Enlargement processes and distributional conflicts: The politics of discriminatory membership in the European Union

This paper examines discriminatory membership in the European Union from a game-theoretical perspective. I argue that discriminatory membership enables the enlargement of international organizations with heterogenous member states. EU members impose discriminatory measures on new members to redistribute enlargement gains from new members to particularly negatively affected EU members as to render expansion pareto-efficient. The empirical findings of a probit analysis on the EU accession negotiations and outcomes of all five EU enlargement rounds support the theoretical claim. The EU grants acceding states restricted membership rights if distributional conflicts emerge. Moreover, the candidate's bargaining power and the possibility of alternative compensation schemes influence the enlargement outcomes.