In vehicles with self-driving features, who takes the blame for a crash? Tesla may have an answer. The Wall Street Journal understands that the turn signal activation of the Model S' car-passing autopilot is largely about liability. When you flick the signal stalk, you're conveying your intent -- if the vehicle smacks into someone else as a consequence, you're likely at fault. This is unfortunate if it leaves you on the hook for an accident that was out of your hands, but it could also save you from requiring special registration to get your semi-autonomous machine on the road.