Much has been written about the fittingness, epistemic, and standing norms that govern blame. In this paper, we argue that there exists a norm of blame that has yet to receive philosophical discussion and without which an account of the ethics of blame will be incomplete: a norm proscribing comparatively arbitrary blame. By reflecting on the objectionableness of comparatively arbitrary blame, we stand to elucidate a substantive, and thus far overlooked, norm governing our attributions of responsibility. Accordingly, our aim in (...) this paper is to develop a comparative non-arbitrariness condition on blame that can enrich our understanding of the ethics of blame. (shrink)