Here's the thing. If the first accident that results in a lawsuit is with a private car owner, then if the owner of the self driving vehicle ends up on the hook, it will be for far less since they're just some person. If the first lawsuit is against a large company with several of these, then it's likely to come back higher, and the first court case sets at lot for future ones. This is what we libertarians calls, impeding progress through fear of litigation and anti-corporate sentiment, or "fuck lawyers" for short.