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Unpublished Paper
The New International Law-Makers? Conferences of the Parties to Multilateral Environmental Agreements
ExpressO (2009)
  • Annecoos Wiersema
What do Conferences of the Parties (COPs) to multilateral environmental agreements contribute to international legal obligation? Much of the activity of COPs does not require the consent of every state party to the treaty to come into effect and does not provide for any form of opt-out for dissenting states; nevertheless, COPs frequently pass agreements that alter the application and scope of their treaties. This article discusses the significance of this activity – what I term consensus-based COP activity – for our understanding of the international legal system and its touchstone of state consent. Conventional categories for the sources of international law are inadequate to capture the significance of this activity. It does not fit within the traditional sources of hard international law – treaty and custom. Yet relying by default on the usual classification of this activity as soft law is also inadequate, because it obscures the complex relationship between consensus-based COP activity and the underlying treaty obligations of the parties to that treaty. This article argues that the problem lies in the question we are asking. Instead of asking whether COP activity is really law, we should be asking what the relationship is between COP activity and the original international legal obligations of the parties to the underlying treaty. Reframing the question in this way gives us a new and more accurate picture of the role of consensus-based COP activity in international legal obligation. The picture we get is of a series of resolutions and decisions that, although they do not generally stand apart from the parties’ primary treaty obligations, enrich those original legal obligations by deepening and thickening them. In turn, reframing the question also allows us to explore questions about adaptability, sectoral fragmentation, and accountability in the international legal system.
  • sources of international law,
  • customary international law,
  • treaty law,
  • fragmentation,
  • multilateral environmental agreements,
  • conferences of the parties,
  • Kyoto Protocol on Climate Change,
  • United Nations Framework Convention on Climate Change,
  • Basel Convention on Hazardous Wastes,
  • Ramsar Convention on Wetlands,
  • Convention on International Trade in Endangered Species,
  • Montreal Protocol on Substances that Deplete the Ozone Layer
Publication Date
March 19, 2009
Citation Information
Annecoos Wiersema. "The New International Law-Makers? Conferences of the Parties to Multilateral Environmental Agreements" ExpressO (2009)
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