All it takes is just one overzealous prosecutor, asshole at work, jerk neighbor, dumb luck, or thinking for one moment we are above the law or smarter than those investigators who every day go to work and figure out who did what. Even if those laws are unjust or unconstitutional. I've known guys who went to prison and still do. Most of them admitted they did wrong and got caught. The ones who won't admit that, I occasionally wonder if what they say about their alleged innocence might be true but i don't dwell on it much.