One thing many people outside of science (and even within science) fail to understand about potential bias. Bias may exist even without any data faking whatsoever.
Research may yield results that are only part of a larger picture, and, indeed, looking like the opposite of the overall picture. Jokes about this are common with medical research.
If researchers know they will receive funding only if their results are favorable to one side, they will not choose research topics that could possibly yield a confounding result. Therefore, none of the studies are done that could refute the preconceived outcome.
On the other hand, it is my personal belief that this is not all that is going on with Dr. Hansen. He should be removed from his position and replaced by a scientist.
See #22.