It should be 100% liability on the self-driving car. Only by doing that will there be enough incentive for the manufacturers to drive the accident rate down to

It should be 100% liability on the self-driving car. Only by doing that will there be enough incentive for the manufacturers to drive the accident rate down to zero (or in practice a low enough number that the cost to manufacturer of the remaining accidents is negligible). Less than 100% liability provides wiggle room, which car manufacturers will exploit to maximise profits over lives. With 100% liability manufacturers can still make a pile of money, but only if they have a low accident rate.