NSA Director is caught lying 14 times under oath under questioning by Hank Johnson (D-Georgia)

We know the NSA is routinely collecting ALL emails from American citizens as well as a large number of electronic transactions as well as other data. 

Here is the wired article that Hank Johnson refers to. 
http://www.wired.com/threatlevel/2012/03/ff_nsadatacenter/all/1 

There is plenty of other evidence from whistle blowers and various newspaper articles that the NSA Director was lying. 
E.G. William Binney and Thomas Drake - as well as the claims of Edward Snowden. 

See my previous article on the details of the NSA Mass Surveillance programs with the links to the relevant articles. 
http://ian56.blogspot.co.uk/2013/06/verizon-revelations-tom-clements.html

Update 06/13
The refutation of General Alexander's lies