Sources of International Law

Martti Koskenniemi

• Publisher: Routledge
• Year: 2017
• eBook ISBN: 9781351548168
• Topic: History
• Subtopic: International Law
• Index: History

A collection of essays on the various aspects of the legal sources of international law, including theories of the origin of international law, explanation of its binding force, normative hierarchies and the relation of international law and politics.

Part I
Sources Theory

[1]
Towards a Theory of International Obligation

by Oscar Schachter *
United Nations Institute for Training and Research

I. The Practical Import of Theory

It seems especially fitting to devote this essay to some reflections on a basic—some would say meta-juridical—question that appears to be at the heart of some of our present intellectual perplexities in international law. As a subject, the "foundation of obligation" is as old as international law itself; it had a prominent place in the seminal treaties of the founding fathers—Suarez, Vittoria, Grotius, Pufendorf et al—and it remained a central issue in the great controversies of the nineteenth century.¹ In our century it has had a lesser place; it was largely overtaken by the discussion of "sources" and evidence, centered around Article 38 of the Statute of the International Court.² Although subordinated, it was not neglected and each of the leading scholars of the twentieth century found himself impelled to advance a fresh analysis. No single theory has received general agreement and sometimes it seems as though there are as many theories or at least formulations as there are scholars. We can list at least a baker's dozen of "candidates" which have been put forward as the basis or as one of the bases) of obligation in international law:

• (i) Consent of states³
• (ii) Customary practice⁴
• (iii) A sense of "rightness"—the juridical conscience⁵
• (iv) Natural law or natural reason⁶
• (v) Social necessity⁷
• (vi) The will of the international community (the "consensus" of the international community)⁸
• (vii) Direct (or "stigmatic") intuition⁹
• (viii) Common purposes of the participants¹⁰
• (ix) Effectiveness¹¹
• (x) Sanctions¹²
• (xi) "Systemic" goals¹³
• (xii) Shared expectations as to authority ¹⁴
• (xiii) Rules of recognition ¹⁵

On looking at this wide array of ideas concerning the "true" or "correct" basis of obligation in international law it may be wondered, on the one hand, whether the choice of a "basis" has any great practical significance and, on the other, whether the diversity of opinion does not reveal a radical weakness in the conceptual structure of international law.

For some pragmatically-inclined international lawyers, the issue is not likely to be regarded as important. As long as the obligation itself—the legal norm or prescription—can be identified in one of the so-called formal sources—treaty or custom or in general principles of law—it seems to matter little what the underlying basis of the obligation may be. It is, therefore, understandable that most contemporary treatises and textbooks on international law pass quickly and lightly over the problem of the "foundation." Like the chaplain's opening prayer at public meetings, it has little effect on what is said afterwards. The practical international lawyer is supposed to be concerned not with the foundation of obligation but with the so-called "sources," formal and material.¹⁶

But this is more easily said than done. Somehow conceptions as to the basis of obligation arise time and again, and not only in theoretical discussion about the binding force of international law. They come up in concrete controversies as to whether a rule of law has emerged or has been terminated; whether an event is a violation or a precedent; and whether practice under a treaty is accepted as law. They are involved in dealing with situations in which solemn declarations, couched in legal terminology, are adopted by official bodies which have no formal authority to lay down prescriptive rules. They come up when there is substantial variance between what is preached and what is practiced; or when consensus (or expectations) are limited in geographical terms or in duration. These are not, of course, new problems and over the years they have been the subject of much jurisprudential writing. But in the last few years the general problem has assumed a new dimension. The peculiar features of contemporary international society have generated considerable normative activity without at the same time involving commensurate use of the formal procedures for international "legislation" and adjudication.

It may be useful to recall the main factors which have emerged in international life in the last few years to give enhanced importance to problems of indeterminancy of obligation.

First, there has been the much-discussed "quasi-legislative" activity by the General Assembly and other United Nations bodies purporting to lay down, expressly or by implication, requirements of State conduct or to terminate or modify existing requirements.¹⁷

Second, there has been a recognition of so-called "rules of the game," based on implicit understandings or unilateral actions and acquiescence. This has been a notable feature of Great Power behavior in regard to their use of armed force.¹⁸

Third, there have been the social revolutions which have overturned traditional orders and have challenged the assumptions on which prior conceptions of authority were based.¹⁹

Fourth, the growing interdependence of States—especially in economic and technological activities—has vastly increased patterns of cooperation and reciprocal behavior which have not been institutionalized in the traditional modes of lawmaking.²⁰

Fifth, the increased "permeability" of national States has resulted in a diminishing barrier between matters of international concern and those of domestic jurisdiction.²¹ Related to this is the fact that the United Nations Charter—particularly its articles relating to respect for human rights and self-determination of peoples—has brought domestic activities before collective organs for appraisal on the basis of international criteria.

Sixth, the expansion of science and technology with international impact both beneficial and harmful has given rise to informal means of setting standards and exercising supervision without entering into tight and tidy legal instruments.²²

The mere statement of these trends indicates how extensive and far-reaching are normative processes which cannot easily be placed into the categories of treaty and customary law, at least as these terms have been applied traditionally. Lawyers are made uncomfortable by this and they ceaselessly endeavor to pour the new wine into the old bottles and to market it under the time-honored labels. They will treat many of the cases as problems of treaty interpretation; others will be dealt with on the assumptions applicable to traditional customary law. But when we examine the arguments and the grounds for decision, we find more frequently than not that the test of whether a "binding" rule exists or should be applied will involve basic jurisprudential assumptions. Even the International Court of Justice, which is governed expressly by Article 38 of its Statute as to the sources of law, has demonstrated time and again that in their deliberative process the judges have had to look to theory to evaluate practice.

