¹ “New Approaches to the Study of International Law,” 61 Am. J. Int’l L. 477, 486 (1967).

² “Towards a Theory of International Obligation,” 8 Va. J. Int’l L. 300 (1968). The article appears in substantially the same form in Schwebel (ed.), The Effectiveness of International Decisions 9 ( 1971 ), to which references will be made.

³ Ibid., 11.

⁴ Classic studies are Lauterpacht, The Function of Law in the International Community, Ch. XX (1933); Brierly, The Basis of Obligation in International Law (1958). See also Korowicz, , Introduction to International Law 1–156 (1959)Google Scholar; Kelsen, , The Principles of International Law 1–173 (2nd ed. Tucker, 1966)Google Scholar; Jenks, , “The Will of the World Community as the Basis of Obligation in International Law,” in Law, Freedom and Welfare 83–100 (1963).Google Scholar

⁵ Schachter, op.cit. supra note 2, at 9. Schachter himself proposes some considerations relevant to a theory of the basis of obligation.

⁶ For a discussion of the legal philosophy of St. Thomas Aquinas, see Friedmann, Legal Theory 108–12 (5th ed., 1967).

⁷ The view was advanced by the German professor Jellinek, and later elaborated upon by Triepel: see Korowicz, op. cit. supra note 4, at 44–55.

⁸ Lauterpacht, op. cit. supra note 4; Jenks, op. cit. supra note 4.

⁹ Hart, The Concept of Law 79–88 (1963).

¹⁰ This has been done through the institution of courts, the creation of bodies like the International Law Commission and the convening of multilateral conferences with a law-making purpose.

¹¹ See e.g., Higgins, , The Development of International Law through the Political Organs of the United Nations (1963).Google Scholar

¹² The first five reports of the Special Rapporteur on this topic are found in the following Yearbooks of the International Law Commission: 1963 Vol. Π, 159; 1967 Vol. II, 133; 1968 Vol. II, 119; 1969 Vol. II, 1; 1970 Vol. II, 1. The sixth report is found in A/CN.4/241 and Adds 1–6.

¹³ In 1971, after reviewing a report of a Sub-Committee (A/CN.4/250), the International Law Commission appointed M. Reuter as Special Rapporteur for the topic of treaties concluded between states and international organizations or between two or more international organizations; for the first report of the Special Rapporteur, see A/CN.4/SR. 1153.

¹⁴ In other cases, however, particularly with respect to the activities of international organizations, it will not be clear whether a suggested rule is in fact authoritative. The lack of acceptance of clear rules for identifying rules or norms is one of the principal problems of international law.

¹⁵ Hart, op. cit. supra note 9.

¹⁶ I am grateful to my colleague, Professor J. C. Smith, for allowing me to read chapters of his forthcoming book, Legal Obligation, which has helped to clarify some of my thinking on this topic. For an earlier discussion of aspects of obligation under international law, see McRae, , “Sovereignty and the In-ternational Legal Order,” 10 U.West.Ont.L.Rev. 56 ( 1971 ).Google Scholar

¹⁷ Hart, op. cit. supra note 9, at 91–96.

¹⁸ “The conjunction of common expectations concerning authority with a high degree of corroboration in actual operation is what we understand by law,” McDougal, and Lasswell, , “The Identification and Appraisal of Diverse Systems of Public Order,” in McDougal and Associates, Studies in World Public Order 14 (1960).Google Scholar

²⁰ Ibid., 16.

¹⁹ Supra, note 18.

²¹ Austin, The Province of Jurisprudence Determined (Library of Ideas ed., 1954).

²² Hart, op. cit. supra note 9.

²³ Ibid., 95. One criticism of Hart’s analysis is that, by relegating the idea of a sanction to a place amongst the various secondary rules of adjudication, he had oversimplified the factual importance of the sanctioning process to any legal system; see the point made by McDougal and Lasswell, op. cit. supra note 18, at 16.

²⁴ Hart, op. cit. supra note 9, at 113: “There are therefore two minimum conditions necessary and sufficient for the existence of a legal system. On the one hand those rules of behaviour which are valid according to the system’s ultimate criteria of validity must be generally obeyed, and, on the other hand, its rules of recognition specifying the criteria of legal validity and its rules of change and adjudication must be effectively accepted as common public standards of official behaviour by its officials.”

²⁵ McDougal, , Lasswell, , and Reisman, , “Theories About International Law: Prologue to a Configurative Jurisprudence,” 8 Va. J. Int’l L. 188, 251 (1968).Google Scholar

²⁶ Ibid., 257.

