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GPS glitched across the US by as much as 33 feet

sciencealert.com

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Re: GPS glitched across the US by as much as 33 feet

#91
post #12

This is exactly the sort of thing that leads to people getting reincarcerated after their electronic monitoring devices mistakenly report them leaving their homes. Some reporting I did on the topic a few years back: https://chicagoreader.com/news/many-on-house-arrest-in-cook-...

I misread that as "people getting reincarnated" and was momentarily very confused.

Probably more beneficial than "people getting reincinerated" which is how I almost read it but thought that couldn't possibly be it.

Re: GPS glitched across the US by as much as 33 feet

#92
It seems worth mentioning that the last time GPS had issues like this afaik, it was due to the US utilizing 'selective availability' due to national security issues. We used it somewhat famously during the 9/11 attacks.

Also the page 404's via archive.org, but information formerly from gps.gov can still be found here: https://archive.ph/trwOo

Edit: The selective availability page moved to https://www.gps.gov/selective-availability

Re: GPS glitched across the US by as much as 33 feet

#93
post #88

Earlier quoted context omitted.

Geofence monitors have buffer zones because a small GPS on someone’s ankle inside a house, potentially a high rise, isn’t going to be that precise. 33 feet is well within the allowances IIRC. Varies by state.

According to this firm selling them, this model has At the very least, it's not enough evidence provided to claim the scenario is inherently impossible based on undefined "allowances" without any actual numbers for something completely dependent on the jurisdiction, monitoring software implementation, and attitude of the police officer/judge. https://www.youtube.com/shorts/o0sPXL9C53g I also found Reddit anecdotes of…

It happened with both RF and GPS! The Cook County Sheriff's Office moved between the two at one point so it was possible to see the effects over time as folk moved over. Some people got more false alarms when moving to GPS, some got fewer. IIRC it was about even.

Re: GPS glitched across the US by as much as 33 feet

#94
post #31

Earlier quoted context omitted.

That’s how all “estimated damages” work. It’s all just made up by some random person who guesstimated a number then multiplied it by the maximum possible people effected, realistic or not.

There’s probably a reasonable methodology but it has a lot of multiplications and some base parameters that make the whole thing wildly sensitive.

Yes, it's actually based on an economic model seemingly developed with a detailed understanding of modern farming practices and historical effects of timeline disruptions on yields. It may be approximate but isn't just some random dude guesstimating based on vibes or something.

https://farmdocdaily.illinois.edu/2024/05/how-will-the-gps-o...

https://shiny.agmanager.info/cottonBotsDev/

Re: GPS glitched across the US by as much as 33 feet

#95
post #84

Earlier quoted context omitted.

> non-violent, first-time offenders Non-violent, first-time offenders don't get ankle monitors. But thank you for highlighting my point.

They absolutely can, depending on the jurisdiction. I saw plenty of cases out of Atlanta with drug possession cases with no prior history getting an ankle monitor, back when they were live streaming bond hearings from Rice street.

[flagged]

Re: GPS glitched across the US by as much as 33 feet

#96
post #48

Earlier quoted context omitted.

> This As in, GPS being off by 33 feet? > leads to people getting reincarcerated I'm reading your article and it seems to be about police coming to check and realizing that the reporting of being miles away was in error, not people getting reincarcerted because of GPS incorrectly reporting they moved ~30 feet too far? One of these is much more insane than the other.

The story is about GPS errors which end up making life hell for people under monitoring since they end up generating a Police response. If 80% alerts were false, then an error like this can result in a surge of these alerts. It is an important story to tell.

The monitoring device story seems important to tell but the problem seems to be related to monitoring devices, which are supposed to be accurate to 30 meters 90% of the time, being miles off or even reporting the wrong state. That kind of systematic failure does not make a few meters of displacement any more relevant. Saying so really makes it sound like the problem is something significantly less egregious than the devices being incomprehensibly inaccurate - as if we have to solve space weather prediction to a new level of science to not have them report someone in Chicagoland as being in Delaware.

Re: GPS glitched across the US by as much as 33 feet

#97
post #69

Earlier quoted context omitted.

> To answer your question Looking forward! > motions by prosecutors Motion ≠ incarceration. So, not an answer (yet?)... Did defendants get incarcerated as a result of these motions, or no?

They did, yes. I hope you have a better day.

Okay thanks, so here's what I don't understand. When there is video evidence that someone was in their house the whole time, and given that everyone who has used a GPS knows it can easily be inaccurate by 30ft, why in the world would the judge trust the ankle monitor accuracy over video footage they see with their own eyes that directly contradicts it?

Something about this just doesn't seem very plausible, especially if this kind of thing is happening more than once in a blue moon. Either the video evidence is not as convincing as we're being led to assume (thus leaving more doubt in the judge's mind than ours, even if the person is innocent), or there should be some other explanation.

Re: GPS glitched across the US by as much as 33 feet

#98
post #58

Earlier quoted context omitted.

"You've essentially claimed police/judges are doing something rather stupid and terrible." Yes, yes I am. You really need to realize just how unbelievably fucking arbitrary the criminal courts are. At every level. They're not tech people. To answer your question, I have examples of motions by prosecutors to suspend people from the EM program where they specifically cite specific data points just barely out of their h…

> To answer your question Looking forward! > motions by prosecutors Motion ≠ incarceration. So, not an answer (yet?)... Did defendants get incarcerated as a result of these motions, or no?

You've kind of spoiled my day with this. Its like an angry chess game when you've got momentum, you POUNCE! But nobody else here appears to have chosen violence. really I get that he "maybe snarked you". But you should be reminded of the beautiful rules of hn discussions.

Re: GPS glitched across the US by as much as 33 feet

#100
post #41

Earlier quoted context omitted.

If someone's home is 30' by 30' feet, yes, that person's device will report them having left their home and they'll get a visit if GPS suddenly shifts 30 feet to the left. I'm talking about the class of problem. It happens in normal weather conditions and things like this exacerbate the problem. Really not sure what the hostility's about.

GPS is not that accurate even on a good day. A small device attached to someone’s ankle with a small antenna and an obstructed view of the sky will frequently be registering locations outside of the footprint of someone’s house. A single 33 foot anomaly is already within the geofence buffer zones used. In dense urban areas the geofence buffer allowance may be 10X that already.

It should be treated that way but we’re talking about elected prosecutors who are itching for an excuse to put people in prison rather than looking “soft on crime” by allowing people to live under house arrest.
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