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United States, couple years ago my friend in his mid-thirties was feeling depressed after his mom died. Came over to hang out, and wasn’t responding to his sist
by donatj 3y ago
United States, couple years ago my friend in his mid-thirties was feeling depressed after his mom died. Came over to hang out, and wasn’t responding to his sisters calls.
His sister called in a welfare check on him and suddenly I have three cops knocking at my front door. They ask for him by name, say he isn’t in trouble. I go get him; he asks “how did you know where I was?” and the cops say “we pinged your phone”. What that entails exactly I have no clue.
Later I pulled up the video of them arriving on my cameras, they didn’t approach any of my neighbors houses first. It was just right to my front door like they knew exactly where he was. Kinda spooky.
- paxys 3y agoDespite all the technology in the world the majority of police work is still plain old-fashioned knocking on doors and making phone calls. People will always voluntarily give up all the information in the world to be seen as good citizens. In your friend's case I'm willing to bet that they asked the sister for the names of his close friends and acquaintances and yours matched up.
- neoromantique 3y agoor they just triangulated using his cell phone, it can be very accurate in urban settings
- internetter 3y agoSeems like much more work. Based on the stories I've seen about these operations to track down phones over the years, it's a little more complicated
- paxys 3y agoPolice need a warrant to get location data from your cell phone provider. No department is bothering with that for a welfare check unless the situation is really dire, and the process still takes a while to carry out. "Where do you think your brother is?" "Oh probably at XYZ's place" is a much more straightforward and common process.
- fsckboy 3y ago> Police need a warrant if the information they gather is to be admissible in court as evidence against a person. Police do not need a warrant to save the life of a person.
- neoromantique 3y agoI don't know the processes in US, but in Europe I saw this in action first hand done in minutes, so I don't know. edit: Over a stolen phone, no less, not even a person being in danger.
- paxys 3y agoIn the US the process is you go to the police to report a stolen phone and they say "tough luck, hope you had insurance".
- AmericanChopper 3y agoI have some family who are dispatchers (not in the US), and they have the ability to immediately get location data directly from providers if they think somebody is in imminent danger. They can’t do it to track a suspect (not without a warrant), but they would regularly do it for suspected suicides, or when a caller communicated they were in danger but failed to give their location for what ever reason. I wouldn’t be surprised if many jurisdictions around the world had similar systems.
- soared 3y agoThat’s for the person who is actively calling 911 though, not a random persons phone.
- AmericanChopper 3y agoIn the cases I’m familiar with it was often used for other people calling in suspected suicide attempts (or other types of self harm, or drug overdoses, ect…)
- Kirby64 3y agoSeems much more likely that his sister knew the friend, and suggested he might be there? Or there was some relation to the friend to know the exact address. Unless he lived at a single-family house, it's unlikely a phone's GPS would be exact enough.
- orangepurple 3y agoYou experienced a type 0 SMS. It can wake the GPS on a modern phone and return a GPS location. Last time I checked cell tower triangulation is accurate to between a few hundred and a few thousand feet. Cellular A-GPS can be good to within a few feet inside houses usually but often its within a few tens of feet in accuracy.
- mcpackieh 3y ago> Last time I checked cell tower triangulation is accurate to between a few hundred and a few thousand feet That was about what LTE could do. With 4G, they got it down to 20-50 meters. Now they can do much better.
- kevin_thibedeau 3y agoNo. They can locate anyone's phone on demand. The services that do this can generate a likely street address from GPS or tower triangulated location. This is how many criminals now get caught while on the run. It isn't magic police work but rather the personal tracking device everyone carries. Likewise some spree killers have been tracked down by geofencing phones known to be around all crime scenes and zeroing in on the one that shows up at all/most of them.
- soared 3y agoSource?
- xethos 3y agohttps://en.wikipedia.org/wiki/Sensorvault https://en.wikipedia.org/wiki/Sensorvault is for Google, with the 3 linked sources being very fun reads.
- kevin_thibedeau 3y agohttps://www.oxygen.com/crime-news/cell-phone-data-from-lori-vallows-brother-alex-cox-helped-authorities-find-kids-remains https://www.oxygen.com/crime-news/cell-phone-data-from-lori-...
- deleted 3y ago[deleted]
- hollerith 3y agoYour "on demand" makes it read like they don't need to get a warrant whereas your link describes a missing-children investigation that had already made the national news, i.e., a situation in which getting a warrant would be very easy.
- kevin_thibedeau 3y agoI've had it used on me personally without a warrant. There are no deep controls on this tech. You just have to know someone who can do a favor.
