The Problem of Shared Irresponsibility in International Climate Law

States have treaty-based and customary international law-based responsibilities to ensure that greenhouse gas emissions emanating from their territory do not cause transboundary harm. However, those international legal responsibilities conflict with the observed behavior of states, which suggests a general rule of irresponsible treatment of the global commons. This paper, written for a conference (and eventual book) on shared responsibility in international law, examines that conflict and two potential mechanisms for resolving it: (1) international litigation and (2) various types of polycentric approaches to climate governance. Several international legal scholars have been advocating litigation as a means of compensating victims and creating incentives to mitigate emissions and negotiate more forceful international agreements. But they are like lawyers in search of clients. To date, no climate cases have been brought before the International Court of Justice (or any other international tribunal). The reason is that obstacles to successful international litigation are even more formidable than those that have caused all domestic (US) climate-related tort claims to fail. Even if international climate litigation could be successful, it could well have perverse impacts on international climate (and other) negotiations. Instead of inculcating shared responsibility, states might become more reluctant to enter into international agreements in the first place. Contrary to the facile notion that global problems require global solutions, this paper suggests that shared responsibility for greenhouse gas mitigation is likely to be spurred by linkable actions taken at national and sub-national levels. This argument is supported by an emerging literature on polycentric climate governance using various (compatible, rather than mutually-exclusive) approaches, including regime complexes, building blocks, and tipping sets