The principle of ‘common but differentiated responsibilities’ forms the core of international environmental law. Whilst it has been the object of vehement debate due to its endorsing of asymmetrical commitments among states, it seems that both in terms of bindingness, as well as content, the principle acts as an effective policy against climate change, reaching a realistic balance between the interests and historical realities of the North and the South. Vasiliki Poula tells us more. 

The principle enshrined in Article 3(1) of the 1992 UNFCCC stipulates one of the foundational rules of international environmental law – that of ‘common but differentiated responsibilities and respective capabilities’. While the principle has been the object of vehement debate, it seems that both in terms of bindingness, as well as content, the principle acts as an effective policy against climate change, reaching a good balance between the interests of the North and the South.

The legal status of the principle – is it binding enough?

The legal effectiveness of the principle in question has been debated. On the one hand, the realism and pragmatism of similar principles of international environmental law are criticised as doing too little, and the force of the generalities of a global moral authority is doubted. On the other hand, the fact that most industrialized countries opposed the inclusion of Article 3 in the FCCC as it could potentially do too much, by attribution binding potential to the FCCC obligations, shows the true gravitas of the principle. However, in fear of the latter, the US introduced amendments to Article 3 – for instance, a chapeau was added, making clear that firstly, the principles were guiding rather than prescriptive and secondly, that parties might consider other principles except for those included in Article 3 by adding ‘inter alia’. Furthermore, the term ‘principle’ (an indication of high level of legal authority) was stricken out by the US and was only kept in the Article’s title, with the added footnote that it existed ‘solely to assist the reader’. These edits intended to deter the Article from reaching the binding status of customary international law. Thus, could it be argued that the principle is not really a legal ‘principle’ as its language is guiding rather than prescriptive?

Despite its weak formal legal status, the effectiveness of the principle should not be dismissed. Its vision is reflected in two operational paragraphs in the FCCC (Article 3 and Article 7), in Principle 23 of the Stockholm Declaration, in the Paris Agreement and in the Preamble to the Kyoto Protocol. As such, the principle acquires sufficient legal gravitas to inform the interpretation of existing obligations and the formation of future duties. Therefore, the enforceability of the principle seems to offer a satisfactory basis for the protection of the environment.

The content of the principle – does it strike a good balance between the common objective of environmentalism and the particular interests of the North and the South?

The principle of common but differentiated responsibility endorses the asymmetrical commitments of different states to ensure universal participation and effective implementation – as a ‘lowest common denominator’ solution. As such, the content of the principle reconciles the environmentalist agenda with intra-generational equity, which is particularly relevant in the South-North context of decolonization. This aim is welcome, since as the Preamble of the FCCC indicates the adverse effects of climate change are of common concern to mankind. As such, the Principle signals a shift beyond outdated formal conceptualizations of formal equality. This reconceptualization of economic and social relations shows that the principle reflects the multidisciplinary nature of the phenomenon of climate change, and indeed, on the basis of effective cooperation, rather than coercive enforcement.

Nevertheless, there is the argument that the principle should entail lower commitment on the part of the developed countries. Firstly, there is the risk of disincentivizing the least developed countries, since their lower developmental rate grants them certain perks – at least in the context of environmental law. In this vein, arguments of ‘historical responsibility’ and ‘compensation for past deeds’ are viewed as clichés in an effort to deter attributing to the South a ‘free rider’ status, hindering the sacrifices of the North. Furthermore, there is the risk of the distinction between developed and developing countries becoming outdated – after all, income levels of states are constantly evolving.

Secondly, the absence of binding commitments for developing countries might discourage developed countries and make them feel as if they are making a disproportionate sacrifice. For instance, when the US did not ratify the Kyoto Protocol, the minimal commitments of the developing countries were cited as one of the key justifications.  It is perhaps on this basis that a trend towards symmetry is appearing, e.g. in the form of obligations for ‘all Parties’ under the 2015 Paris Agreement. Furthermore, the 2019 Report on Climate Change and Poverty has noted that while states are called to provide assistance to developing countries, the issue of differentiated responsibilities is avoided.

However, those fears are not tenable and should not undermine the principle, mainly due to the Kyoto Protocol, which elucidates the UNFCCC and ensures that all parties work towards the desired aim of sustainable development, according to their individual needs and capacities – after all, this is what renders the principle a product of substantial justice. Developing countries (non-Annex I) must develop in a sustainable manner and prepare for climate change’s effects, while developed countries (Annex II) must pledge to mitigate their emissions according to specific targets and timelines. The Clean Development Mechanism fosters cooperation, by allowing developing nations to invest in sustainable projects in developed countries.

Furthermore, the colonial context of the problem vindicates this asymmetry due to the gigantic ecological debt that the South is owed by the North. The principle offers a pragmatic acceptance of the North-South division and the colonial heritage, both in terms of responsibilities (by implicitly acknowledging that since the North has had a disproportionate share of benefits, burdening the environment, while at the same time taking advantage of the South or deterring it from properly develop, it shall also shoulder the cost of environmental protection) and capabilities (due to the asymmetrical disposition of financial, scientific and technological resources).

The question of whether the principle goes far enough to rectify historical wrongs also needs to be addressed – i.e. the question of whether the Principle should entail more. One could be worried about an unspoken assumption that the Third World is treated as a ‘grudging participant’ in the environmental problem. For instance, Principle 7 of the Rio Declaration, invokes cooperation on the basis of ‘global partnership’ rather than out of a sense of duty towards the South. Coupled with the US’s interpretative statement acknowledging the leadership role of developed countries – without, however, having any binding obligations –, concerns arise over the extent to which the principle achieves global cooperation or if instead, it perpetuates the South’s developmental state and its dependence on the North’s investments. Furthermore, it shall be noted that most developing countries are likely to be more affected by climate change according to the 1995 IPCC Report, while the 2019 Report on Climate Change and Poverty expresses particular concern for the negative impacts in developing countries and for people living in poverty, who are noticeably invisible, despite being the prime victims of climate change, raising human rights questions, too.

Nevertheless, we find the thesis presenting the international community as unable to accommodate for the historical injustice blinkered. We believe that the principle’s language is conceptualized in such a way that it represents the interests of both the South and the North, without showing that the South is forcefully integrated in the framework of international environmental law. The North and the South inhabit different historical realities and embrace different truths– but since, we have to protect the same planet, those differences need to be reconciled in a fruitful way: not by dismissing the South’s concerns, but also by making sure that the North is willing to participate. Given the urgent nature of the environmental crisis, it is better to bend than to break. Otherwise, the North’s inhibitions (as when the US did not ratify the Kyoto Protocol) will multiply and unfortunately, once again, the price will be paid by the South.


Vasiliki Poula (@VasilikiPoula) is a Law student at the London School of Economics, and a research assistant at the Hellenic Foundation for European & Foreign Policy.

The views expressed in this post are those of the author and in no way reflect those of the International Development LSE blog or the London School of Economics and Political Science.