I think they have hung their accusation on NSA not using the FISA Act for its surveillance. What they are saying in terms we can understand better (but they refuse to see) is that if a suspected gangster's phone is tapped - legally - the FBI would still be breaking the law by not having a warrant for each person that the gangster was talking to.
The Dems are squealing that there is no warrant for the American "citizen" on the American side of the conversation with AlQueda. "Ordinary" Americans want NSA to do every trick they can to learn what our enemies are planning for us HERE INSIDE THE USA.