This chapter is devoted to specific methods of interpreting international law and, in particular, to the reasons for their application. I maintain that, in order to fulfil their international obligations, States must apply the methods of interpretation of international law, namely textual, systematic, purposive and historical interpretation. Contrary to what is often assumed, methods of interpreting national and international law have the same characteristics. The differences between them are due to certain characteristics of national legislation compared to international law. To identify methods of interpretation of international law, I use domestic law and legal theory, the Vienna Convention on the Law of Treaties and the draft conclusions of the International Law Commission on the identification of customary international law. An important statement I make in this chapter – and one that challenges mainstream science – is that the above four methods govern the interpretation of treaties, but also the interpretation of customs and general principles. In national law1341, the historical approach1342 is generally on an equal footing with other canons, but its use is sometimes accompanied by reservations. In international law, the historical method can only be applied if certain conditions are met. With regard to the interpretation of the treaty, article 32 of the Vienna Convention on the Law of Treaties provides that travaux préparatoires are only “supplementary means of interpretation”. This complementarity had been emphasized by international tribunals prior to the adoption of the vclt,1343 but the point was controversial in the process of drafting the Convention.1344 The hierarchy between Article 31 and Article 31 of the Convention 32 VCLT clashes with the phenomenology of judicial decision-making,1345 and this hierarchy is often blurred in practice.
The ICJ and the PCIJ often carried out preparatory work, even if the conditions of Article 32 vclt were not met.1346 The European Court of Human Rights was also not entirely consistent in its practice.1347 Some States also have the complementary character of the historical interpretation in relation to cil.1348 49Ch. de Visscher, “Méthode et système en droit international”, RCADI, Vol. 138, 1973, pp. 75-79. Descriptive research questions are questions about the state of affairs as they are. Much of the traditional international jurisprudence is descriptive in that it attempts to describe “law” as it is, whether in an abstract way (e.g., “What is the content of the monetary gold principle in international jurisprudence?”) or in relation to a particular situation. For example, in their excellent articles on Yemen, Tom Ruys and Luca Ferro examine the Saudi-led intervention in the Yemeni civil war and question whether this intervention is legitimate. [3] From a theoretical point of view, this type of research can generally be described as positivist, in the sense that it considers only legally relevant sources (the lex lata) as autonomous bodies of knowledge.
We can call such questions descriptive teaching research questions because they attempt to analyze and describe teaching from an internal perspective. Of course, some doubt that it is even possible to describe authoritatively what the law is, beyond the very basic statements, without making a normative judgment about what the law should be. One could even say that the simple decision to discuss law as an autonomous sphere is a value-laden decision. For more than a century, these and related criticisms have been directed against teaching through realistic and critical legal approaches both at home and abroad. [4] This has led to a gradual marginalization of these research questions, at least in the United States. From a global perspective, however, doctrinal research on international law remains a central focus of research. Sources of international law include international practice (general State practice accepted as law), treaties and general principles of law recognized by most national legal systems. International law may also be reflected in the international comity, practices and customs adopted by States for the maintenance of good relations and mutual recognition, such as: the salutation of the flag of a foreign ship or the enforcement of a judgment of a foreign court. 15It should be noted, however, that in order to prove the existence of a specific rule of international law, the various elements which we must take into account in proving that evidence sometimes include the rational reasons for its existence or, in other words, the reasons which explain and justify its content.
Fourth, textual interpretation can (and often) be criticized if it ignores other methods of interpretation. However, the fact that unilateral and “textualist” approaches are erroneous does not lead to the conclusion that the textual interpretation is erroneous. For example, the use of textual interpretation does not require approval of originalism (loc. cit., chapter 2, 5.1). It is true that interpreters, because they are integrated into a communicative practice, cannot help but look at the ordinary meaning. However, text interpretation is a standalone method, although other methods may also require text interpretation and vice versa. The emphasis on ordinary meaning, however banal (and central) it may seem, is a distinct way of determining the law. Moreover, the interpretation in legal interpretation is not the text itself, but a social fact expressed (mostly, but not always)1210 in words.
These observations are contained in the ILC`s analytical guides on contract law (“Government Opinions”, , in particular ) and the identification of Cil (“Government Opinions”, ). See the examples given by Hersch Lauterpacht, “Les travaux préparatoires et l`interprétation des treaties” (1934) 48 Recueil des cours de l`Académie de droit international 799 ff. See also Ris (No. 1233) 112-113. Many treaties establish bodies to oversee their implementation or interpret their provisions (“treaty bodies”). These bodies, in turn, draft their own documents, decisions and comments. This is a particularly important feature of international human rights treaties. Fortunately, the United Nations maintains a searchable database of treaty bodies where you can search for virtually any type of treaty body document. For example, you can find various reports submitted to these bodies by States; You can also find decisions (“case law”) of treaty bodies, as some of them have the power to rule on individual and inter-State claims.
For more information on human rights law research, Georgetown Law has created this excellent guide (on secondary and primary sources). While these perspectives must undoubtedly be taken into account in understanding and evaluating national legal practice of international law, such a comprehensive study would be beyond the scope of this book. While it is clear that States (and thus their courts) must respect the idiosyncratic interpretative practice of States that has developed at the international level with respect to specific substantive regimes of international law, a thorough analysis of these interpretative particularities would require a significant broadening of the scope of my study. My aim is not to give a classic overview of Swiss judicial practice, nor to provide a complete account of this practice on the basis of the different laws that the courts regularly interpret and the regimes to which these acts belong. Rather, I assess the legality and quality of Swiss judicial practice as a whole. In this chapter, I argue that, in order to comply with their international obligations, States must apply the methods of interpretation of international law, namely textual, systematic, purposive and historical interpretation. As trivial and uncontroversial as this point may seem, it is too often dismissed or overlooked by scientists and courts. This neglect of interpretive methods compromises the legality and predictability, clarity and consistency of legal reasoning.