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ShotSpotter: listening in on the neighborhood

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Re: ShotSpotter: listening in on the neighborhood

#371

Post by nonrandomstring »

hcfman wrote: post #268
nonrandomstring wrote: post #262

Earlier quoted context omitted.

Previously done a lot of research into firearm and explosive acoustics (and the DSP to locate and categorise) and can say this is a _hard_ problem. Military versions for use in wide open spaces have a much better chance than in urban areas. Less than five percent seems unlikely, but I wouldn't be surprised to hear "less than half the time".

Categorisation will certainly be error prone as there is so much similarity because fireworks and gunshots. The main difference I expect is the speed of the shockwave resulting in steeper spectrograms for gunshots. However, a steep spectrogram is essentially showing a large amount of high as well as low frequencies. The higher frequencies degrade very quickly over distance reducing the difference of a gunshot from a…

Nice work. PM me if you want to chat. Have you considered the possibilities with oversampling and adding more channels- now there are much cheaper 192kHz multi-chan ADCs on the market - these can be used with MEMS arrays. Then you can play with phase information much more freely.

Re: ShotSpotter: listening in on the neighborhood

#372

Post by lolinder »

Jun8 wrote: post #368
lolinder wrote: post #366

Earlier quoted context omitted.

> Just answer this question: your child had 10% chance of getting shot and killed walking to/fro from school, what would your position be on any technology that can reduce that by even 1%. Just to put some actual perspective on the numbers: about 40 kids are killed in all of New Mexico each year and about 20 of those are suicides (still tragic but not the walking-home-from-school kind). That's still too many, but is…

I’m talking about high crime areas in big cities. Here’s a data point from Chicago: in May 2021, up to that time in the year 108 children were shot, 16 of them died: https://abc7chicago.com/amp/chicago-shootings-child-shot-tee... It’s not the “heat of the crisis”, this has been going on for years now here. See this WaPo article from 2013, from when Michelle Obama attended the funeral of a 15 year-old girl: https://ww…

You're advocating creating policy based on emotion, not numbers. That is what I mean by creating policy in the heat of the crisis—the argument goes that it's better to do something than nothing, so we just throw surveillance at the wall and hope it reduces the number of tragedies.

I'm not advocating doing nothing, but I am advocating against arguments in favor of surveillance that lean heavily into emotions surrounding anecdotes and ignore questions of actual incidence rates, causality, and efficacy of the proposed solutions.

Re: ShotSpotter: listening in on the neighborhood

#373

Post by JKCalhoun »

throwaway9917 wrote: post #248
jcrawfordor wrote: post #71

Hello all, occasionally I write what I consider "Albuquerque content" and I do not expect it to become broadly popular. This article is something I put together very quickly and it probably assumes a certain degree of familiarity with the political context around policing in Albuquerque (which either side will tell you is very contentious) and, more broadly, policing and civil justice. Even without the currently evol…

The tone of your article makes me honestly, really angry. You know damn well that the reason the sensors are in those neighborhoods are because that's where people are getting shot. You even talk about how a school where some little kid got shot has a sensor, as if it's some sort of punishment for the lower income people there. Perhaps it's because the police and the city government want to deter or solve murders tha…

You might be interested in the documentary Divisible (2023)[1] that talks about redlining [2].

I caught it at the Omaha Film Festival and it has caused me to take a second look at the way our cities are organized in to "good" and "bad" parts.

[1] https://www.divisibledoc.com

[2] https://en.wikipedia.org/wiki/Redlining

Re: ShotSpotter: listening in on the neighborhood

#374

Post by assimpleaspossi »

humanistbot wrote: post #162
assimpleaspossi wrote: post #84

Earlier quoted context omitted.

It sounds like you are paranoid. Why would the government be listening to a conversation you might be having near a device used for tracking gunshots? Is there some little man somewhere just waiting to pounce on you or anyone just for that purpose? I don't know how effective these devices are but any tool that helps the police go after criminals is a good thing and no one should be fighting against good things.

Over a two year period in the US, there were over 600 cases where police officers and civilians with access to law enforcement databases violated internal policies and safeguards to access private data about "romantic partners, business associates, neighbors, journalists and others for reasons that have nothing to do with daily police work". This is certainly an undercount, as this is just who got caught and the depa…

The same thing may have occurred with an office just sitting in his squad car on a street corner. Will we now pull them off the streets for that reason? Will we require them to keep their windows rolled up or wear noise cancelling ear muffs?

The cases you cite are of people who did things wrong. The cases you cite have nothing to do with the advantages this gives to the police in protecting citizens and solving crimes.

Why do people keep fighting against the police who are trying to defend us against crimes? In general, these tools help and don't hurt anyone. Lest anyone forgets, the police are on our side.

Re: ShotSpotter: listening in on the neighborhood

#375

Post by whimsicalism »

smt88 wrote: post #174
whimsicalism wrote: post #142

Earlier quoted context omitted.

It works very well where I live (DC) and I and people I know have seen police respond to actual things with shotspotter Many shootings where nobody calls it in and cops respond with shotspotter

How would you know no one called it in? Also ShotSpotter has false positives. You have no way of knowing if you (or it) even heard a gun or one of many other things.

Here is one instance

https://en.m.wikipedia.org/wiki/Murder_of_Seth_Rich

We talked to the cops (not in this instance but in another homicide)

Re: ShotSpotter: listening in on the neighborhood

#376

Post by bnralt »

geraldwhen wrote: post #354
bnralt wrote: post #326

Earlier quoted context omitted.

