In general I give people the benefit of the doubt (in any crime/action I'm not sure why you decided to limit it to sex crimes). There's evidence against Skupin for both charges against him I believe he is guilty, and the court will likely find him guilty. Similarly it'd be highly unlikely and absurd for the dozens of women against Cosby to all be lying. I believe he is guilty as well. I'm not in a situation where I'm deciding on who raped who on a daily basis (I avoid those horrid parts of the internet where people feel the need to take sides on every rape case) so I find it bizarre that you are limiting this discussion to sex crimes. I also don't believe the majority of people in prison are innocent. A better comparison would be the majority of people suspected. Either way it's not about majority it's about the rights of the person.

An less outrageous and more plausible example that would actually apply to me in my every day life is if I was missing something from my wallet. I wouldn't instantly presume guilt towards my roomate taking it I'd establish parameters and theories on what happened to it then clear them out before I go to her with the accusation. Similarly if my girlfriend is acting suspicious I'm not going to accuse her of cheating unless enough has swayed/been proven to me that she is. Only after I am certain beyond a reasonable doubt would I accuse of that.

In my perception/world view I give people the benefit of the doubt unless I'm convinced that they are not innocent. I'm not asking for a top prosecuter just enough to sway me from my natural stance. I'm not a judge, nor am I currently a juror. I'm just a guy who hopes for the best in people and will give them the benefit of the doubt unless I've been given sufficient reason not to. I also believe court of law must prove guilt beyond reasonable doubt and not innocence beyond reasonable doubt. Maybe that's silly to some people here but that's my mindset and I have no qualms, regrets, hesitations, or remorse over it.