According to the 14th amendment of the Constitution a person is "presumed" innocent until proven guilty in a court of law. It is a legal principle not a social principle.
In the Latin: ei incumbit probatio qui dicit, non qui negat - “the burden of proof is on the one who declares, not on one who denies”, means that the justice system declares the charges against him, not me. So it is the Justice System who must bear the burden of proof and treat him as though he is innocent. In other words the jail cannot house or work him as a convicted man. He cannot be subjected to punishment, torture, etc. Yes he can be held in secure lockup for his and my protection but not as a convicted person. His rights to interrogation, to representation/ counsel, trial, etc., are protected as are yours and mine.
I, on the other hand have no such burden. The 1st Amendment to the Constitution guarantees my right to free expression and free association, which means that the government does not have the right to forbid me from saying what I like and writing what I like. Therefore If I say I think he is guilty I cannot be held to some legal principle which negates my freedom of thought.
If I were to be called to the Jury, however, in order to serve I must be sworn in and then declare that I can render an impartial verdict based on the evidence and the law.
In this case I would have to decline on the basis that I have formed a prejudicial opinion based on the knowledge that I have.
That is my right.
So when someone says he is innocent until proven guilty, the only truth there is that is their own opinion and nothing more, unless they are part of the Law enforcement and Judicial system under which he is being charged and still it only applies to themselves.
So as for me, he is guilty and should serve the rest of his natural life. And I don't have to prove it. I am free to think and say what I please.
JMO