhood

#236

Post by sbierwagen »

demondemidi wrote: post #104
grugagag wrote: post #91

Earlier quoted context omitted.

Are people shooting blanks?

I've never actually seen "blanks" at any sporting goods or gun store in the 15 years I was really into guns. Reloaders typically reload rifle bullets, so I find it highly unlikely anyone is shooting blanks. Especially during drunken sportsing celebrations.

If you're buying ammo online and sorting by cost per round, it's easy to make an expensive mistake: https://twitter.com/westernunion2k/status/141712299595750604...

Re: ShotSpotter: listening in on the neighborhood

#238

Post by pillusmany »

scheme271 wrote: post #219
Aurornis wrote: post #197

Earlier quoted context omitted.

> The more you monitor an area, the more samples you get, biasing the stats So by monitoring an area with high crime rate, you catch more crime, which results in more policing for the area with a confirmed high crime rate? And that's a bad thing?

It's biasing the sample. For example, drug usage among teens are roughly the same between white, hispanic and african americans but african americans are more likely to be arrested and charged for drug possession or usage. Here the difference is probably because african americans are stopped and searched more even though their usage is about the same as whites.

Are the rates of drug dealing the same through?

Re: ShotSpotter: listening in on the neighborhood

#239

Post by bilbo0s »

sbierwagen wrote: post #224
incanus77 wrote: post #54

Timely, as a boy was shot at last week in Chicago while setting off fireworks that triggered a ShotSpotter alert: https://chicago.suntimes.com/crime/2024/02/27/chicago-police...

He was setting off fireworks on January 25? Is there a holiday on that day I'm not aware of?

You're stretching man.

We're a nation of laws, not of your awareness. It's just the words on the page. Was there a law being broken or not. In this case the answer was no. The police then proceeded to write up multiple claims of illegal activity that were all demonstrable falsehoods, and your defense of the illegal activity on the part of the police is that you aren't aware of a holiday?

This is just the sort of thing we need to stamp out before these thugs kill either some other innocent kid, or cause a real police officer to be hurt or killed while trying to control the inevitable community reaction to their bird brained behavior.

These cops need to be off the force yesterday. Yes they are liabilities waiting to happen. Yes they are dishonest. But the real reason we need to get rid of them is because they are unpredictable. We have no idea what anyone who will shoot at innocent kids and lie about it today will do tomorrow.

Honest cops are predictable. Dishonest cops are just loose cannons and we need to cut them out at every opportunity.

Re: ShotSpotter: listening in on the neighborhood

#240

Post by jakelazaroff »

pillusmany wrote: post #238
scheme271 wrote: post #219

Earlier quoted context omitted.

It's biasing the sample. For example, drug usage among teens are roughly the same between white, hispanic and african americans but african americans are more likely to be arrested and charged for drug possession or usage. Here the difference is probably because african americans are stopped and searched more even though their usage is about the same as whites.

Are the rates of drug dealing the same through?

Let me put it this way. The biggest drug epidemic of this century was the opioid crisis. Half a million Americans died. The primary people responsible are white billionaires, and we know exactly who they are — yet they were never even arrested.
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