Description: Department Seminar

Location: 368A Heady Hall

Contact: Bertan Turhan

Title: Contesting an International Environmental Agreement

Abstract: International Environmental Agreements (IEAs) rarely require unanimous ratification. Instead, they include a minimum ratification threshold (MRT)—the smallest number of signatories needed for the treaty to enter into force. MRTs matter because ratification is uncertain within each country, often due to political and economic incentives to free ride. We develop a parallel contest model of IEA formation in which countries jointly set both the MRT and the emissions target. Within each country, pro- and anti-IEA groups lobby the government over ratification, and their success depends on lobbying resources and pivotality in the global ratification process. Our analysis shows: (1) The optimal MRT and emissions target are chosen so that, in expectation, each country’s ratification decision is pivotal to the agreement passing; (2) Stricter emissions targets reduce the probability of ratification because anti-IEA groups respond more strongly than pro-IEA groups; and (3) Higher MRTs can increase ratification probability by raising the strategic value of participation. The model bridges domestic political economy and international treaty design, offering new insights into how MRTs and emission targets interact.