Unwritten Rules: Informal Institutions in Established Democracies

Scholars of the developing world have driven a surge of interest in unwritten or informal institutions as determinants of political outcomes. In advanced industrial democracies, by contrast, informal institutions often remain consigned to the analytic margins. This article makes a case for greater attention to informal political institutions in established democracies, and it introduces a theoretical framework to support such analysis. Informal institutions, understood as the unwritten rules of political life, are seen to perform three functions: they complete or fill gaps in formal institutions, coordinate the operation of overlapping (and perhaps clashing) institutions, and operate parallel to formal institutions in regulating political behavior. These three roles of informal institutions are associated with different characteristic patterns of institutional stability and change. The article illustrates its theoretical framework with case studies from American politics, the subfield in which formal-institutional analysis has flourished most. These cases are the historical norm of a two-term presidency (a completing institution), the unwritten rules of the presidential nomination process (coordinating institutions), the informal practice of obstruction in the Senate (a parallel institution), and the normative expectation that presidents should address the public directly (which performs all three functions).