Rational Choice or Deliberation? Customary International Law between Coordination and Constitutionalization

Rational-choice approaches have gained in prominence in recent years. However, by focusing on behavioral equilibria, they can only explain phenomena of traditional customary law, which is mainly identified by an analysis of state practice. International legal scholarship increasingly reverts to interpretative methods of identifying unwritten norms, though – e.g., in the fields of human rights and global public goods. This contribution analyzes whether such approaches are just idealist pipe dreams or whether the concerned principles have legal normativity. It offers a constructivist explanation and claims that limiting one's focus to the aspect of norm compliance neglects the dynamic dimension of law.