Here’s the dream: You want to go out to meet some friends for a drink, 30 miles from your house. You get into your autocar, set the destination, and then lie back for a quick disco nap so that you’ll be fresh enough for dancing afterward. The car drops you off at the restaurant and obediently takes itself off to the parking lot. It will come back to pick you up when you send an electronic signal that you’re ready. You can even have it drop off a friend who lives five miles beyond your house — after it’s dropped you off. It will be back in the driveway in time for your morning trip to the farmer’s market. …

Driverless cars will be safer and quieter. They will fetch you to your destination, and then trundle off to park themselves. They will all but eliminate the auto accidents that kill tens of thousands every year. I believe all this. But I’m still worried about the future of driverless cars, not because they’re technically impossible, but because the liability possibilities are enormous.

To see why, a brief primer on manufacturer liability. Currently, liability is limited by two things. On the manufacturer side, user negligence: If you run your car into a school bus, it is you, not the manufacturer, who is liable. Even if better brakes might have helped, the fact that you were going 50 in a school zone is probably going to make it hard for the plaintiffs to recover from a manufacturer.