# IS cell phone "ping"ing the same system used by 911? **URL:** \ **Category:** Factual Questions\ **Created:** [June 10, 2013, 4:20pm UTC](https://boards.straightdope.com/t/is-cell-phone-ping-ing-the-same-system-used-by-911/660632 "2013-06-10T16:20:17Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![dstarfire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dstarfire/32/5762_2.png) [@dstarfire](https://boards.straightdope.com/u/dstarfire)\ **Post date:** [June 10, 2013, 4:20pm UTC](https://boards.straightdope.com/t/is-cell-phone-ping-ing-the-same-system-used-by-911/660632/1 "2013-06-10T16:20:17Z")
There’s been a lot of talk recently about law enforcement pinging cell phones to track the users location. Is this the same system that carriers were required to implement so 911 operators and first responders could determine a callers location? ---
**Author:** ![Reply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/reply/32/15952_2.png) [@Reply](https://boards.straightdope.com/u/Reply)\ **Post date:** [June 12, 2013, 8:24am UTC](https://boards.straightdope.com/t/is-cell-phone-ping-ing-the-same-system-used-by-911/660632/2 "2013-06-12T08:24:28Z")
E911 uses a combination of GPS and cell tower location to find the appropriate agency to call and also to let them know where you are, but theoretically this only happens when you purposely place a 911 call. Law enforcement (or your favorite three-letter agency) can [demand your cell tower location](http://gizmodo.com/5934934/court-rules-that-cops-can-track-your-phones-location-with-no-warrant) from the phone companies, but whether they can remotely activate your GPS receiver and track you more precisely with that is harder to answer. It’s technologically feasible to write software (or firmware) to do so, but it would drain battery life quicker and would risk being discovered by people who work on Android. It’s possible that said 3LA is nonetheless doing this and forcing gag orders upon anyone who’s proven it, but hey, just because you’re being watched doesn’t mean you have to be paranoid. It is probably easier for them to just subpoena/warrantlessly borrow more precise location data from third party services, such as your geotagged photos from Facebook/Google+/Picasa/Flickr, or your Google Latitude history, or your last Yelp/FourSquare check-in, or your last Google Maps lookup, or the last few WiFi hotspots your phone did a Google Search from, etc. Your phone is pretty much constantly vomiting its ID and location to half the world. If you don’t want it to be tracked, don’t carry it with you. And wear a mask. ---
**Author:** ![Wizard\_One](https://avatars.discourse-cdn.com/v4/letter/w/6a8cbe/32.png) [@Wizard\_One](https://boards.straightdope.com/u/Wizard_One)\ **Post date:** [June 13, 2013, 7:39pm UTC](https://boards.straightdope.com/t/is-cell-phone-ping-ing-the-same-system-used-by-911/660632/3 "2013-06-13T19:39:28Z")
> [@Reply](#): > > E911 uses a combination of GPS and cell tower location to find the appropriate agency to call and also to let them know where you are, but theoretically this only happens when you purposely place a 911 call. > > Law enforcement (or your favorite three-letter agency) can [demand your cell tower location](http://gizmodo.com/5934934/court-rules-that-cops-can-track-your-phones-location-with-no-warrant) from the phone companies, but whether they can remotely activate your GPS receiver and track you more precisely with that is harder to answer. It’s technologically feasible to write software (or firmware) to do so, but it would drain battery life quicker and would risk being discovered by people who work on Android. It’s possible that said 3LA is nonetheless doing this and forcing gag orders upon anyone who’s proven it, but hey, just because you’re being watched doesn’t mean you have to be paranoid. > > It is probably easier for them to just subpoena/warrantlessly borrow more precise location data from third party services, such as your geotagged photos from Facebook/Google+/Picasa/Flickr, or your Google Latitude history, or your last Yelp/FourSquare check-in, or your last Google Maps lookup, or the last few WiFi hotspots your phone did a Google Search from, etc. Your phone is pretty much constantly vomiting its ID and location to half the world. If you don’t want it to be tracked, don’t carry it with you. And wear a mask. It’s been a well described capability of various intelligence agencies to turn on and off cell phones, make them appear off and be transmitting what the microphone detects and turn on and off applications on smart phones, such as GPS. They, of course, end up doing so from the carrier or from the cell tower. E911 uses AGPS, which isn’t GPS, but cell tower position locating to resect one’s position. ---
