The Pure Theory of Law which saw law as a "Norm of Action" was advocated by:

Hans Kelsen, an Austrian jurist and legal philosopher, propounded the "Pure Theory of Law", which conceives of law as a hierarchy of normative "ought" propositions (norms of action) deriving their validity from a presupposed basic norm (Grundnorm), purified of political, sociological, and moral elements. A. V. Dicey is famous for his exposition of the Rule of Law and Parliamentary Sovereignty in British constitutional law, Leon Duguit developed the theory of social solidarity (droit objectif), and Francois Geny advocated free scientific research (libre recherche scientifique) in legal interpretation.