Sustainable Development From The Perspective Of International Law

It requires accommodation, reconciliation and integration between economic growth, social justice, and environmental protection

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The Foundation for International Environmental Law and Development (an independent NGO comprising public international lawyers) defines sustainable development as “…a legal term which refers to the processes, principles and objectives, as well as to a large body of international agreements on environmental, economic and civil and political rights.”

According to the Centre for International Sustainable Development Law (CISDL), the concept of sustainable development, in international law, requires accommodation, reconciliation and integration between economic growth, social justice (including human rights) and environmental protection objectives, towards participatory improvement in collective quality of life for the benefit of both present and future generations. The term ‘sustainable development law’ describes an emerging corpus of international legal principles and instruments which address the intersections between international economic, environmental and social law (including human rights law), towards development that can last for the benefit of present and future generations.

Sustainable development can thus be seen as “a broad umbrella” within which specialised fields of international law promoting economic development, environmental protection and respect for civil and political rights rest. This consists of principles, rules or institutional arrangements that the international community (states, international institutions and non-governmental actors) has endorsed.

Specifically, the International Court of Justice (ICJ) in adjudicating a dispute between Hungary and Slovakia in the Gabeikovo-Nagymaros Project case, invoked the ‘concept of sustainable development’ to suggest a way forward:

“Throughout the ages, mankind has, for economic and other reasons, constantly interfered with nature. In the past this was often done without consideration of the effects upon the environment. Owing to new scientific insights and to a growing awareness of the risks for mankind — for present and future generations — of pursuit of such interventions at an unconsidered and unabated pace, new norms and standards have been developed, set forth in a great number of instruments during the last two decades. Such new norms have to be taken into consideration, and such new standards given proper weight, not only when States contemplate new activities, but also when continuing with activities begun in the past. This need to reconcile economic development with protection of the environment is aptly expressed in the concept of sustainable development.”

The dispute concerned a 1977 Treaty between Czechoslovakia and Hungary over the building of two barrages on the Danube river, to be jointly operated. Work on the project was suspended as Hungary raised environmental concerns. This led Czechoslovakia to impose a unilateral solution by diverting 80% of the water to Slovak territory. By then, Czechoslovakia had split into two countries with Slovakia assuming responsibility over the project. Hungary then purportedly terminated the Treaty. In April 1993, the dispute was referred to the ICJ.

The ICJ decided that one barrage instead of two to be jointly operated was the appropriate solution. One of the justifications given by the Court was the need to ensure ‘sustainable development’ such that the environmental effects of the operation of the Gabeikovo power plant had to be taken into consideration. In so doing, the Court was effectively saying that development “does not exist in the absolute sense, but is relative always to its tolerance by the environment”. In its decision, the Court, through the opinion of Judge Weeramantry, notes that the concept of sustainable development is an important part of modern international law.

Beyond the ICJ, the WTO Appellate Body recognised this concept in considering the US Shrimp ban on other countries that did not use Turtle Excluder Devices when harvesting for shrimp (the Shrimp-Turtle case). It held that the US measures were ‘provisionally justified’ as it was concerned with the conservation of exhaustible natural resources. However, this was subject to a procedural element in that the US had to go through the appropriate diplomatic means such as relevant multilateral agreements before imposing unilateral measures such as the aforesaid ban.

Despite the recognition of both the ICJ and the WTO, it remains to be seen the status of sustainable development in international law. Is it a custom or convention? Does it have both substantive and procedural consequences? Philippe Sands, in his article ‘International Courts and the Application of the Concept of ‘Sustainable Development’’ concludes:

“One can therefore expect ‘sustainable development’ to be relied upon in other fora, perhaps to justify the integration of environmental considerations into foreign investment protection agreements (for example in the context of ICSID proceedings) or the integration of developmental considerations into the application of human rights norms.”

Since the 1997 Gabčíkovo-Nagymaros Project (Hungary v Slovakia) case, the ICJ has had other opportunities to consider the concept of sustainable development. In the Pulp Mills on the River Uruguay case, the ICJ did not invoke the term ‘sustainable development’, but referred to its 1997 judgement in Gabčíkovo-Nagymaros Project and to its Advisory Opinion on the Legality of the Threat or Use of Nuclear Weapons to reiterate the international obligation to protect and respect the environment.

Separately, the Permanent Court of Arbitration has referred to the “notion of sustainable development” in balancing the interests of Belgium and the Netherlands in the May 2005 Arbitration Regarding the Iron Rhine (“Ijzeren Rijn”) Railway (Belgium v. Netherlands) case. In deciding that Belgium had the right to reactivate the Iron Rhine Railway, which was opposed by Netherlands on environmental grounds, the Tribunal held at para 59 of its Judgement that

“[e]nvironmental law and the law on development stand not as alternatives but as mutually reinforcing, integral concepts, which require that where development may cause significant harm to the environment, there is a duty to prevent, or at least mitigate such harm. … This duty, in the opinion of the Tribunal, has now become a principle of general international law. This principle applies not only in autonomous activities but also in activities undertaken in implementation of specific treaties between the Parties.”

Thus, sustainable development steps in as a guiding ‘principle’ where economic development and environmental challenges intersect. The Tribunal thus ordered that costs of activating the railway including costs of environmental protection measures be shared between both parties.

The CISDL in its concept paper states that sustainable development is also an object and purpose of many international treaties. This includes the:

  • 1992 UN Convention on Biological Diversity and its 2000 Cartagena Protocol

  • 1992 UN Framework Convention on Climate Change and its 1997 Kyoto Protocol

  • 1994 UN Convention to Combat Desertification and Drought

  • 1994 North American Free Trade Agreement

  • 1995 Straddling Fish Stocks Agreement

  • 2000 Cotonou Partnership Agreement

  • 2001 International Treaty on Plant Genetic Resources for Food and Agriculture

The 2002 Convention for Cooperation in the Protection and Sustainable Development of the Marine and Coastal Environment of the Northeast Pacific goes further to provide a definition at article 3(1)(a):

“…[S]ustainable development means the process of progressive change in the quality of life of human beings, which places them as the centre and primary subjects of development, by means of economic growth with social equity and transformation of production methods and consumption patterns, sustained by the ecological balance and life support systems of the region. This process implies respect for regional, national and local ethnic and cultural diversity, and full public participation, peaceful coexistence in harmony with nature, without prejudice to and ensuring the quality of life of future generations.”

Today, we have the Sustainable Development Goals and the 2030 Agenda for Sustainable Development. Indeed it would not be presumptuous to say that Sustainable Development as an international movement has evolved and gained momentum in the last 15 years. Nevertheless, its role in international law remains uncertain — does it have the currency of an international rule of law, norm, or something else?

Virginie Barral calls it an “unavoidable paradigm”. While undoubtedly a powerful tool for judges in the interpretation of existing norms, its real value lies as in its obligatory function — whether through treaties or otherwise — for states to implement and enforce thus ensuring sustainable development in the world. Another point to note is the evolutive nature of sustainable development. This means that it will vary in time, area or subjects concerned (ratione temporis, loci, personae, materiae) and the obligations will depend on whether it is a developed or developing country. For example, the 1992 Framework Convention on Climate Change (UNFCCC) fully endorses the principle of common but differentiated responsibilities.

In international law, sustainable development seems to have achieved in a short period of time a status equivalent to an international norm. Not only does it set an objective for states to achieve but also regulates their conduct and serves an important hermeneutical function in the interpretation of treaties as well as in circumstances when environmental, economic and social considerations and related legal norms come into conflict e.g. in the Shrimp Turtle case.