[John Kelly](http://www.usatoday.com/story/news/nation/2013/12/08/cellphone-data-spying-nsa-police/3902809/):
> Armed with new technologies, including mobile devices that tap into cellphone data in real time, dozens of local and state police agencies are capturing information about thousands of cellphone users at a time, whether they are targets of an investigation or not, according to public records obtained by USA TODAY and Gannett newspapers and TV stations.
This article is exactly what you expect, exactly what is stated in the above quote. What it points out though is that once you make it “ok” for one government agency to spy on people, it starts to trickle down and be “ok” for all policing agencies to spy on people.
Now it’s not just about finding terrorists — it’s about finding kidnappers, murderers, and the guy who broke into the Sheriff’s car last night. And while most of those are noble causes, unchecked, the majority of use cases become personal vendettas and lines are blurred in the name of justice.