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Audio Surveillance, Intended to Detect Gunshots, Can Pick Up Much More
New submitter groovethefish writes "This NYT article highlights the use of electronic listening devices installed on utility poles, buildings, and other structures, then centrally monitored for gunshots. The company SureSpotter claims it helps reduce time wasted by police searching for the source of gunfire in their patrol areas, but the privacy implications are just hitting the courts. If they are monitoring 24/7 and also pickup conversations along with gunshots, can that be used against the people who are recorded?" Evidently, Yes: the linked article describes just such a case. Continues groovethefish: "The company line, from the article: 'James G. Beldock, a vice president at ShotSpotter, said that the system was not intended to record anything except gunshots and that cases like New Bedford's were extremely rare. "There are people who perceive that these sensors are triggered by conversations, but that is just patently not true," he said. "They don't turn on unless they hear a gunshot."'"
QUOTE: "In at least one city, New Bedford, Mass., where sensors recorded a loud street argument that accompanied a fatal shooting last December, the system has raised questions about privacy and the reach of police surveillance, even in the service of reducing gun violence."
The Supreme Court has ruled people have no expectation of privacy in a public setting or publicly-open facility (like a mall). Note that also includes cops who try to make you turn-off your videocamera or audio recorder. They don't have any right to privacy either, and can not force you to turn them off, or confiscate & erase the evidence.
My AC stalker: " I personally agree with your posts most of the time, but that won't keep me from modding you troll"
"They don't turn on unless they hear a gunshot."
So, how are they listening for a gunshot, and then recording the gunshot, after the gunshot was fired?! Is that not a blatant lie or am I being daft?
I think they mean the recording portion doesn't turn on unless the sensing portion detects a gunshot. A poorly worded sentence, to be sure. It's like your TV - even when your TV is "off", the small component that listens for your remote is still on.
How can you verify a sound was a gunshot THEN record it?
In my state of Wisconsin, it is against the law to record a conversation between two parties without the express knowledge of one of the parties. This instance would most likely be inadmissible in any court case. I believe this is the recording law in many states as well, but I only have experience dealing with it here.
If the only way you can accept an assertion is by faith, then you are conceding that it can't be taken on its own merits
They don't have any right to privacy either, and can not force you to turn them off, or confiscate & erase the evidence.
They may not have any right to privacy but they certainly can, in real life, force you to turn them off, confiscate and erase the evidence. Doesn't mean it is legal for them to do so but they certainly are capable of doing it and probably will get away with it too. After all, once the evidence is deleted it becomes your word against theirs and they tend to hold the advantage there. Obviously cops should be held at least to the same standards as regular citizens (if not higher standard) but we know that it doesn't always work out the way it should in actual practice. The certainly aren't going to get thrown in jail and probably not even reprimanded and they know it.
The TSA scanners didn't store images until we found out they stored images. Then we were told they only stored images for testing until we found out they stored images all the time. Then we found out the images were easily accessible to anyone after being reassured that there were ample security measures to prevent any yahoo from distributing humiliating or enticing images of some people.
I swear to God...I swear to God! That is NOT how you treat your human!
Given a choice between outlawing guns and having a sensitive listening device on every street corner that can listen in on conversations like Big Brother, I'd prefer to outlaw guns.
While I agree it's not supposed to be permanent, a short circular buffer *is* a recording, and it means the device is on all the time.
For instance, the circular buffer used by the ReplayTV DVR for live TV pausing is supposed to be transient and inaccessible, but (due to a bug) it is possible to stream that video to other devices on the network. IIRC, the Tivo lets you save the pause buffer.
His statement shows that James G. Beldock is either ignorant of his company's own technology or attempting to "dumb down" the description of the technology to avoid scaring the common folk. Either way, it says nothing good about him or ShotSpotter.
TFA talks about an argument recorded by this system, associated with a shooting.
Unless the argument happened AFTER the shooting, it's unlikely they only start recording as a result of a shooting.
And it the argument DID happen after the shooting, I really can't see how it is even relevant to the case, unless the argument was on the order of "I can't believe you just shot that guy!! WTF?"
Which I don't believe, since I expect that if two people were wandering down the street, one pulled out a gun and shot someone else, then that two of them would be too busy running like hell to have an argument....
"I do not agree with what you say, but I will defend to the death your right to say it"
I implemented several IP cameras for a previous employer. They had a nifty little "record on motion" feature in which it wouldn't record (could still be monitored live) to the NAS unless there was motion detected. One of the big selling points around this feature was that it could actually record up to 30 seconds BEFORE the motion that triggered it so you could be sure you weren't missing anything before the camera was triggered. I believe it did it by keeping a couple minutes of video in a buffer on the camera. If an event triggered it, that buffer would be written to the NAS first and then it would continue appending the live video to the storage until the motion stopped plus X minutes. This system likely works in a similar fashion - it keeps a buffer that's continually overwritten until an event (IE: gunshot) triggers it to be saved to permanent media.
When I was there in 2005, some humvees had these. They didn't work well, and picked up a lot of false positives. When I returned a second time in 2006 / 2007, I don't recall seeing a single ShotSpotter. But the ShotSpotters made the guardshack's day when they could come back from dropping Marines at post and say "We were shot at! The ShotSpotter beeped, said it came from the right!"
I posted in more detail elsewhere in this article, but I installed a security camera system that could store some footage from before motion tripped the camera. Basically, once motion was in the frame (or a specific part of the frame), it writes everything from the buffer preceding the motion detection to storage and then appends the live video until X seconds/minutes after the motion stops. Unless there's a trigger, the preceding footage never gets written to storage. Technically, the buffer is a type of storage but it's very small, often overwritten, and only used if a trigger event is detected shortly thereafter.
You can do something where you continuously record and then throw away the recording after a few seconds if nothing was triggered. A lot of busses do that with video recordings so that they can have footage of a crash if it occurs.
DNA -- National Dyslexic Association
The military system is called Boomerang. It uses a cluster of microphones on a pole on a vehicle. The onboard systems can triangulate the shot directly, using the timing differences in the arrival of the gunshot.
When our name is on the back of your car, we're behind you all the way!
We should probably put a more critical eye towards possibilities.
The system turns on when it detects gunshots. But it's extra sensitive, so it often catches things that aren't actually gunshots. And it stays on for half an hour. Effectively, it's recording half the day.
Nominal behavior is not actual behavior.