The survival of the weakest: the echo of the Rio Summit principles in environmental treaties

Abstract

ABSTRACT This article examines the influence of the 1992 United Nations Conference on Environment and Development, known as the Rio Summit, on the design of subsequent international environmental agreements (IEAs). In particular, it investigates the extent to which the principles outlined in the Rio Declaration were integrated into IEAs concluded in the following years. We focus our investigation on three principles: the precautionary principle, common but differentiated responsibilities, and the polluter pays principle. Analyzing a collection of 2,211 IEAs and their 509 amendments, we find that the Rio Summit catalyzed the dissemination of these principles. However, our study also reveals that the Rio Conference was an inflection point, wherein weaker expressions of these principles became more prevalent. Stronger expressions, which were included in some IEAs prior to the Rio Summit, became relatively less common thereafter. We call this evolutionary process the ‘survival of the weakest’.