CYIL vol. 8 (2017)

CYIL 8 ȍ2017Ȏ THE IMPORTANCE OF CUSTOMARY LAW FOR THE CODIFICATION OF THE LAW … Research conducted at Harvard University at the beginning of the 1930s showed that then there already existed a rich collection of scientific work covering treaty interpretation, just as the PCIJ, arbitral tribunals and also domestic courts case-law are relevant. 14 The outcome of this Harvard research was a draft convention with detailed commentary. 15 It contained in essence the same rules of interpretation that we know nowadays from the VCLT. The main emphasis was put on “ the general purpose, which it (=the treaty) is intended to serve ”. This corresponds with the traditional American inclination to the pragmatic and teleological interpretation of law. This entails the preference of the subjective interest of the parties for objective evaluation of treaty text in its overall context, including “ the subsequent conduct of the parties ”. In the 1950s, the interpretation of treaties was examined by the Institute of International Law ( L’Institut de Droit international – IDI), a leading forum of unofficial codification. In 1956, the IDI adopted a resolution on treaty interpretation. 16 This topic in the IDI was elaborated by Hersch Lauterpacht, who later became Special Rapporteur at the UN International Law Commission and worked on the official codification of treaty law. The IDI resolution includes the natural and common meaning of terms as a basis for interpretation and further mentions general context, good faith, fundamental principles of international law and the object and purpose of the treaty, as well as subsequent practice in the effective application of the treaty and preparatory materials. The agreement on any special meaning different from the natural and common one is allowed to the treaty parties. The fact that as early as in the first half of the 20th century the unofficial codification grasped basically the same methods and principles as the VCLT later can be understood as an important piece of proof of the customary nature of its provisions concerning interpretative rules. The codified general rule of interpretation is intended to serve all the interpreting subjects, not only for treaty parties or international courts of justice. The methods of interpretation codified in the VCLT are according to the prevailing doctrinal statement an expression of earlier custom 17 and “ are not open to challenge ”. 18 This statement was presented at the end of the 1950s by the UN ILC Special Rapporteur Gerald Fitzmaurice. 19 The same conclusion is reached by a majority of contemporary renowned commentaries to the VCLT. 20 There are 14 GARDNIER, Richard, Treaty Interpretation. Oxford University Press, Oxford, 2008, p. 57. 15 Harvard Draft Convention on the Law of Treaties , annex to the American Journal of International Law , vol. 29, 1935; DÖRR, Oliver, SCHMALENBACH, Kirsten (eds.), Vienna Convention on the Law of Treaties - A Commentary , Berlín, Springer, 2012, p. 21. 16 INSTITUT DE DROIT INTERNATIONAL, Session de Grenade – 1956 . Résolution : Interprétation des traités (Rapporteur: M. Hersch Lauterpacht). [on-line] [accessed 12 December 2016] < http://www.justitiaetpace.org/ idiF/resolutionsF/1956_grena_02_fr.pdf >. 17 MONACO, Riccardo, CURTI GIALDINO, Carlo, Manuale di diritto internazionale pubblico , 3rd edition, UTET Giuridica, Rome, 2009, p. 212. Judgment of ICJ in the territorial dispute between Libya and Chad, ICJ Reports , 1994, p. 21. 18 HOLLIS, Duncan (ed.), The Oxford Guide to Treaties , Oxford University Press, Oxford, 2012, p. 476. 19 ŠTURMA, Pavel, ČEPELKA, Čestmír, BALAŠ, Vladimír, Právo mezinárodních smluv (The Law of Treaties) , Aleš Čeněk, Pilsen, 2011, p. 10. 20 See PETERS, Christopher, Subsequent Practice and Established Practice of International Organizations: Two Sides of the Same Coin? Goettingen Journal of International Law , Vol. 3, 2011, p. 619, DÖRR, Oliver, SCHMALENBACH, Kirsten, Vienna Convention on the Law of Treaties – A Commentary , Berlín, Springer, 2012, p. 523; CORTEN, Olivier, KLEIN, Pierre , The Vienna Conventions on the Law of Treaties – A Commentary . Volume I. Oxford University Press, 2011, pp. 807, 812.

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