We propose causal agency models for representing and reason-ing about ethical dilemmas. We find that ethical dilemmas, al-though they appear similar on the surface, differ in their formalstructure. Based on their structural properties, as identified bythe causal agency models, we cluster a set of dilemmas in Type1 and Type 2 dilemmas. We observe that for Type 1 dilemmasbut not for Type 2 dilemmas a utilitarian action does not domi-nate the possibility of refraining from action thereby constitut-ing a conflict. Hence, we hypothesize, based on the model, thatType 1 dilemmas are perceived as more difficult than Type 2dilemmas by human reasoners. A behavioral study where par-ticipants rated the difficulty of dilemmas supports the models’predictions.