Hugh

"Just because it's official doesn't mean it's true" is correct - however, when three separate inquiries (one of them French, one by the Met, and the last being a formal inquest) come to the same conclusion, and hundreds of journalists from multiple countries have done in-depth investigations, and when governments can't even "cover up" their own wrong-doings, do we really think that if this had happened, with lots of people involved in the planning and cover-up, something wouldn't have been leaked before?

People aren't believing it because it's official and they are gullible - they believe it because they have followed through a chain of events, read about the investigations into them, and agreed with the official verdict.

Occam's Razor - usually the simplest explanation is also the most likely.