The driverless dilemma: Who does your car choose to save?

Imagine cruising down the highway in your fully autonomous car. You’re reading a book, catching up on emails, or simply enjoying the view, completely trusting the vehicle’s advanced algorithms. This is the future we’ve been promised—a world with fewer accidents, less traffic, and more freedom. But what happens when things go wrong? In a split-second, unavoidable crash scenario, your car must make a choice. Does it swerve to avoid a group of schoolchildren, sending you into a concrete barrier? Or does it prioritize your safety, at the cost of others? This isn’t a scene from a sci-fi movie; it’s the modern incarnation of a classic philosophical puzzle known as the trolley problem, and it’s a dilemma that engineers and ethicists are grappling with right now.

The digital trolley problem

The original trolley problem is a thought experiment in ethics. A runaway trolley is about to kill five people tied to the main track. You are standing next to a lever that can switch the trolley to a side track, where there is only one person tied up. Do you pull the lever, actively causing one person’s death to save five? For decades, this has been a staple of philosophy classes. Today, it has rolled out of the classroom and onto our roads.

For an autonomous vehicle (AV), this is not a hypothetical. It’s a potential programming directive. Picture this: your self-driving car’s sensors detect a sudden brake failure as you approach a crosswalk. Ahead of you are three pedestrians. The car’s AI calculates that it cannot stop in time. It has two options:

• Continue straight, hitting the three pedestrians.
• Swerve sharply onto the sidewalk, hitting a single person but avoiding the group.

Now, let’s add another layer of complexity. What if the only alternative to hitting the pedestrians is to swerve into a wall, sacrificing you, the occupant? The car’s decision, once a matter of human reflex and panic, is now a pre-determined, coded choice. Who should make that call? The programmer? The car owner? The government? This transition from a philosophical puzzle to a real-world engineering challenge forces us to confront difficult questions about the value of life and the nature of responsibility.

Programming morality: Utilitarian vs. self-preservation

When faced with an impossible choice, how should a machine be programmed to react? Broadly, two major ethical frameworks come into play, each with profound implications for the future of autonomous driving.

The first is utilitarianism. This ethical theory suggests that the best action is the one that maximizes overall good and minimizes harm. In the context of an AV, a utilitarian algorithm would be programmed to save the greatest number of people. If it must choose between hitting one person or hitting five, it will always choose to hit the one. If it must choose between sacrificing its single occupant to save a group of pedestrians, utilitarian logic dictates that the occupant is sacrificed for the greater good. While this sounds noble in theory, it creates a significant commercial problem: Would you buy a car that is programmed to kill you?

The opposing approach is rooted in deontology and self-preservation. A deontological framework follows a strict set of moral rules, regardless of the outcome. For a car, this rule might be “protect the occupant at all costs.” This aligns with our natural survival instincts and the traditional role of a vehicle as a protective shell for its passengers. This model is far more appealing to a potential buyer, who expects their multi-thousand-dollar purchase to prioritize their safety. However, it means the car would be programmed to sacrifice a crowd of people to save its owner, a choice that society as a whole may find morally unacceptable.

Public perception and the consumer’s choice

The conflict between these ethical models is not just theoretical; it’s reflected in our own conflicted feelings. Researchers at MIT conducted a massive global survey called the “Moral Machine,” which presented millions of people with various AV crash scenarios. The results revealed a fascinating paradox. Overwhelmingly, people agreed that cars should be programmed with utilitarian ethics—to sacrifice one to save many. They believed this was the most ethical choice for society.

However, the study also asked what kind of car they would personally buy. The answer was the opposite. Most participants preferred to purchase a car that would protect them and their passengers at any cost, even if it meant causing more harm to others. This creates a classic social dilemma: we want everyone else’s car to be selfless, but we want our own car to be selfish. How can car manufacturers possibly navigate this? Advertising a car’s “utilitarian crash algorithm” is commercial suicide, while openly promoting a “self-preservation mode” could open them up to endless lawsuits and public outrage.

Regulation and the path forward

While the dramatic “trolley problem” scenario is statistically rare, it’s a critical edge case that must be addressed before AVs can be widely adopted. The primary goal of self-driving technology is, after all, to be vastly safer than human drivers and prevent accidents from happening in the first place. Yet, for those unavoidable moments, a clear legal and ethical framework is essential.

Governments are beginning to step in. Germany, for example, has already established a set of ethical guidelines for AVs. Their rules state that in an accident, the system must always choose to avoid injuring people over causing property damage. Crucially, the German guidelines also forbid the car’s programming from making decisions based on personal characteristics like age, gender, or disability. In essence, all human lives must be treated as equal. This approach attempts to create a baseline of fairness, but it doesn’t fully resolve the dilemma of choosing between one life and another. A globally accepted standard is still a long way off, complicated by differing cultural values. The path forward will require a careful blend of robust regulation, continued public debate, and technological transparency.

Conclusion

The rise of the autonomous vehicle holds the promise of a safer and more efficient world, but it places us at a unique ethical crossroads. The driverless dilemma forces us to translate abstract moral philosophy into lines of code, deciding in advance who a car should save in an unavoidable accident. We are caught between the selfless logic of utilitarianism, which serves the greater good, and the deeply ingrained instinct for self-preservation, which dictates that our own car should protect us above all else. This paradox is reflected in public opinion, leaving manufacturers and regulators in a difficult position. Ultimately, the debate over how to program a car is a reflection of our own societal values. How we solve the trolley problem for our machines will say a great deal about who we are and what we stand for.

Image by: Kaique Rocha
https://www.pexels.com/@hikaique