CYIL vol. 13 (2022)

CYIL 13 ȍ2022Ȏ THE JCPoA AND ITS LEGAL STATUS: IF IT WALKS LIKE A TREATY … Therefore, whilst both the draft articles and the VCLTs limit the definition of a treaty and its constituent elements only for the purposes of the respective instruments, the texts of both, as established above, are the codified version of already crystalised customary international law and as such lead a “dual life” as both treaty provisions and as custom. Consequently, it may well be that the treaty provisions in the VCLTs regarding the definition of a treaty are only for the purposes of the VCLTs, but the existing customary international law which they codify applies universally and thus beyond the VCLTs. Given that one of the parties to the JCPoA has been particularly vocal on the international fora that the “Iran deal” is not a treaty 40 and the fact that customary international law is presently discussed, the possibility of this behaviour constituting said State’s right to be a persistent objector must be addressed. As the doctrine of persistent objector could only be successfully utilised while a particular rule of customary international is still being crystalised as such 41 , some forty odd years after the first codification (not crystallisation) of said rule would certainly prove to be too late. Also, had a particular State tried evoking its right to persistently object to a rule of customary international law at the appropriate time, this could only be done in relation to the rule itself, and not to its application. 42 To illustrate – a State could have persistently objected that the definition and constituent elements of a treaty are as they are, and not that a particular international legal instrument is not a treaty as per customary international law on the basis of said State’s right to persistently object to the legal status of the instrument in question. 3. Elements of a treaty So far it has been established that the definition of a treaty and its constituent elements, as provided for in the VCLTs collectively, are based on already crystallised customary international law and thus apply to all of the eight parties to the JCPoA. Said definition and constituent elements of a treaty are that for a legal instrument to be considered a treaty: i) it must be an international agreement ii) it must be concluded between States, States and IOs or between IOs, iii) said international agreement must be in written form, iv) it must be governed by international law, v) it could be embodied in a single instrument or in two or more related instruments, and vi) its particular designation is irrelevant 43 . An analysis of the six elements and the relationship they have with the JCPoA is to follow. A treaty must be an international agreement Every treaty is an agreement, but not every agreement is a treaty 44 , as evidenced by the need to make reference to both when needed 45 . Literature as well as the travaux preparatoires of the ILC Draft Articles provide no clarification as to the “international” qualifier of the term agreement. Given that two of the elements of a treaty are that it must be governed by international law and concluded between States, which are subjects

40 Letter from Julia Frifield to Mike Pompeo (n 2), accessed 15 April 2022. 41 ILC Report (n 29), Conclusion 15, p. 121. 42 Ibid .

43 VCLT (n 4), Art. 2(1)(a); ILC Report (n 22), p. 187; VCLT II (n 5), Art. 2(1)(a); ILC Report (n 27), p. 17. 44 KLABBERS, J. The Concept of Treaty in International Law (Kluwer Law International, The Hague 1996), p. 51. 45 Charter of the United Nations (adopted on 26 June 1945, entered into force on 24 October 19459) 1 UNTS XVI (UN Charter), Art. 102 (1).

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