Just another reason to consider cell phones harmful. “Give me every phone in this area in this time window!” is not in the slightest bit compatible with a sane interpretation of the 4th Amendment…
This isn’t restricted to smart phones. They can already request the same info (broadly download everyone using a cell phone radio) on a cell tower basis. I’d suspect that there are so many towers in/around the capital that they can pinpoint your location just as good as gps, if not better (i.e. indoor micro/picocells).
That said, I can see them requesting the info on the basis of “matching pictures to people is hard” and to try and find people who turned their cell modems off, but left gps on.
but even gps doesn’t prove that you were there, only that your phone was. It is still only circumstantial proof in a court.
That said, I agree that this “law enforcement” power is used excessively and warrants are handed out too quickly/easily.
but I think it’s an alarmist article telling me nothing new.