²⁷ Hart, it is to be noted, concluded as a result of his own analysis that international law resembled a “regime of primary rules”: op. cit. supra note 9,at 222. This evoked the comment from Friedmann, op. cit. supra note 6, at 288, that Hart had failed to apply his own approach correctly to international law.

²⁸ The point is reiterated by Schachter, op. cit. supra note 2, at 16.

²⁹ See supra 88.

³⁰ Schachter in his study cited (supra note 2) indicated some of the directions such an enquiry should take.

³¹ Brierly, op. cit. supra note 4, at 66.

³² One of the more perceptive analyses of state behaviour in this regard is found in Kaplan and Katzenbach, The Political Foundations of International Law (1961), where it is stated (at 10): “…states ’consent’ to international prescriptions in the same sense as individuals ‘consent’ to existing laws. They recognise the general need for a system of order, they regard the bulk of existing regulations as either desirable or at least tolerable, and they accept what remains because they have to — because they lack the ability to change it.”

³³ The relationship of an employee to an international organization is, however, not wholly contractual; there are elements of both contract and statute: see Kaplan v. Secretary-General, Judgments of the U.N. Administrative Tribunal, Judgment No. 19, (1950–57), at 71. For the most comprehensive treatment of the position of employees of international organizations, see Akehurst, , The Law Governing Employment in International Organizations (1967).Google Scholar

³⁴ These agreements are discussed in Mann, “The Proper Law of Contracts Concluded by International Persons,” 35 Brit. Yb. Int’l L. 34 (1959).

³⁵ Kelsen, The Law of the United Nations 313 (1950).

³⁶ “…any contract which is not a contract between states in their capacity as subjects of international law is based on the municipal law of some country,” Serbian Loans Case, P.C.I.J., Ser. Α., Nos. 20/21, at 41 (1929).

³⁷ This is the approach of Mann, op. cit. supra note 36. The classic statement of the common law rule to this effect is found in the advice of the Privy Council in Vita Food Products Inc. v. Unus Shipping Co., Ltd. (In Liquidation), [1939] 1 All E.R. 513, 521 (Lord Wright): “It is now well settled that, by English law … the proper law of the contract ‘is the law which the parties intended to apply.’ ”

³⁸ Generally this is now taken to be the law with the “closest and most real connection”: see e.g., Etler v. Kestesz (i960), 26 D.L.R. (2d) 209, 2t8 (Ont. CA.).

³⁹ Verdross, , “Quasi-International Agreements and International Economic Transactions,” 18 Yearbook of World Affairs 230 (1964).Google Scholar The article repeats a view earlier expressed by the learned author in 18 Zeitschrift für auslandisches öffentliches Recht und Volkerrecht 635 (1958).

⁴⁰ McNair, , “The General Principles of Law Recognised by Civilized Nations,” 33 Brit. Yb. Int’l L. 1, 18 (1957).Google Scholar

⁴¹ The term is derived from Jessup, Transnational Law (1956), and is treated by Verdross as equivalent to “quasi-international law” Verdross, “Quasi-International Agreements and International Economic Transactions,” op. cit. supra note 39, at 232.

⁴² Akehurst, op. cit. supra note 33; “Settlement of Claims by Individuals and Companies against International Organizations,” 37/38 Yb. of A.A.A. 69 (1967–68).

⁴³ Jenks, , The Proper Law of International Organizations 25 (1962).Google Scholar

⁴⁴ Akehurst, op. cit. supra note 33, at 261, considered that the criterion of what constitutes a separate legal system is uncertain and (at 263) in any event the question whether the internal law of international organizations is part of international law is of little practical import.

⁴⁵ As D. P. O’Connell has pointed out, both monist and dualist approaches to the relationship between international and municipal law are deficient in failing to recognize that “international law and municipal law are concordant bodies of doctrine,” each subject to its own jurisdictional rules; International Law, Vol I, at 426 (1965).

⁴⁶ Cited supra note 36.

⁴⁷ The view is suggested by Kelsen, op. cit. supra note 35, at 314. After a review of practice, Seyersted, , “Jurisdiction over Organs and Officials of States, the Holy See and Intergovernmental Organizations,” 14 Int’l & Comp. L.Q. 31 and 493 at 505 (1965),CrossRefGoogle Scholar concluded that the view is untenable.

