All kidding aside, 40 years from now we'll still be driving our own cars because programmers won't be able to help a car decide if it is allowed to avoid a collision that will kill a driver by swerving onto a sidewalk and killing two pedestrians.
Self-driving cars won't even attempt to make decisions like that. If faced with a no-win situation, they'll default to trying to stop as quickly and safely as possible. If that still results in a crash, the car's black box should contain enough sensor data to prove that the crash was either a freak of nature (mechanical failure, etc.) or someone else's fault.