Despite its moral immediacy, there are serious theoretical objections, best described as "realist," to an expansive conception of judicial open-mindedness. Almost invariably, the normative basis of judicial impartiality is traced to what is described as "natural justice"; specifically the celebrated maxims of nemo iudex in causa sua and audi alteram partem. But the relationship of this moral bedrock to the exigencies and settled practices of constitutional adjudication is far from straightforward. In Part I, the article proceeds with a doctrinal analysis of the legality of Justice Antonin Scalia's decision to sit in the case of Hamdan v. Rumsfeld notwithstanding his prior comments on legal questions ostensibly related to its subject matter. Taking a broader perspective, Part II considers whether objections to Justice Scalia's participation in Hamdan can be reconciled with the nature of appellate adjudication and, in relation to dissenting opinions, with an established feature of adjudicative practice in most common law jurisdictions.