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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

#81

Post by entrope »

IndySun wrote: post #23
hylaride wrote: post #20

Earlier quoted context omitted.

My understanding is that the encrypted military-level GPS is much more robust against jamming and spoofing. There's probably a lot of capabilities we don't know that's classified, too.

Called M-Code. Has a fascinating history. https://odimpact.org/case-united-states-opening-gps-data-for...

M-Code is a new encrypted signal that is not fully operational yet. OCX was supposed to enable it.

GPS has always had the P(Y) code, which is an encrypted signal, at a higher chip rate than the C/A code that has been broadcast on L1 forever. The P(Y) code has its own interesting history of (semi-)codeless processing. If the US military is lucky, the history books will close on that by 2030: https://www.gps.gov/codelesssemi-codeless-gps-access-commitm... . (Currently, 21 GPS satellites broadcast L5.)

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

#82

Post by Dylan16807 »

chaps wrote: post #58
dataflow wrote: post #47

Earlier quoted context omitted.

Do you have any examples of someone getting thrown behind bars due to a GPS error on the order of ~30ft like you're claiming? That's all I'm asking. Really don't understand why you keep avoiding it. You've essentially claimed police/judges are doing something rather stupid and terrible. I'm asking you to show example(s) of what you claimed (~30ft error → thrown behind bars), not something significantly different (~1+…

"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…

> Btw, the courts are public and you should try some criminal courts watching. Pick a random day and just go.

So you could find an example easily but you don't want to? Or you're suggesting court watching in general and not to find an example?

"I have an example I won't share" is better than nothing, I guess. But you were being snarky before you even said that much, when you were just linking your article and not saying if examples existed at all.

I'm curious why they're not yours to share, though. Did someone give them to you under private circumstances, or can people get there from public information but you think you shouldn't spread the word?

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

#83

Post by qlte »

avazhi wrote: post #54
boomboomsubban wrote: post #46

Earlier quoted context omitted.

The trackers are part of CCSO’s pretrial house arrest program, so presumably a number of them are attached to people who did no crimes.

> so presumably a number of them are attached to people who did no crimes. You and I have very divergent views of the type of person likely to be charged or prosecuted for a crime or indeed to participate in a diversion program that involves GPS trackers, my friend.

Your heuristic is flawed. The pool of defendants with pending charges who were granted pre-trial home detention are going to be disproportionately non-violent, first-time offenders compared to those denied bail or with prohibitively large amounts.

Meaning an error like this harms innocent people wrongly accused more than the stereotypically hardened repeat offenders you imagine to be undeserving of your sympathy and presumed guilty.

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

#84

Post by avazhi »

qlte wrote: post #83
avazhi wrote: post #54

Earlier quoted context omitted.

> so presumably a number of them are attached to people who did no crimes. You and I have very divergent views of the type of person likely to be charged or prosecuted for a crime or indeed to participate in a diversion program that involves GPS trackers, my friend.

Your heuristic is flawed. The pool of defendants with pending charges who were granted pre-trial home detention are going to be disproportionately non-violent, first-time offenders compared to those denied bail or with prohibitively large amounts. Meaning an error like this harms innocent people wrongly accused more than the stereotypically hardened repeat offenders you imagine to be undeserving of your sympathy and…

> non-violent, first-time offenders

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

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

#86

Post by chaps »

Dylan16807 wrote: post #82
chaps wrote: 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…

> Btw, the courts are public and you should try some criminal courts watching. Pick a random day and just go. So you could find an example easily but you don't want to? Or you're suggesting court watching in general and not to find an example? "I have an example I won't share" is better than nothing, I guess. But you were being snarky before you even said that much, when you were just linking your article and not say…

It wasn't easy to find, heh. Lots of FOIA requests to even get to a point of where I could go through court records at the Clerk of Courts. Obstinate lawyers for months and months. But after all that, I can find the court documents at the Clerk of Courts. I printed them there and I don't have them anymore. I would need to redact even if I had them. But they were all the same form, but with the actual violations largely hand-written notes written by a prosecutor in a hurry. It was usually a list of like, ten instances that they seemingly picked from random of the GPS rlogs. The best glance I had into what was by FOIA'ing the GPS records of someone who died much later but had a lawyer who fought tooth and nail to show he didn't leave his home. GPS is truly all over the place in these logs. I validate a lot of that against call center records that themselves took months to get but show when alarms and calls are made to the devices, plus when dispatch is done.

A lot of this stuff is hard to talk about because it's about real people in real pending (at the time) cases.. and I'm also not a criminal defense attorney by any means. There's a reason the first article I posted had their identity completely removed. There's weird liability and believe me I want to say more.

Very honestly, I wish I could have done more reporting on how fucked up those devices were. I put a lot of time and effort into reporting that couldn't make it to print, largely because I was doing freelance work at the time. The first offer I got for that piece was $50. Wasn't sustainable.

Do you have any questions about these EM programs?

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

#87

Post by userbinator »

chaps wrote: 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.

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

#88

Post by qlte »

Aurornis wrote: post #68
chaps wrote: 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-...

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 getting alert texts stepping outside onto the street from their yard, or false alarms while still inside but not enough details were provided to be sure they were actually GPS and not RF so not as helpful.

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

#89

Post by blululu »

bigfudge wrote: post #29
ck2 wrote: post #11

Earlier quoted context omitted.

yup that was my first link but of course this administration is never going allow China-anything like low cost electric cars even if it means saving people a fortune in gas so hopefully in 2029 it can be looked at again or maybe Dems will also get the Senate too and can be petitioned if they run out of corruption investigations before 2029 it is critical to explain to everyone who isn't technical that GPS is "read on…

Read only or not, relying on Chinese or Russian gps data for increased accuracy even in civilian increases dependency no? That seems like a bad idea to me. I’ve thought for about 20 years that increasing our dependence on anti democratic regimes was a risk, no matter what the benefits for global development etc. It’s not isolationist to want to only rely on your friends and not enemies. (Which is why Europe needs to…

If you are relying on it without a graceful fall back then it would be a problem. If you take it as a boost on top of existing capabilities then it is a pure win. In practice it can be hard to parse the two scenarios. People get used to thinking that something is available and it turns out that it was always leverage against them.

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

#90

Post by openasocket »

avazhi wrote: post #84
qlte wrote: post #83

Earlier quoted context omitted.

Your heuristic is flawed. The pool of defendants with pending charges who were granted pre-trial home detention are going to be disproportionately non-violent, first-time offenders compared to those denied bail or with prohibitively large amounts. Meaning an error like this harms innocent people wrongly accused more than the stereotypically hardened repeat offenders you imagine to be undeserving of your sympathy and…

> 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.
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