Reinterpreting constitutional amendment procedures through political philosophies

Research on constitutional amendment procedures has primarily focused on the policy outcomes produced by constitutional amendments or on the effects of amendment rules on constitutional rigidity. This article examines constitutional amendment procedures as value-expressive institutional designs. Building on a classification of amendment procedures, the article employs ideal types drawn from political philosophy as analytical tools. It argues that specific configurations of constitutional amendment procedures can be interpreted as expressing values characteristic of liberalism, republicanism, and populism. Liberal-oriented procedures emphasise the protection of fundamental rights through counter-majoritarian constraints, judicial veto players, and unamendability clauses. Republican-oriented procedures prioritise deliberation, temporal safeguards, and consensus-building mechanisms aimed at reducing arbitrariness in constitutional change. Populist-oriented procedures privilege the direct and unmediated expression of popular sovereignty, often minimising institutional filters and deliberative constraints. The article argues that the constructed typology may serve as an analytical tool for assessing the ideological character of constitutional systems through the political-philosophical assumptions embedded in their amendment procedures. To do so, it proposes a two-step constitutional amendment congruence test to analyze the underlying political philosophy within the amendment procedure and to assess whether constitutional practice and informal or unwritten elements mediate or depart from the formal design within informal constitutional change. The higher the congruence, the stronger the analytical value it has to assess the political-philosophical character of the constitution as a whole.