Every response from the NSA and people speaking on their behalf, both before and after the Snowden leaks, has basically been

1. A denial that they have the "capability" to do [insert method of mass surveilance], leaving open the possibility that "capability" means legal authorization;

2. A quasi admission that maybe the surveillance happens (Clapper: "not wittingly").

In other words, "we're collecting everything, but we'll only inspect your data if you're not American, or have a relationship of any kind with someone who has ever contacted a terrorist suspect."