I agree that tossing someone under the bus whose done, or perhaps even contemplated nothing wrong is manifestly unjust at the same time onlookers who suspect wrongdoing aren't investigators and waiting until they are absolutely certain before contacting proefessional investigators to determine if wrongdoing occurs can also lead to gross miscarriages of justice particularly when lack of certainty can be abused as a convenient alibi. It's thorny, I don't know what the right balance is.