We'll never have a true answer, I think, if we're to look at it based soley on the facts. It's easier than people think to plant evidence, doctor it, etc. Even patsies have patsies.
If you question who is most likely to have done it, you end up going on a chase for potentially the wrong person and the real killer gets away with it. If you widen the range of suspects, the real killer can, with some ammount of comfort, maneuver him/herself away from the crime.
History may be largly inaccurate, for that matter. How do we know George Washington was real, for example? How do we know our own American history is exacty as people state in history books, notes, journals, and dairies from these powerful figures? None of us were there, in the very early stages.
It could be the whole truth, the half truth, or a complete lie. I would like to believe its all the truth, but the potential exists for it being half true or not at all. History and important events are very fickle and capracious, as they are only as reliable as the contrasting opinions of the people talking about them, interpreting them, and spreading them down through history.
