IN international law, the concept of “erga omnes” (Latin for “in relation to everyone”) obligations refers to specifically determined obligations that states have towards the international community as a whole. The concept has its origins dating as far back as Roman law and is used to describe obligations or rights to all.

The concept was invoked in the famous “obiter dictum” (Latin for ‘something said in passing”) of the judgment of the International Court of Justice (ICJ) in the Barcelona Traction case where it was said that erga omnes obligations referred to the “obligations of a State towards the international community as a whole”, that is, obligations that “by their very nature … are the concern of all States”. (See Barcelona Traction, Light and Power Company Limited ICJ Reports 1970, para. 33)

The ICJ thus identified the notion of obligations existing towards the international community as a whole with that of obligations existing towards all States. The court said:

“In view of the importance of the rights involved, all States can be held to have a legal interest in their protection; they are obligations erga omnes.”

Some 35 years later, the concept was adopted in a 2005 resolution of the Institute of International Law entitled “Obligations erga omnes in international law”. Article 1(a) defines an obligation erga omnes as “an obligation under general international law that a State owes in any given case to the international community, in view of its common values and its concern for compliance, so that a breach of that obligation enables all States to take action”.

Article 1(b), on the other hand, defines an obligation “erga omnes partes” as “an obligation under a multilateral treaty that a State party to the treaty owes in any given case to all the other States parties to the same treaty, in view of their common values and concern for compliance, so that a breach of that obligation enables all these States to take action”.

What is significant from the above is the confirmation of the existence of the erga omnes obligations in international law, which must include the general obligation of states to protect the atmosphere or environment. This in turn includes the obligation to prevent transboundary air pollution of a bilateral or regional nature.

States must take heed of the advisory opinion of the ICJ in the advisory proceedings on the Legality of the Threat or Use of Nuclear Weapons, where it was examined whether the use of nuclear weapons would lead to damage to the environment, presumably including the global atmospheric environment.

In its advisory opinion, the court recognised that “the environment is under daily threat and that the use of nuclear weapons could constitute a catastrophe for the environment (and) that the environment is not an abstraction but represents the living space, the quality of life and the very health of human beings, including generations unborn.”

The court accordingly pronounced that the “existence of the general obligation of States to ensure that activities within their jurisdiction and control respect the environment of other States or of areas beyond national control is now part of the corpus of international law relating to the environment.” (See Legality of the Threat or Use of Nuclear Weapons, Advisory Opinion, ICJ Reports 1996, p. 226, at p. 241. The UN general assembly had asked for the advisory opinion.)

Read and taken together with another international law principle of “sic utere tuo ut alienum non laedas” (Latin for “use your own property so as not to injure that of another”) it will come to this: under the principles of international law, no state has the right to use its territory in such a manner as to cause injury in or to the territory of another or the properties or persons therein.

In short, states have obligations to respect and protect the natural environment.

The ICJ may not have clarified in full detail the extent of the obligations, but the principle that damage must not be caused to other nations is a fundamental principle of modern environmental law, which is well entrenched in international law. It is a “deeply entrenched principle, grounded in common sense, case law, international conventions, and customary international law”. Judge Weeramantry in the Nuclear Tests (New Zealand v France) Case (“Nuclear Tests II”), ICJ Reports 1995, p. 288, at p. 306, para. 64)

Given the cases before the ICJ, Shinya Murase, the UN special rapporteur on protection of the atmosphere has argued that the court has confirmed the principle not to cause significant harm to the atmospheric environment of other states as an established principle of customary international law. by argues that the cases before (See The Second Report on the Protection of the Atmosphere, Document A/CN4/681, 2015 p. 209)

A more recent statement on states’ obligation to protect the atmosphere can be seen in the draft guidelines on the protection of the atmosphere 2021, which was adopted by the UN International Law Commission at its 72nd session in 2021, and submitted to the UN General Assembly as a part of the Commission’s report covering the work of that session (A/76/10, para. 39).  Guideline 3 on “Obligation to protect the atmosphere” states as follows:

“States have the obligation to protect the atmosphere by exercising due diligence in taking appropriate measures, in accordance with applicable rules of international law, to prevent, reduce or control atmospheric pollution and atmospheric degradation.”

If Asean member states were guided by the above obligation, there would not be regional transboundary haze. – October 6, 2023.

* Hafiz Hassan reads The Malaysian Insight.

* This is the opinion of the writer or publication and does not necessarily represent the views of The Malaysian Insight. Article may be edited for brevity and clarity.