US Government Amasses Intimate Data on Millions of Americans Through Secret Purchases

The US government has been buying Americans' personal data in secret to gather intelligence on citizens.
Data brokers sell phone records, web browsing history, geolocation data and more to government agencies.
The huge trove of data could be misused and threatens civil liberties, experts warn.
Lawmakers are calling for rules around what data can be bought and how it's used.
The same data is also sold to private companies, foreign governments and others worldwide.