I read GM was called by police from a local town, which was involved in a high speed pursuit with a vehicle that happened to have Onstar. GM was able to shut the vehicle down using Onstar. I'm so happy my Tahoe doesn't have it.
they have been able to do that for quit some time, especially with stolen vehicles provided the thief was not wise enough to disable it.
I listen to my scanner all day usually all they have to track is a cell phone ping, that by far is used more than anything else, on rare occasions if they are really looking hard they will put a license plate alert on FLOCK (license plate reading system) and get a location usually in a fairly short period of time. Lojack comes up more often than using onstar
once they have a general vicinity to look they are able to find them quit often, criminals in general are not too bright, the smart ones rarely get caught
they have a few things up there sleeve around here GPS projectiles that stick to the bumper, drones with heat sensors, helicopter, dogs. If you can escape all that then you most likely had a head start.
once the battery technology increases the drones will be up 24/7 just to be ready all the time, they will monitor traffic and everything in between
then you can be scared....
"The technotronic era involves the gradual appearance of a more controlled society. Such a society would be dominated by an elite, unrestrained by traditional values (of Liberty). Soon it will be possible to assert almost continuous surveillance over every citizen and maintain up-to-date complete files containing even the most personal information about the citizen. These files will be subject to instantaneous retrieval by the authorities."