More than Informal Institutions? A Typology-Based Analysis of Constitutional Conventions

This article focuses on a longstanding yet undertheorized concept in political science: constitutional conventions. Traditionally distinguished from laws by their lack of legal enforceability, recent scholarship has challenged this dichotomy, suggesting that conventions can acquire characteristics typical for formal legal rules. By integrating constitutional conventions into institutionalist theory, this article addresses two research questions: Are constitutional conventions only informal institutions? How are they related to constitutional texts? To answer these questions, the article proposes two original typologies. The first classifies conventions by their degree of formalization and sanctioning mechanisms, illustrating how they may evolve along a continuum from purely informal to increasingly formal institutions. The second typology reflects the relationship between constitutional conventions and constitutional texts, distinguishing between interpretative, gap-filling, modifying, and contradicting conventions. Using these typologies, the article argues that conventions are neither homogeneous nor purely informal institutions, but rather diverse and dynamic rules placed along the formal–informal continuum. In general, the article highlights political science’s (through institutional theory) distinctive capacity to analyze conventions as evolving elements of constitutional governance.