"I don't know what the report is," Alexander cautioned, adding the NSA does not "have access to Google servers, Yahoo servers." He said the NSA is "not authorized" to do this, and instead, must "go through a court process."
http://www.politico.com/story/2013/10/keith-alexander-nsa-re...
Questioning him, under any circumstances, is useless. We need to get rid of him instead, and perform an independent investigation. However the circumstances under which such an independent investigation would be useful are limited. When East Germany started to fall, the Stasi started shredding everything they could get their hands on; organizations like this don't allow evidence to survive.
Politicians are often adept at replying very carefully to questioning by congress or courts so that they can be entirely truthful when answering your questions, all while avoiding telling you what you really needed to know because you never asked the right question.
If the article is correct, the NSA does not have that. What they have is an agreement that they can submit search terms and get matching data from a system operated by their British counterpart, GCHQ.
It is GCHQ who, per the article, has a direct tap somewhere inside Google's unencrypted datacenter-to-datacenter communications network.
The ideas is that US agencies supply the UK with technology and training, the UK collects sigint in the US with US knowledge, then shares intelligence with US agencies.
The US reciprocates by spying on UK citizens and sharing the intelligence with UK agencies.
That way US agencies can say they don't spy on innocent Americans on US soil. But it's just another elaborate deception.
Not that he would say Yes if we asked in the right way!