All it does is notify you when police are known to be nearby.
One of the deterrent effects of police is never knowing where they are.
Strongly disagree. The main deterrent is knowing the police are in an area. Otherwise it falls into the category of being anywhere, so why not commit crime x here?
Another issue is that mass storage and scanning of communications does not lead to public disclosure of an individual's location.
Also incorrect, mass scanning of communications including metadata gives you not only locations of people, but patterns of movement. So every Tu evening at 7pm, you truck over to the YMCA for what appears to be an AA meeting, since there are several convicted and recently released DWI people there. How do we know they're DWI people? Because we know where they sleep every night and have cross-referenced that information against our criminal DB. The sad part? That's the only day you're free to meet John for racquetball. But now, thanks to that inconsequential scanning of communications, when you're pulled over next Sun coming home from Joe's house watching the Superbowl, and having a beer spilled on you, you're now heading for a DWI and prison because you've been tagged. You're innocent? Prove it.