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Home » CCEEL Blog » Climate COP-28: What is all the hype about, what exactly is it that COPs do in legal terms?

Climate COP-28: What is all the hype about, what exactly is it that COPs do in legal terms?

By Tuula Honkonen, Senior Lecturer of International Law. First published in the 2035Legitimacy blog on 1 December 2023.

In the advent of yet another UN Climate Change Conference, it is relevant to ask what these massive gatherings produce in legal terms. What exactly are the COP decisions that are the main legal outcome of the Conference: How and why are they adopted, are they legally binding on the Parties and if not, do they matter? 

Climate negotiations continue with “mandatory” COP decisions

The international negotiations on the new climate treaty came to an end in 2015 when the Paris Agreement saw daylight. The text of the Agreement was finalized. Nevertheless, the Parties continue negotiating, now on further details and implementation of the Paris Agreement. They do not touch the text of the Agreement, though. Instead, Parties negotiate and adopt Conference of the Parties (COP under the UNFCCC) and Conference of the Parties serving as the meeting of the Parties (CMA under the Paris Agreement) decisions by which they are able to set new rules and guidelines to inform and support the implementation of the original Agreements. This further guidance is actually necessary given that the Paris Agreement text is not detailed enough in itself to allow coherent and consistent implementation by the Parties.

This year, CMA decisions are crucially needed for operationalizing the new Loss and Damage Fund to be established under the Paris Agreement, for setting up a new framework for the Global Goal on Adaptation and for the procedures for establishing the new collective quantified goal on finance by 2025, to name the subjects of perhaps the most highly expected COP/CMA decisions from Dubai.

COP decisions are adopted by consensus (the only option under the global climate change agreements) or by a majority vote by the Parties. Consequently, usually a Party cannot opt out from them – unless the treaty specifies so. This is significant since COP decisions can have very far-reaching consequences, even altering the application and scope of the treaty.

Before proceeding, it is to be noted that COP decisions are not the only tangible outcomes of UN climate conferences; the meetings also typically produce high-level political declarations and commitments of action issued by various actors. None of them are legally binding on the Parties. This post focuses, though, on the legally most relevant outcomes of COPs, the decisions of the Parties.

Are COP decisions binding on the Parties?

COP decisions are commonly considered as not strictly legally binding on the Parties of multilateral environmental agreements (MEAs), although contrary opinions have also been presented. The legal nature of COP decisions is not simple to determine beyond question, and there has been a whole international legal debate around the question of whether MEA COP decisions are to be considered as legally binding sources of law.

Overall, it is important to keep in mind that there are different types of COP decisions under MEAs. Some decisions concern a particular country (in non-compliance cases, for instance) while others, the majority, are of a general nature, directed at all Parties to the agreement. MEAs do not usually specify the legal nature of their COP decisions. Furthermore, COP decisions are often phrased in terms that do not imply legally binding obligations on the Parties. It is also possible for COP decisions to derive legal effects from other sources than legally binding language and an “authorization” given by the mother treaty, namely when the decision could be considered to coincide with customary international law.

“Under the international climate regime, rulemaking by COP/CMA decisions can be described as a state of art of its own.”

Under the international climate regime, rulemaking by COP/CMA decisions can be described as a state of art of its own. Neither of the immediate legal sources of climate COP/CMA decisions, the UNFCCC or the Paris Agreement, grants their COP/CMA general authority to make binding decisions. However, the Paris Agreement actually enables CMA decisions with legally binding effects on several issues. A famous example is the Decision on the adoption of the Paris Agreement (1/CP.21) later replaced by Decision on Further guidance in relation to the mitigation section of decision 1/CP.2 (4.CMA.1), where the words the COP “decides” and Parties “shall” are used, implying legally binding obligations for the Parties. Similarly, some CMA decisions in the so-called Paris Agreement Rulebook, a collection of decisions and other guidance for the practical implementation of the Agreement, largely finalized in 2018, are considered as legally binding on the Parties. However, in the negotiations on the package, the Parties also deliberately left unused some of the authority to adopt legally binding guidance granted in the Paris Agreement. Overall, the normative status of the COP/CMA decisions under the international climate regime varies. This complicates the analysis of the decisions’ legal significance.

Do COP decisions matter, after all?

Irrespective of perspectives on COP decisions’ formal legal nature, Parties to an MEA are free to commit to them on a unilateral basis. This is also what happens in practice: the decisions are often de facto followed and treated as binding on the Parties. However, that does not render the COP decisions legally binding as such. In addition, one needs to consider how the Parties perceive the legal status of the decisions that are taken, whether their practical treatment of them as binding results from an actual belief that they are legally bound to implement them or whether they commit to them because they think that it is an appropriate course of action.

“The key function of COP decisions is that they inform the implementation of the underlying treaty, they “thicken” the original obligations.” 

If, and when, it is concluded that COP decisions are not, as a rule, legally binding on the Parties, what is their purpose and (legal) significance? The key function of COP decisions is that they inform the implementation of the underlying treaty, they “thicken” the original obligations. Importantly, COP decisions would lose their meaning without the underlying treaty. The International Law Commission has acknowledged that COP decisions can play a role in the interpretation of treaties. It is also clear that the decisions taken by the Parties carry significant political weight, even if they would not be strictly legally binding.

In the end, we can ask whether it really matters if COP decisions, or “post-treaty instruments” as they are sometimes labelled, are considered legally binding hard law or less binding soft law. Some commentators have argued that the distinction does not truly matter. And yes, in practical terms, it may not matter that much. However, the legal nature of COP decisions can be an issue for states’ domestic procedures. For the European Union, for instance, the procedure for international negotiations (Art. 218 of the Treaty on the Functioning of the European Union (TFEU)) is different depending on whether the outcome of the negotiations is legally binding or not. The legal nature of COP decisions directly matters also within the treaty regime when assessing Party compliance with the agreement, for instance.

Finally, one could question the legitimacy of COP decisions and their implications on the Parties, given that no state consent is required to be bound (even if not in a strict legal sense) by them and that there are in most cases no “implied powers” in the underlying treaties for binding COP decisions. State consent is, after all, a cornerstone of international law and a crucial legitimizing factor to it. In the case of COP decisions, the chain of state consent is quite long if we consider it to derive from the act of a Party ratifying the treaty in question. Then again, if COPs are perceived as relatively autonomous treaty management organizations, they have basically created legitimacy for themselves.

Photo by Michael Fenton on Unsplash