"How many cases of carjacking do you think will happen before crims realise that they may as well just walk into the Old Bailey and take a dump in the foyer?"
How many cases do you think will involve an unknown person due to baggy clothes, hoodie and scalf or mask?
Thieves have long ago figured out how to avoid detection and identification via the MkI eyeball, and will quickly figure out it's the same for car sensors. As for where they came from/went to? Across the road of cause. CCTV will track figures only so far, but a criminal learns to find the blind spots or where they can operate that has a slow response time, possibly because the roads are all blocked up by stationary self-drive cars waiting for the pedestrians to finish bimbling across the road.
The latter is my main concern: That self-drive cars will cause road congestion to the point that emergency response vehicles can't get through. Even with careful programming, unless the self-drive car knows to get out of the way of the ambulance/fire appliance as a priority and sod the pedestrian who has stopped infront of the car to see what's going on, the car will just sit there and obstruct the road while the pedestrian obstructs it's path.
There is a reason why we need drivers to be able to overrule the self-drive option: It's because rule may need breaking in event of emergency.