You're right, the system is not fair, and it's FAR from being perfect. The "innocent until proven guilty" part bothers the heck out of me. But the story doesn't end with me or you. Recall that there are actual criminals in the world and "the system" is trying to balance public safety with the rights of the individual. It's tricky, and is just becoming trickier.

I don't know how to solve it, but the answer can't be stripping our law enforcement officers completely of the right to investigate what a person did or is doing.