Since the IPCC knew about the bogus Global warming data BEFORE Copenhagen, why didn't they reveal the truth?

The job of bureaucracies is to grow and the only way they can expand their political power is with doomsday proclamations. The truth is they are nothing but a leftist political organization and everything they do is spread their lies and try to convince the gullible about significant human caused warming. Their lies or ridiculous exaggerations if you prefer have been blatantly obvious for several years to anyone with any common sense and basic knowledge of the subject beyond Al Gore's third grade level science.