Conventions pervasively shape and constrain executive discretion and are an indispensable tool for understanding the issues discussed in the articles. Debates among legal academics over executive discretion misfire if and when the role of conventions is overlooked or misunderstood. In particular, legal debates over executive discretion should take account of three distinctions: (1) between contingent politics and conventions; (2) between intragovernmental conventions and extragovernmental conventions; and (3) between conventions against doing things and conventions against saying things. The last distinction, in particular, illuminates the strong resistance, in contexts such as immigration, to executive policy statements that make explicit a pattern of enforcement
discretion, one that would otherwise remain implicit. Even holding legal authority constant, making that authority explicit through general policy statements may trigger the normatively inflected political sanctions that are characteristic of conventions.