The Architecture of External Normative Structures: Reconstructing Bulygin’s Theory of Applicability

This article revisits Eugenio Bulygin’s theory of membership and applicability in order to address a familiar paradox of legal continuity: courts are sometimes under a legal duty to apply norms that no longer belong to the presently valid legal system. Building on Bulygin’s distinction between membership in a momentary system and applicability in adjudication, as well as his analysis of internal and external legal time, the article develops a structural account of applicability in terms of external two-element structures ⟨Na, No⟩. These are ordered pairs in which an application norm (Na) selects and activates an object norm (No) as the standard for a given domain of cases. This external-structural perspective dissolves the apparent tension between derogation and legal continuity without resorting to the “post-derogation validity” of repealed norms. Intertemporal directives such as lex mitior are reconceived as present application norms that establish couplings between current adjudication and past legislation. The article then uses this framework to diagnose three structural pathologies of legal systems: severed couplings (where the bridge from adjudication to an object norm is missing), inconsistent couplings (where competing application norms collide), and parasitic couplings (where procedural or jurisdictional metanorms structurally nullify the effective domain of otherwise valid rights). By distinguishing analytically between the structural fact of nullification (Deff ≈ ∅) and the political diagnosis of abusive formalism and autocratic legalism, the article shows how logical models of normative systems can illuminate institutional drift and the indirect erosion of rights. The concluding sections outline a research programme for reconstructing doctrinal fields and analysing constitutional backsliding in terms of the dynamics of external two-element structures.