If everybody sticked more or less to the rules and if there are no severe injuries/very costly damages, then it's really just compensation costs. I don't know

If everybody sticked more or less to the rules and if there are no severe injuries/very costly damages, then it's really just compensation costs. I don't know the exact situation in the US (also I'm no lawyer or something), but in Germany when some kind of Negligence is involved people can lose their drivers licence temporarily or forever, may have to pay fines (on top of compensations) or even have to go to jail. (Edit: also a costly Medical-psychological assessment may be needed afterwards to be able to drive again in the future.) Coming back to the costs, it's also interesting to say that insurances usually cover sums 1 - 20 millions. That's how much damage a single person can easily do with a car. It's said that it's a plus that self-driving cars are somehow interconnected and learning from each other. You may argue they are thus one entity and may have to be insured like that. Ok, but that's maybe a bit too esoteric now... ;)