Being guilty before proven guilty is a thing in the real world.

As is being guilty and getting away with it. People do that all the time too.

And courthouses and judges don't have some monopoly into assessment of guilt. Just into its official identification and punishment.

(If the legal system had the monopoly, or some moral monopoly, of only it determining guilt, then how would we, as a society, judge the effectiveness or not of the legal system itself?)