⁴⁸ The English conflict of laws rule that refers the question of capacity to contract to the proper law of the contract has not been reached without dispute. The alternative approach has been to treat capacity generally as an incident of status and hence governed by the law of the domicile; see discussion following Rule 130, Dicey, and Morris, , The Conflict of Laws 744–48 (8th ed., 1967).Google Scholar

⁴⁹ Akehurst, op. cit. supra note 33, at 254.

⁵⁰ Ibid., 252. Dr. Akehurst noted the possibility of an objection based on the personality of the individual but he commented that this seems “an extremely doctrinaire and outdated view to take in the second half of the twentieth century.”

⁵¹ This assumes that the question is raised before an international tribunal; if it were raised before a municipal tribunal, it is not wholly clear that it would be accepted as a valid choice of law, although some writers assume that it would; Mann, op. cit. supra note 34, at 46. However, municipal courts generally view international law differently from foreign law; for example they do not require its proof by experts. Whether, too, the tribunal has been constituted under municipal or international law may be in question. For a discussion of this problem, see Seyersted, , “Settlement of International Disputes of Intergovernmental Organizations by Internal and External Courts,” 24 Zeitschrift für auslandisches öffentliches Recht und Volkerrecht I, 61–71 (1963).Google Scholar

⁵² In view of the limited bargaining power of an individual seeking employment with an international organization, his contribution to the development of new kinds of substantive rules is admittedly limited.

⁵³ Supra 97–98.

⁵⁴ Presumably, although adherents of this approach do not make the point clear, this is a choice of law rule of international law, unless it is argued that the parties’ existence and activities occur solely within this separate system of law. If, however, the choice of law rule is a rule of international law, then the approach presupposes much of the earlier discussion concerning the view that international law governs the contract. Thus it assumes that individuals or corporations have a status under international law in so far as that law includes a choice of law rule applicable to their behaviour.

⁵⁵ Verdross, op. cit. supra note 39, at 233, defined international law as “the law governing the relations between states and other international persons,” which he described as the definition accepted by “the best modern writers as well as by the International Court of Justice.”

⁵⁶ Article 38(1) (c) of the Statute of the International Court of Justice.

⁵⁷ This “internal law” or “international administrative law” can apply only to activities that are related ultimately to the constitution of an organization; this will include relations between member states, the functions and powers of the organs of the organization and contracts of employment. Other kinds of contracts, such as contracts for goods and services or contracts of loan, must be governed by the “external” law affecting the organization, for the contracting party, not being constituted under or deriving authority from the organization’s constitution, can in no way be subject to it.

⁵⁸ “International administrative law is not, however, a part of public international law because it does not apply to the relations of states …”: Carls-ton “International Administrative Law: A Venture in Legal Theory,” 8 Journal of Public Law 329, 340 (1959). Carlston stated also that “the binding quality of international administrative law, insofar as states and the organization itself are concerned, rests on the principle of pacta sunt servanda,” idem.

⁵⁹ The argument is developed in Akehurst, op. cit. supra note 33, at 258–61.

⁶⁰ See Report of the International Law Commission to the General Assembly covering the work of its 14th Session, II Yb. I.L.C. 160–61 (1962). The decision had been made originally in 1951 but subsequent rapporteurs had succeeded in broadening the scope of the draft articles.

⁶¹ Kearney, and Dalton, , “The Treaty on Treaties,” 64 Am. J. Int’l L. 502–03 (1970).CrossRefGoogle Scholar

⁶² Res. 2501 (XXIV) adopted November 12, 1969. Since then discussions of the law governing the agreements of international organizations have appeared: see Zemanek, (ed.), Agreements of International Organizations and the Vienna Convention on the Law of Treaties (1971)Google Scholar; Zemanek, , “Agreements Concluded by International Organizations and the Vienna Convention on the Law of Treaties,” 1971, U. of Tol. L.R. 145.Google Scholar

⁶³ Artide 3 of the Vienna Convention on the Law of Treaties allows the application of the rules of the Convention to agreements of international organizations where those agreements would be so subject under international law independently of the Convention. Though no specific provision is made, there seems no reason why international organizations could not provide in their agreements that the Vienna Convention was to govern.

⁶⁴ This is particularly so in the area of resolutions of the organs of international organizations: see, for example, Higgins, op. cit. supra note u: Falk, , “On the Quasi-Legislative Competence of the General Assembly,” 60 Am J. Int’l L. 782 (1966).CrossRefGoogle Scholar

⁶⁵ McRae, , “Co-operation Agreements and the Law Relating to Agreements Concluded by International Organizations,” in Zemanek, (ed.), Agreements of International Organizations and the Vienna Convention on the Law of Treaties 5–18 (1971).Google Scholar