The way in which we characterize the structural and functional differences between psychopath and normal brains – either as biological disorders or as mere biological differences – can influence our judgments about psychopaths’ responsibility for criminal misconduct. However, Marga Reimer (Neuroethics 1(2):14, 2008) points out that whether our characterization of these differences should be allowed to affect our judgments in this manner “is a difficult and important question that really needs to be addressed before policies regarding responsibility... can be implemented (...) with any confidence”. This paper is an attempt to address Reimer’s difficult and important question; I argue that irrespective of which of these two characterizations is chosen, our judgments about psychopaths’ responsibility should not be affected, because responsibility hinges not on whether a particular difference is (referred to as) a disorder or not, but on how that difference affects the mental capacities required for moral agency. (shrink)