Another factor is, they demand that you prove the documents exist, first. Then they might search for them, and then they might give you an honest answer. If you ask for specific documents - and they won't help you find them in any way - and they are forced to admit they exist, and a judge orders them to release them, then they just censor them to hell and back.

That's why Wikileaks and other whistleblowers have done more damage than anyone. The documents were released unredacted and everything got dumped. That's why they have gone after Assange with fangs and claws, he bypassed their gatekeeping.