Cops have a secret, unaccountable system for tracking you by your cellphone, and they abuse it like crazy
by Cory Doctorow from on (#3Q1SX)
Securus Technologies markets a product to law enforcement that taps into realtime cell-tower data from mobile carriers to produce fine-grained location tracking of anyone carrying a phone; it is nominally marketed to find parolees and wandering Alzheimer's patients, but because it has no checks or balances, cops can query it willy-nilly to find anyone's location. (more")