Legal "Realism"

In a past post, I talked about the troubling issue of tense in the legal status of those who commit crimes. We "presume them innocent" until found guilty by a jury or other sanctioned legal body. But this seems like nonsense talk because it's the crime that makes them guilty, not the judgment. Also, I mentioned that the doctrine would not make sense of legal mistakes. Judges, juries, prosecutors, police, etc can make mistakes and thus on occasion, when legal rulings are overturned, it would seem that people can be exonerated in the full meaning of that term.

I just found out that the doctrine that legal rulings by legit legal institutions are what makes the legal standing (and not as opposed to actual state of affairs of events which makes the case of guilt or innocence, e.g.) is called (absurdly) 'legal realism'! This is almost the opposite of moral realism which basically says that the rights or wrongs are not determined by what people or institutions say is right or wrong but posits moral facts of the matter independent of what people say which does determine (are the "truth-makers") of moral claims.