Robert J Hartman in Aeon:
There is a contradiction in our ordinary ideas about moral responsibility. Let’s explore it by considering two examples. Killer, our first character, is at a party and drives home drunk. At a certain point in her journey, she swerves, hits the curb, and kills a pedestrian who was on the curb. Merely Reckless, our second character, is in every way exactly like Killer but, when she swerves and hits a curb, she kills no one. There wasn’t a pedestrian on the curb for her to kill. The difference between Killer and Merely Reckless is a matter of luck.
Does Killer deserve more blame – that is, resentment and indignation – than Merely Reckless? Or, do Killer and Merely Reckless deserve the same degree of blame? We feel a pull to answer ‘yes’ to both questions. Let’s consider why.
On the one hand, we believe that Killer deserves more blame than Merely Reckless, because it’s only Killer who causes the death of a pedestrian. Plausibly, a person can deserve extra blame for a bad result of her action that she reasonably could have been expected to foresee, and causing the death of a pedestrian by driving drunk is that kind of bad consequence. So, even though they deserve an equal degree of blame for their callous and reckless driving, Killer deserves more blame overall, because only Killer’s foreseeable moral risk turns out badly.
On the other hand, we believe that Killer and Merely Reckless must deserve the same degree of blame, because luck is the only difference between them, and luck, most of us think, cannot affect the praise and blame a person deserves. It would be unfair for Killer to deserve more blame due merely to what happened to her, because moral judgment is about a person and not what happens to her. So, they must deserve the same degree of blame.
In summary, our commonsense ideas about moral responsibility imply the contradiction that Killer and Merely Reckless do and do not deserve the same amount of resentment and indignation. More generally, our commonsense ideas about moral responsibility have the paradoxical implication that luck in results can and cannot affect how much praise and blame a person deserves.
Nevertheless, the vexation runs deeper. Luck clearly affects the results of actions but, less obviously, as I’ll demonstrate, luck can also affect actions themselves.
More here.