- npteljes 3y agoI like this idea, very human. Social engineering basically. And at the end, they are not required to tell you their method.
- InCityDreams 3y agoBut they can't find a stolen bicycle with a gps tracker as the gps information 'may not be accurate'. Similar for phones. /(am in europe)
- npteljes 3y agoThat's just it, they are doing their own thing. This is why I liked the explanation, it reflects that the police is not an organization that's somehow representing and enforcing a higher moral standard, but rather a distinct thing that has its own life and culture. And that social engineering and parallel construction are part of daily life.
- thallium205 3y agoThey just call the phone and the system will typically triangulate it if it rings. It's used all the time in search and rescue.
- tivert 3y ago> Despite all the technology in the world the majority of police work is still plain old-fashioned knocking on doors and making phone calls. People will always voluntarily give up all the information in the world to be seen as good citizens. In your friend's case I'm willing to bet that they asked the sister for the names of his close friends and acquaintances and yours matched up. Sure, but that doesn't pass the smell test in this situation: 1. That's a lot of work, which would take a lot of time to do. For instance, does the sister know the OP's number. His full name? His first name? Are they going do all the work to piece together fragmentary information for a wellness check? 2. The technology exists and is widely deployed for the police to straightforwardly take a quick shortcut around all that work. And most importantly: 3. The police said they took that shortcut.
- ubermonkey 3y agoTriangulation by cell tower is really, really accurate.
- nine_k 3y agoDoesn't such tracking require a warrant? Looking at call logs may require less.
- mrguyorama 3y agoCops can freely buy anything from one of Peter Thiel's panopticon products. He can buy all the data from brokers and companies for a pretty high price, and sell it to cops for an equally stupid price, and your tax dollars get used to bypass the entire concept of a warrant.
- hackmiester 3y agoNo, no need for a warrant. If the cops ask nicely (as opposed to making a demand), and the provider provides the info, there was no need for a warrant. That is the common process today.
- hocuspocus 3y agoNot really, best in class network probes will regularly give you positions that are wrong by a few km, you need quite a bit of cleaning to reconstruct accurate paths. That's why something like MDT was added to 3GPP standards and emergency calls trigger a hard GPS fix.
- hackmiester 3y agoSure, that seems like something that could happen. However, meanwhile, in practice, my friend was having a mental break and the cops narrowed my friend's location down to 3 possible houses in a neighborhood.
- hocuspocus 3y agoSee this comment: https://news.ycombinator.com/item?id=36617330 https://news.ycombinator.com/item?id=36617330 Abusing emergency location services is a much better explanation here. They can ping the device for a short time and it'll do its best (using A-GPS and WiFi) to provide an accurate position, without involving anyone since it's fully automated. Collecting positions from a carrier's network infrastructure is a more complex and slow task in comparison.
- squarefoot 3y agoThe police can access all call logs; if they found your number among his last calls, starting from your house would have been among the first things to do in normal investigation.
- JohnFen 3y ago> the cops say “we pinged your phone”. What that entails exactly I have no clue. The cell phone infrastructure knows where your phone is. It has to in order for it to operate. The police routinely ask cell phone companies for locations of cell phones. Many (most?) not only won't require a warrant, but provide an official portal the police can use to conduct their queries without having to get a phone company employee to do it.
- ChuckNorris89 3y agoThe question is how accurate is cell tower triangulation?
- JohnFen 3y agoIt depends on the area. In very dense areas, it can be more accurate than you expect. It's also possible that they triggered a GPS response that told them rather precisely where the phone is. I'm only speculating, of course.
- trollied 3y agoPhones don’t just use triangulation. Modern smartphones will also use GPS (A-GPS).
- miohtama 3y agoThis is about asking the cell network where the phone is. This is not about asking the phone where the phone is.
- JohnFen 3y agoI think the question was "how did the phone company know the location", and GPS may be part of the answer. In the US, E911 requires all phones to be able to report their physical location. Phone companies may use this ability to respond to police location requests. I don't know one way or another, but it seems likely.
- yellowsir 3y agokinda spooky you see your neighbours doors on your cameras :O
- trogdor 3y agoThat is plainly allowed under federal law. Pursuant to 5 U.S.C § 2703(c), a provider “may divulge a record or other information pertaining to a subscriber to or customer of such service (not including the contents of communications covered by subsection (a)(1) or (a)(2)”…“to a governmental entity, if the provider, in good faith, believes that an emergency involving danger of death or serious physical injury to any person requires disclosure without delay of information relating to the emergency.”
- phyllistine 3y agoNo one is arguing that it's illegal, OP only said its 'spooky', therefore bad. Sometimes bad things are plainly allowed by federal law.