We have a system that is designed to let most guilty men free. A system that unashamedly says it's better to let 99 guilty men free than to convict 1 innocent man. It's important to always remember that.
"not guilty" and "innocent" are very different things. Most guilty people are never found guilty of their crimes, that doesn't mean they are innocent though.
unfortunately there are still plenty of innocent people found guilty.
Maybe that's why so many people love the idea of religion and God, because it's comforting to think that the guilty will face SOME sort of justice eventually. but they won't, they just get away with it.
I'm just speaking in general, not about this case specifically.