Surely that only happens when the phone user dials 911 ?
Tons of "free" and crapware apps are also recording location, and sending it to data brokers.
https://www.wired.com/story/jeffrey-epstein-island-visitors-...
https://5g-tools.com/5g-nr-timing-advance-ta-distance-calcul... shows an example of the parameters necessary. I don't think you can get your smartphone to dump those stats for you, but the granularity of the individual distance measurement is in the tens of centimeters.
Of course this strongly depends on cell infrastructure being placed precisely, continuously updating correction factors, and a bunch of antennae being around the target to get measurements for, but in most cities that isn't much of a challenge if the operator is working together with whoever wants to spy on citizens.
The last time I checked, that included Google Play Services, and some of their iOS apps.
When you dial 999 it forwards your phone's GPS location if it has a lock to the provider, who then forwards it on to one of the 999 call handling centres in the UK, who then in turn forward that on to the appropriate emergency service control room. All the various services use various different products for telephony and dispatch but they will show the incoming location, and often will prepopulate an incident with the location.
The system that does this is called "EISEC" - Enhanced Information Service for Emergency Calls - and has a lot of cool stuff defined in the spec (which is publically available! You can just go and read it! BT offer a "Supplier's Information Note" with the protocol and details of how the information is encoded) that also handles calls from landlines. These are easy - your telephone provider knows where you live. OMG! The phone company know where I live? Yes, dumbass, they pulled a wire right into your house, of course they know where it is. For VoIP the situation is a little different but you can notify your VoIP provider of the location that the number is being used at, and it'll inject that into the EISEC request.
You can do other cool stuff like if you've got fixed mobile telephone in a vehicle, you can assign the make, model, registration number, colour, and so on in the EISEC database, so given a call from a phone number they know what car they're looking for. No-one uses this.
The very great majority of calls coming in to 999 are from mobiles. It's extremely rare to get one from a landline.
None of the providers use triangulation for determining where a phone is, it's all GPS.
That's true, but you can always be triangulated down a couple hundred meters by figuring out which towers you're connected to.
This is a specific service inside the phone that looks for messages from the carrier requesting a GPS position, it could just refuse, or lie. It's not the same as cell tower triangulation.
I think it would be sufficient to just have a log of this information being queried, and cases where the information has been pinged without a legitimate use case would the be investigated.
Last time I called 911 (well, it's 112 in my country) my android phone asked if I want to provide gps coordinates. I did, but they still asked for address, so probably this is not integrated/used everywhere.
https://rapidsos.com/public-safety/unite/
When the call comes in they can click a button and query RapidSOS for current 911 calls for that number and pull the information inwards.
https://www.baycominc.com/hubfs/2025%20Website%20Update/Prod...