Self-driving cars are already cruising the streets. But before they can become widespread, carmakers must solve an impossible ethical dilemma of algorithmic morality.

How should the car be programmed to act in the event of an unavoidable accident? Should it minimize the loss of life, even if it means sacrificing the occupants, or should it protect the occupants at all costs? Should it choose between these extremes at random? (See also “How to Help Self-Driving Cars Make Ethical Decisions.”)

The answers to these ethical questions are important because they could have a big impact on the way self-driving cars are accepted in society. Who would buy a car programmed to sacrifice the owner?

These problems cannot be ignored, say the team: “As we are about to endow millions of vehicles with autonomy, taking algorithmic morality seriously has never been more urgent.”