"I can give you an example I've seen mentioned in several places. My automated car is confronted by an 80,000 pound truck in my lane. Now the car has to decide whether to run into this truck and kill me, the driver, or to go up on the sidewalk and kill 15 pedestrians. That would [have to] be put into the system,” Hart said.
That's a false dichotomy.
The correct answer is that an AI (or any human driver worthy of keeping her licence) faced with driving in a crowded urban environment will reduce the speed so that the car can come to a stop safely within the available space if a previously invisible, but reasonably foreseeable obstacle appears ahead.