My areas of specialization are ethics, moral psychology, and social philosophy. Many of my publications began with work on my Ph.D. dissertation about the nature of evil. Others began with work on my postdoctoral research about the notion of collective evil. As a result, many of my publications are about the nature of evil and the notions of shared and collective responsibility. Recently, I have begun work on questions of moral psychology. I am particularly interested in the reasons people perform evil actions or participate in practices that lead to harmful injustices. Besides my work on evil, I have also published in ethics more generally, on topics such as Kantian ethics, consequentialism, and the nature of virtue.