would be decided on a case by case basis with logs from the car's computer.
If I was a car manufacturer and I knew that my log files would undoubtedly be used as evidence against me in a criminal negligence trial, I would think very hard about what I did and didn't put into those logs.
But if the car is in full auto mode the driver is not expected to pay attention or look at the road. Based on the situation the car thinks it can drive autonomously.
At least a partial liability will have to fall on the OEM that's why nobody is making any binding promises (including Tesla)
If I was a car manufacturer and I knew that my log files would undoubtedly be used as evidence against me in a criminal negligence trial, I would think very hard about what I did and didn't put into those logs.