Abstract
In 2021, environmental procedural rights were strengthened in Latin America and the Caribbean when the legally binding Escazu Agreement came into force. This new treaty seeks to implement Principle 10 of the 1992 Rio Declaration, which promotes access to information, participation, and justice in environmental matters. The treaty is empirically and theoretically surprising: it bucks the growing trend of informalization in regional and international cooperation and is more highly legalized than institutional design theory would predict. Applying an interpretivist logic of inquiry and drawing on interviews with twenty-three participants in the negotiations, I argue that this outcome can be explained by an alignment of structural conditions that facilitated an alliance between ambitious state and nonstate actors and enabled their influence throughout negotiations. Applying theories of political opportunities and mobilization structures, I show how a network created by the World Resources Institute influenced the agreement’s design and helped secure a high degree of obligation and precision in Latin America’s first environmental treaty.