In order to be convicted the Prosecutor would have to show the bus driver didn't care about being spit on which I think he proved otherwise. The driver didn't know what the passenger was going to do next, maybe get off the bus turn around and shoot him. Total self-defense in my opinion. Sickening, I hope anyone who convicts the guy of assault would do nothing after being spit on. Makes sense.
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Why build in the flood plain?