We can readily illustrate this by brief references to judicial opinions which have employed criteria such as the will of the community, customary behavior, the sense of "rightness," reason, necessity, natural law, major purposes and so on. In the 1966 South West Africa Cases, the opinions of Judges Jessup and Tanaka provide good examples.²³ Judge Jessup found that the accumulation of expressions of condemnation of apartheid especially as recorded in the resolutions of the General Assembly was "of decisive practical and juridical value" in determining the "international community" standard to be used in the interpretation of the requirement in Article 2 that South Africa promote the well-being of the inhabitants.²⁴ In effect, this meant that the Assembly resolutions established a conclusive, not merely a rebuttable, presumption as to the meaning of well-being. Judge Tanaka took a different ground. He concluded that, while a single resolution is only recommendatory, the repetition by overwhelming majorities of condemnation of apartheid has established a customary rule of law.²⁵ He also found the rule against apartheid to constitute a "general principle of law"—not because it is a principle common to diverse legal systems, but as a rule jus naturale, "valid through all kinds of human societies" and derived from the concept of "man as a person." Its validity therefore rests on a basis that has a "supra-national and supra-positive character."²⁶

In other I.C.J, cases we can find reliance on major purposes,"²⁷ on the necessity of a sense of Tightness,²⁸ and on humanitarian values.²⁹ In the Anglo-Norwegian Fisheries Case,³⁰ the factor of strong economic interest of one State directly affected supported a judgment that practice of that State should be accepted as law; and in the Corfu Channel judgment,³¹ the majority rejected the British claim to "self-preservation" on the ground that it was a manifestation of a policy of force such as "has in the past given rise to serious abuses." These are all criteria not easily discoverable in the text of Article 38.

When we look beyond the judicial arena to the political bodies and to the diplomatic arena, we find, not surprisingly, an even greater number of situations in which the distinction between "binding" and "non-binding" is not easily determinable. Perhaps the most important group of such situations falls into the second category of developments mentioned above, namely, the "rules of the game" or tacit understandings. In this category one might include what is often described as the modus vivendi between the two major powers not to use or introduce armed force in the sphere of influence of the other or to upset the existing balance between them in any significant way. Some observers have referred to the "line" accepted by the major powers, running through the divided countries and between other critical areas as if it had been laid down in treaties.³² The Cuban quarantine and missile crisis is said to exemplify the operation of that general rule.³³ Other such rules of the game have been posited in more limited situations. For example, some would say there has been a tacit rule on the part of the two major powers not to give nuclear weapons to third parties, including their respective allies. These rules or tacit agreements are generally not characterized by lawyers as legal obligations; their violation would not be thought of as ground for legal liability and they are presumed to be terminable at will. On the other hand, their termination may well give rise to sanctions in the form of public condemnation (as in the violation of the Nuclear Test Moratorium) or, more important, to counter-action by the other party. In some cases, these "rules of the game" constitute the most crucial international obligations of our time.

As we go down the list of the six categories mentioned above, other situations come to mind. Consider, for example, the effect of anticolonialism (expressed in declarations of the General Assembly and in other supposedly "non-binding" assertions) on the meaning of domestic jurisdiction and self-determination.³⁴ Or consider the changing conceptions regarding the taking of private property and their effect on the existing "rule" concerning compensation for expropriation.³⁵ In the field of economics and technology, there is uncertainty as to the legal authority of emerging principles of international trade and economic assistance for the benefit of the developing countries which have not yet assumed conventional legal form; yet they exhibit some measure of practical efficacy and give rise to widespread expectations as to their future application.³⁶

In all of these cases the traditional sign-posts of legal obligation have limited utility, at the very least they call for further analysis and possibly, as Richard Falk has suggested, for a more adequate theory of the basis of legal obligation in international society.³⁷ The observations that follow will attempt to suggest some of the considerations relevant to a more adequate theory.

II. An Approach to a Theory of International Obligation

Hardy Dillard, in a recent, typically felicitous essay, expressed concern over the emphasis on certain modes of inquiry to the exclusion of others. To know the "why" of things, we need, he suggested, a "perspective that looks both forwards and backwards. It may well elude a mind bent exclusively on fact-finding or one geared to solving specific problems."³⁸ It will also elude—and I know Dean Dillard will agree—a mind exclusively geared to the a priori and intuitive approach. If we are to snare so elusive a quarry as international obligation, we may need several nets and to spread them all wide.

The trouble with nets—or "conceptual frameworks" as they are now called—is that we can easily get tangled in the net and lose sight of the quarry. The wider the net, the greater the risk. We have seen the entanglements in the grand "top down" systems that work their way from all-embracing concepts on high through intermediate hypotheses to more specific assertions which sometimes are verifiable and sometimes are not. Hegel and Marx provide classic examples; Talcott Parsons is a good contemporary example.³⁹ Still, a system or framework seems to be essential if we are to organize a vast amount of material and relate it to our purposes....

Table of contents

• Cover
• Half Title
• Title
• Copyright
• Contents
• Acknowledgements
• Series Preface
• Introduction
• PART I SOURCES THEORY
• PART II RELATIVE NORMATIVITY
• PART III CUSTOMARY LAW
• PART IV GENERAL PRINCIPLES AND EQUITY
• PART V THE COMPLETENESS OF THE LAW
• Name Index