Yeah, I always get the impression that the people talking about this really haven't spoken to the people in these neighborhoods. I've walked in neighborhoods here where the longtime residents came up to me and told me I should leave because it was dangerous (and I've spoken to others who have had a similar experience). It's always the people who grew up in suburbs and moved to the city as an adult who are dismissive…

In my area teachers are assigned somewhat randomly to schools. The goodness or badness of a school is 100% correlated with the kids, not the teachers. A single disruptive child can stop a class. When most of the class is disruptive, good luck teaching anything to anyone

Yeah, our government here spent years pouring money into low performing high schools to revitalize them, to little avail. Here's an interesting article on a very expensive (they spend $63,000 a year per student) boarding school they sent some kids to for free, that didn't have much of an impact[1].

Finally, what they did was they decided to split in half the high performing cohort from the best/wealthiest high school into two high schools. This cohort was now much smaller than the maximum capacity for either high school, which allows for a lot of out of boundary seats.

The problem is, even still they don't seem to be able to admit how important a high performing cohort is. If they did, there are plenty of things they could do to attract more of them to public schools and neighborhood high schools. For instance, there's at least one high school in the city that is very low performing, but has a large number of very high performing students in boundary. The parents want the school to guarantee some high level classes for their students, but it won't. They want the school to provide a safe environment, but the school can't commit to that (it's hard to remove students even if they are repeatedly violent). And if they do, they run the risk of national media reporters (who would never send their kids to these types of schools themselves) going after them[2].

[1] https://twitter.com/notcomplex_/status/1762607726817923545 [2] https://www.nytimes.com/2020/07/23/podcasts/nice-white-paren...

Re: ShotSpotter: listening in on the neighborhood

#377

Post by helpfulclippy »

jacurtis wrote: post #133
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.

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…

How would we know if this is true? For instance, is the source code subject to independent review, with verifiable builds made from that source so that all deployments have to show matching hashes? Or is more of a pinky-swear kind of a thing? If so, is the pinky swear even documented somewhere?

Re: ShotSpotter: listening in on the neighborhood

#378

Post by Spooky23 »

bko wrote: post #346
jncfhnb wrote: post #328

Earlier quoted context omitted.

Are you saying the quoted passage is a lie?

There's two explanations: 1. Cops use enforcement on poor neighborhoods because they like to make their lives difficult and because they hate poor people 2. Cops use enforcement there because that's where the crimes take place Explanation 2 is so obviously much more likely that I can't take the person that purports reason #1 without acknowledging the other explanation. They're playing dumb.

Or...

3. Cops use performative enforcement in poor neighborhoods because it yields metrics important to them with minimal effort.

Poor neighborhoods are often demanding and crying out for enforcement of laws. Nobody wants to live next to a crackhouse, and the people forced to lack options to leave. In my city, there's a notorious drug house that has been in operation since I was in college in the 1990s. It has better staying power than Walmart -- it's still there. What poor people in general resent to the point of riot about is systematic bullshit and abuse on the part of ineffective police.

When the powers that be say "clean up that area", they round up stupid kids for bullshit, maybe hit up a few street dealers, etc. The actual hard work, say arresting street gang leadership or investigating property crimes isn't sexy and takes time. The best documented examples are NYPD, where the worship of Excel sheets resulted in sweeps where the cops would issue appearance tickets for such offenses as "obstructing the public sidewalk" (ironically doing so, btw, when they are literally parking their personal vehicles on sidewalks for these big sweeps), than run through and make arrests for failure to appear a few months later.

Shotspotter in particular is stupid - it's just a way to blow Federal grant money. If as you say, the police "know where the crime is", why would they need microphones to tell them where gunshots go off? Presumable they patrol high risk areas and hear it themselves.

Police departments are paramilitary organizations. That means they need a military like level of accountability and discipline to function well, and the nature of modern governance is such that that is lacking. The Army doesn't tolerate drunken soliders runing amok, but police departments do. IMO the best way to address the issues of policing is to consolidate smaller departments into state or regional entities to both professionalize and reduce the chummy nature of what goes on.

Re: ShotSpotter: listening in on the neighborhood

#379

Post by throwaway323929 »

throwaway9917 wrote: post #248
jcrawfordor wrote: post #71

Hello all, occasionally I write what I consider "Albuquerque content" and I do not expect it to become broadly popular. This article is something I put together very quickly and it probably assumes a certain degree of familiarity with the political context around policing in Albuquerque (which either side will tell you is very contentious) and, more broadly, policing and civil justice. Even without the currently evol…

The tone of your article makes me honestly, really angry. You know damn well that the reason the sensors are in those neighborhoods are because that's where people are getting shot. You even talk about how a school where some little kid got shot has a sensor, as if it's some sort of punishment for the lower income people there. Perhaps it's because the police and the city government want to deter or solve murders tha…

This sounds a little far fetched, but my current hypothesis is that Americans have developed a co-dependent attachment disorder on a societal level around sociopaths that transcends ideology, whether they are certain presidential candidates or violent criminals. It's an enablement/abuse cycle that you typically see with alcoholic or abusive partners. Books on attachment theory have hinted that this type of disorder can occur on a macro level, which I was initially dismissive of, but when you apply it current events it really helps to explain a lot of irrational behaviors.

In the country with 21,000 homicides a year, it's hard to ignore the connection to attachment disorders while watching people wring their hands and make up exotic concerns that would be more fit for a Ray Bradbury novel over anything designed to address the world leading rates of violent gun crime, up to and including the literal concept of laws and the enforcement of those laws.

I don't know what the solution here is, because I don't know how you send an entire country to therapy and/or Al-Anon, but not continuously enabling the people that are hurting us is a great start, and that necessarily requires shifting empathy from the people that don't deserve it (violent criminals) to the people that do (their traumatized victims).

Apologies for the throwaway account but a lot of people get ridiculously emotional over this topic, and that's when I'm not accusing them of being societally co-dependent.

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