Well, if one believes the staged/crisis actors theories, just about anyone who had to be "in on it" for it to be true was on on it.
Conspiracy theories are more like conspiracy hypotheses, because there really isn't much evidence to back them up. I like them (not believe them) because they could be true. I mean, most of what we "know" wasn't observed directly by ourselves but was told/taught to us through media or other sources, many of whom didn't even observe it directly themselves.