Reaching for the Threshold: How Minimum Participation Rules Facilitate Multilateral Treaty Ratification

Abstract

Uncertainty about other states’ willingness to cooperate often impedes collective action. Many multilateral agreements address this by incorporating Minimum Participation Rules (MPRs), which are provision-point mechanisms that specify the minimum coalition size required for a treaty to enter into force. Public and institutional choice theories suggest that such mechanisms lower barriers to participation by reducing coordination problems and limiting opportunities for freeriding. To test this assumption, we introduce a survival estimator to evaluate how the inclusion and design of MPRs impact treaty ratification across diverse issue areas. Drawing on data from agreements deposited with the United Nations Secretary-General, this study offers the first systematic analysis of MPRs in multilateral treaty cooperation. We find that threshold provisions accelerate ratification, even in contexts where incentives to freeride are unlikely to be significant.