Tyranny Of Secrecy:
If you want to conceal the information, just classify it. The CIA just conceals the information they give by classifying evidence and documents.
I'll give you some examples here; where Congress demanded the torture report that the CIA released what they were engaged in. The torture report that the CIA provided Congress was completely blacked out. They provided it but it was completely blacked out. When you look at what happened with Fast and Furious when the CIA was running drugs and guns to the cartel on the border, you can see the document in pictures online where the information was completely blacked out also. Do you see a problem with that? The supposed 911 Report which was supposed to be transparent so the American people could know what happened in 911 and frankly, we don't know a thing about it because a criminal investigation was never done, and anyone that has been trying to do one has been stifled in their lives if not disappearing from the face of earth. And, what is done, you get an entirely different picture, but - the 28 pages of the so-called transparent 911 Report you can see for yourselves has been blacked out. George W Bush ordered that those pages in that Report be blacked out, indicating that that was Saudi Arabia's connection to 911, Saudi Arabia is tied at the hip with the CIA and our intelligence services and most injections of the Congressmen that I've seen involved, they think that's what that was. So, this is the modus operandi, and how they go about doing it. If the CIA wants to classify information and the Congress demands through their power, and the oversight committee's they demand information - well, you can see what they get is blacked out - not transparent information at all.
Nobody can stop them, and nobody challenges them, because they know they don't have the authority with the CIA, and nobody can demand that they take the black outs off of this important information. Essentially, not only don't people have the balls to ask for the real report, but they simply won't give it. This is the ultimate power that the CIA has, and it's absolute tyranny.