"46 times" could well mean "Set up 46 separate devices throughout the county and collected all calls for four years", or perhaps "Left one device running for 46 contiguous months in the center of town", with the way these people work.
These give the impression that the use is targeted and for a limited time, but of course one can never be sure. I'd like to know:
* For how long was the device used in each incident?
* How was it deployed?
* How many other cellular devices were picked up?
* What happened to the irrelevant data collected?
[1] http://arstechnica.com/tech-policy/2015/04/fbi-would-rather-...
Spidey is an Android-based stingray (IMSI
catcher) detector that uses machine learning
to detect the presence of stingray devices
which can be used to eavesdrop on cellular
communication.
Also see http://codesign.mit.edu/category/macluguardian-project/
I don't know if they are lazy, authoritarian, or both.
Except that the department of justice is involved and they do their best to avoid such court cases that could determine legality of these activities.
It's probably time for society to have a discussion about this issue. Law enforcement can not protect us from ourselves if they don't know what we are doing. The War on Drugs pretty much mandates the use of secret surveillance for example. It's like asking a friend to help with your diet but at the same time forbidding them from looking in the cupboards or the fridge. If we don't like law enforcement snooping in our affairs then we should stop asking them to do so.