By Lenz, Tobias, and Alexandr Burilkov
What drives processes of institution building in regional international organizations (RIOs)? We challenge established theories of regionalism, and of institutionalized cooperation more broadly, that treat different organizations as independent phenomena whose evolution is conditioned primarily by internal causal factors. Developing the basic premise of diffusion theory, that decision making is interdependent across organizations, we argue that institutional pioneers, specifically the European Union, shape regional institution building processes in discernible ways. We hypothesize two pathways of EU influence – active and passive – and stipulate an endogenous capacity for institutional change as a key scope condition for their operation. Drawing on a new and original dataset on the institutional design of 34 RIOs in the period from 1950 to 2010, the paper finds that (1) both the intensity of an RIO’s structured interaction with the EU (active influence) and the EU’s own level of delegation (passive influence) are associated with higher levels of delegation in other RIOs, (2) passive EU influence exerts a larger overall substantive effect than active EU influence and (3) these effects are strongest in RIOs based upon founding contracts that contain open-ended commitments. These findings indicate that the creation and subsequent institutional evolution of the EU has made a difference to the evolution of institutions in other RIOs, thereby suggesting that existing theories of regionalism are insufficient to account for processes of institution building in RIOs.