How do you teach an autonomous car when to hurt its passengers?

How do you teach a car when to self-destruct? As engineers develop and refine the algorithms of autonomous vehicles that are coming in the not-so-distant future, an ethical debate is brewing on what happens in extreme situations — situations where a crash and injury or death are unavoidable.
A new study in Science,"The Social Dilemma of Autonomous Vehicles," attempts to understand how people want their self-driving cars to behave when faced with moral decisions that could result in death.