Third States, Breach and Changed Circumstances

Peremptory norms

Article 53 provides that a treaty is void if, at the time of its conclusion, it conflicts with a peremptory norm of general international law, a norm accepted and recognised by the international community of States as a whole as one from which no derogation is permitted. Such a norm is called jus cogens.

No environmental rule has been authoritatively held to be jus cogens. Candidates have been argued, most often the prohibition of massive environmental destruction, but no tribunal has decided it. A student should say exactly that rather than overclaim.

The three exits

Article 60: material breach. A material breach is a repudiation not sanctioned by the Convention, or the violation of a provision essential to the accomplishment of the object or purpose. For a bilateral treaty the innocent party may terminate or suspend. For a multilateral treaty the other parties, acting together, may suspend or terminate as between all of them or as against the defaulting State. Paragraph 5 excludes provisions relating to the protection of the human person in humanitarian treaties.

Article 61: supervening impossibility. Permanent disappearance or destruction of an object indispensable to performance. Temporary impossibility permits only suspension. Paragraph 2 bars the plea to a party whose own breach caused the impossibility.

Article 62: fundamental change of circumstances. The Latin tag is rebus sic stantibus. The change must not have been foreseen; the circumstances must have constituted an essential basis of consent; and the change must radically transform the extent of obligations still to be performed. It does not apply to a treaty establishing a boundary.

The case that shows how narrow they are

Hungary argued all three, and lost on all three.

Facts. Gabcikovo-Nagymaros Project (Hungary/Slovakia), ICJ Reports 1997, p. 7. Hungary and Czechoslovakia agreed by treaty in 1977 to build a system of barrages on the Danube. In 1989 Hungary suspended and then abandoned its works, pleading ecological necessity. Czechoslovakia diverted the river on its own territory, a scheme called Variant C, and put it into operation in October 1992. Hungary then purported to terminate the treaty.

Held. Both parties had committed internationally wrongful acts. Hungary was not entitled to suspend and abandon its works. Czechoslovakia was entitled to proceed to Variant C but not to put it into operation unilaterally. Hungary's notification of termination did not terminate the 1977 treaty, which remained in force. On the environment, the Court said that newly developed norms of environmental law are relevant to implementation of the treaty, that in the field of environmental protection vigilance and prevention are required on account of the often irreversible character of damage to the environment and of the limitations inherent in the very mechanism of reparation of this type of damage, and that the need to reconcile economic development with protection of the environment is expressed in the concept of sustainable development.

Why it matters here. It is the standing authority that an environmental objection to a treaty, however genuine, is not by itself a ground for walking away from it. The remedy is to renegotiate performance in the light of current standards, which is what the Court ordered.

Worked example

State X has ratified a regional convention prohibiting the import of hazardous waste. State Y, which is not a party, ships waste to a third State that is a party. State X then wishes to leave the convention, saying the price of compliance has become intolerable. Take the two questions in turn.

Question one: is State Y bound?

1. Start with the rule. A treaty does not create either obligations or rights for a third State without its consent. That is the pacta tertiis rule in article 34 of the Vienna Convention on the Law of Treaties 1969.
2. Check the two exceptions. Article 35: an obligation arises for a third State only if the parties intend the provision to establish it and the third State expressly accepts it in writing. Article 36: a right arises if the parties so intend and the third State assents, and its assent is presumed so long as the contrary is not indicated. The asymmetry is deliberate. Obligations need express written acceptance; benefits are presumed accepted.
3. Check the real exception. Article 38. Nothing in articles 34 to 37 precludes a rule set forth in a treaty from becoming binding upon a third State as a customary rule of international law, recognised as such. This is the door through which the substance of environmental treaties reaches non-parties, and it is why the customary status of the duty of prevention matters so much in this paper.
4. Answer. State Y is not bound by the convention. It may be bound by any rule in it that has become customary, and it is bound by the customary duty of prevention. It is not bound by the convention's procedures.

Question two: may State X leave?

1. Look first at the treaty itself. Most of the instruments in this book contain a withdrawal clause, typically permitting withdrawal after three years with one year's notice. If there is one, use it, and the general law does not arise.
2. If there is none, consider material breach. Article 60. A material breach is a repudiation of the treaty not sanctioned by the Convention, or the violation of a provision essential to the accomplishment of the object or purpose of the treaty. It entitles the other parties, by unanimous agreement, to suspend or terminate, or a specially affected party to suspend as between itself and the defaulting State. Note article 60(2)(c), the provision for treaties of such a character that a material breach by one party radically changes the position of every party.
3. Consider supervening impossibility. Article 61. Impossibility resulting from the permanent disappearance or destruction of an object indispensable for the execution of the treaty. Temporary impossibility grounds only suspension, and a party may not invoke it if the impossibility results from its own breach.
4. Consider fundamental change of circumstances. Article 62. It may not be invoked unless the existence of the circumstances constituted an essential basis of the consent of the parties, and the effect of the change is radically to transform the extent of obligations still to be performed. The two conditions are cumulative and the article is drafted in the negative, which is itself a signal about how it is to be applied.
5. Test State X's argument. Cost is not impossibility, and an increase in the burden of performance is precisely what article 62 was drafted to exclude. In the Gabcikovo-Nagymaros case the Court rejected every ground of termination advanced, holding that the changes relied on were not so profound as to radically transform the extent of the obligations still to be performed, and that a state of ecological necessity, even if established, would not terminate a treaty but only suspend the wrongfulness of the conduct while the necessity lasted.
6. Answer. State X must use the treaty's own withdrawal clause. If there is none, it stays, because the general law's exits are narrower than it hopes.

The two questions together are the whole chapter. A treaty cannot reach outward except through custom, and a party cannot get out except through the door the treaty itself provides.

Quick revision

• Articles 34 to 38: no obligations or rights for third States without consent, but a treaty rule may bind them as custom.
• Article 53: a treaty conflicting with jus cogens is void. No environmental norm has been authoritatively held to be jus cogens.
• Article 60: material breach, meaning repudiation or violation of an essential provision.
• Article 61: supervening impossibility, permanent destruction of an indispensable object.
• Article 62: fundamental change of circumstances, unforeseen, essential to consent, radically transforming the obligations.

Test yourself

1. How can a rule in a convention bind a State that never joined it? Only if the rule also exists as customary international law. Article 38 of the Vienna Convention preserves that possibility; Article 34 excludes any other route.

2. Hungary said the works would ruin the Danube. Why did that not release it from the 1977 treaty? Because none of Articles 60 to 62 was satisfied, and because a state of necessity to which a party has itself contributed cannot be invoked. The Court kept the treaty alive and required the parties to perform it in the light of current environmental standards.

3. Is any environmental rule jus cogens? None has been authoritatively so held. Say that, and name the argument rather than the conclusion.