Yet this tragic accident will now set a precedent and finally start to scratch the delicate unspoken question:
Who is responsible now?
In law you split that into criminal and civil. Very unlikely there will be any criminal charge, hence no criminal liability but it’s possible.
Civil liability is more interesting, but if the deceased’s estate brings suit it opens up a can of worms in the discovery process. Every internal communication, prior incident, etc...
At the end of the day it’s not much different than any other vehicular fatality case, but there will be a defective product component (again nothing unheard of in the case of vehicular fatalities). At the end of the day the car will be insured for accidents, so we will probably learn more about the insurance coverage for self-driving cars.
Like my comment says, let's wait until we have facts before passing judgement.
But from this distance, things don't look good for the technology or the future of autonomous trials on public roads.
The evidence that due care was not taken will pretty much be the existence of the fatality.
There surely will be video, from the car itself and also perhaps third party security or traffic cameras. The level of carelessness we are going to have to see in order for a jury to blame the victim will be pretty high.
As for a fatality proving that due care was not taken, I agree. It doesn't tell you who failed to take due care though.