The folly of trolleys: Ethical challenges and autonomous vehicles

Often when anyone hears about the ethics of autonomous cars the first thing to enter the conversation is “the Trolley Problem.” The Trolley Problem is a thought experiment where someone is presented with two situations that present nominally similar choices and potential consequences (Foot 1967; Kamm 1989; Kamm 2007; Otsuka 2008; Parfit 2011; Thompson 1976; Thompson 1985; Unger 1996). Situation A (known as Switch), is where a runaway trolley is driving down a track and will run into and kill five workmen unless an observer flips a switch and diverts the train down a sidetrack that will only kill one workman. Situation B (known as Bridge) has the observer crossing over a bridge, where she sees that the five people will be killed unless she pushes a rather large and plump individual off off the bridge onto the tracks below, thereby stopping the train and saving the five. Most philosophers agree that it is morally permissible to kill the one in Switch, but others (including most laypeople) think that it is impermissible to push the plump person in Bridge (Kagan 1989). The case has the same effects: kill one to save the five. This discrepancy in intuition has led to much spilled ink over “the problem” and led to an entire enquiry in “Trolleyology.”Applied to autonomous cars, at first glance, the Trolley Problem seems like a natural fit. Indeed, it could be the sine qua non ethical issue for philosophers, lawyers, and engineers alike. However, if I am correct, the introduction of the Trolley is more like a death knell of any serious conversation about ethics and autonomous cars. The Trolley Problem detracts from understanding about how autonomous cars actually work, how they “think,” how much influence humans have over their decision-making processes, and the real ethical issues that face those advocating the advancement and deployment of autonomous cars in cities and towns the globe over. Instead of thinking about runaway trolleys and killing bystanders, we should have a better grounding in the technology itself. Once we have that, then we see how new—more complex and nuanced—ethical questions arise. Ones that look very little like trolleys.