**Author:** ![TimeWinder](https://avatars.discourse-cdn.com/v4/letter/t/bcef8e/32.png) [@TimeWinder](https://boards.straightdope.com/u/TimeWinder)\ **Post date:** [June 13, 2013, 7:48pm UTC](https://boards.straightdope.com/t/is-cell-phone-ping-ing-the-same-system-used-by-911/660632/4 "2013-06-13T19:48:57Z")
> [@Wizard\_One](#): > > It’s been a well described capability of various intelligence agencies to turn on and off cell phones, make them appear off and be transmitting what the microphone detects and turn on and off applications on smart phones, such as GPS. Sure, but if we’re going to take documentaries like CSI, Homeland, and Get Smart as proof, then it’s also well-described that it takes 30/60 seconds to trace a call (hint – it doesn’t.) Building such a capability into every phone doesn’t pass the sniff test. They’re made by a variety of vendors, many overseas. The way you’d do this on an iPhone would be different from Android (and probably different for many Android devices from each other), different from Blackberry, etc. – especially the “turn on and off applications on the phone” and “transmit while being turned off.” I can’t prove that they’re not doing this, of course, via some gagged mandate to the device makers, but that seems like the sort of thing that would have been found by now if it were present – there’s certainly enough people looking for it. ---
**Author:** ![Iggy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iggy/32/3364_2.png) [@Iggy](https://boards.straightdope.com/u/Iggy)\ **Post date:** [June 13, 2013, 11:04pm UTC](https://boards.straightdope.com/t/is-cell-phone-ping-ing-the-same-system-used-by-911/660632/5 "2013-06-13T23:04:35Z")
\*\*Pinging \*\*the phone generally refers to locating a phone that is turned on but not currently making a call. Some 9-1-1 centers have the capability to send a command to the callers phone to \*\*retransmit \*\*its position data. This only works while the call is still active. And about 15% of 911 centers still have absolutely no way to get position data _at the time of the call_ if the caller is unable to provide an address. They can then go through the process to request the phone company ping the caller’s phone, but that takes time. ---
**Author:** ![Reply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/reply/32/15952_2.png) [@Reply](https://boards.straightdope.com/u/Reply)\ **Post date:** [June 14, 2013, 3:17am UTC](https://boards.straightdope.com/t/is-cell-phone-ping-ing-the-same-system-used-by-911/660632/6 "2013-06-14T03:17:41Z")
> [@Wizard\_One](#): > > E911 uses AGPS, which isn’t GPS, but cell tower position locating to resect one’s position. Do you have a cite? AGPS is the use of cell tower trilateration to aid in initial GPS lock-on, not the name of an independent radiolocation technology. Some phones can use the same method (not by that name) to acquire your rough location, but E911 can (and increasingly must) use actual GPS (meaning satellites) or other handset-based locating ([cite](http://www.fcc.gov/document/fcc-strengthens-e911-location-accuracy-wireless-services)): > [@](#): > > Wireless carriers have historically provided E911 location information by one of two methods: “handset-based,” where location information is generated by GPS or similar technology installed in the caller’s handset, or “network-based,” where location information is generated by triangulating the caller’s wireless signal in relation to nearby cell sites in the carrier’s network. Not sure what the “other” is (maybe GLONASS?) but it’s specifically differentiated from network-based radiolocation like AGPS. Other cites: [Verizon E911 and GPS](http://support.verizonwireless.com/faqs/Wireless%20Issues/faq_e911_compliance.html) [AGPS vs GPS in the context of E911 radiolocation](http://www.rcrwireless.com/article/20120424/opinion/reality-check-new-fcc-proposed-rules-may-lead-to-better-location-accuracy-for-e911-calls/)