Consider two cases: Situation A, and Situation B. In both, someone decides to kill her hated enemy. She finds the weapon of choice. She tracks her target’s movements. She finds the perfect moment, makes her move, and completes the kill… in Situation A. In Situation B, she slips up at the last moment, is subdued by the would-be victim, and the murder is never completed. In both situations, she had the same intent and would have caused the same outcome had she achieved her own goals. Only incompetence or bad luck caused the murderer to fail in Situation B, not a change of heart. Yet Situation A and B are treated very differently in courts of law. The corresponding punishment disparity is severe, often by a factor of 10.

But is there actually any moral difference between the two actions, or is one simply a case of moral luck? Does competence have any bearing on morality? If a bystander were to morally evaluate the assailants in Situation A and Situation B, he would probably assign more moral blame to the assailant in the former situation. Her course of action resulted in a death, whereas the course of action taken in Situation B resulted in no real harm. It is tempting to think that the first assailant is morally worse than the second because her actions produced a worse outcome. It is hard to conceptualize the objective morality of these two actions, perhaps because the results are so different, but, in our hypothetical, it essentially all comes down to chance.

Philosopher Thomas Nagel refers to this as “moral luck.” He writes that moral luck has no place in objective notions of morality because “Prior to reflection it is intuitively plausible that people cannot be morally assessed for what is not their fault, or for what is due to factors beyond their control.”

Let’s examine a less hypothetical example. Instead of our would-be murderer, consider a controversial case from last year. A 55-year old man in Houston, Texas was awakened by his 4-year-old son at 2:20 a.m. and told that there was someone in his 16-year-old daughter’s bedroom. The father then grabbed his gun and entered the bedroom. He found his daughter in bed with a boy and confronted him. His daughter did not see that her father was holding a gun. Perhaps embarrassed and scared of how her father would punish her, she lied and said that she did not know the boy. Allegedly, the father told the boy not to move, but then saw him reach for something and fatally shot him. His daughter later confessed that she had snuck the boy, who turned out to be her boyfriend, into the house.

Not surprisingly, the reflexive instinct of the media and the general population alike was to crucify the teenage girl for her lie and for the death that it caused (although some were more sympathetic). But what about moral luck (or the lack thereof)? The lie she told was wrong, and obviously had disastrous consequences — far worse than she imagined. But she was a mortified and frightened teenager who went into panic mode and lied to her father, as many of us have, in order to save face. The very worst consequences of her lie, she probably expected, would be the boy being thrown out of the house; perhaps the cops would have been called. Surely, she did not expect nor even consider that her lie would cause her father to kill her boyfriend — most of us would not either. It would have been better if she had, prior to telling the lie, soberly reflected on all possible consequences of that action, but that is unrealistic.

This same situation has likely occurred thousands of times without a fatality, and there was probably little reason to believe that this one would be any different. But she got unlucky.

Instead of looking purely at outcomes, we should consider the morality of an action based on its expected value: the consequences that a reasonable person could expect from a given action. That should be reflected in the way we punish and reward people. Besides being unfair, it’s pretty useless to punish people who, through immense bad luck, cause more harm than they could reasonably have anticipated. They cannot prevent this from happening again. And it’s also dangerous to not severely punish those who intended great harm, but couldn’t manage it (this time).

Objectively assigning moral blame is a difficult thing to do, and when victims are involved it gets much harder. But luck should be considered separately from morality. Just as a teenage girl does not deserve to have her life ruined because of her bad luck, the incompetent murderer is no less culpable simply because she happened to slip. There is a human need to blame things or people for every bad outcome — to look for a reason where there may not be any (this is sometimes called the Just World Fallacy, and it often makes people believe that others deserve the terrible things that happen to them, even if they had no control over those things), but this response is not morally rational. The boy’s death certainly is a tragedy, but “we don’t live in a play, not all tragedies need villains” and not all villains cause tragedies.

Contact Claire Zabel at czabel ‘at’ stanford.edu and Joseph (Joey) Zabel at joezabel ‘at’ stanford.edu.