I can see initially there will be some rule that the ‘driver’ must always be ready to manually override and take control and therefore the ‘driver’ remains the person responsible for the car
This is defined as level 3 AD and is a complete legal nightmare, this is where Tesla are today.
Level 3: Within known, limited environments (such as freeways), the driver can safely turn their attention away from driving tasks, but must still be prepared to take control when needed.
The next level is where the industry needs to get to:
Level 4: As level 3, but no driver attention is required. Outside the limited environment the vehicle must be able to enter a safe fallback mode – i.e. park the car – if the driver does not retake control
e.g. having a safe stop fall back option if the driver does not take control