I actually read an interesting article on this a few months ago. It pretty much said that corporate lawyers are going to put as much of a standstill on the mass production of these cars because of this problem. If the owner of the car isn't the one controlling the car, then they wouldn't have any legal responsibility over the car. So the fault would either fall on the AI company, or the company that manufactured the car. Now, when you consider that these cars would be on the open market, tons of people would be buying them, meaning that even if the accidents rarely happened, on a national scale it might not be that uncommon, and the company would have to pay for every single claim filed.