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Human Rights in Customary Law: An Attempt to Define Some of the Issues

Published online by Cambridge University Press:  30 July 2015

HUGH THIRLWAY
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Abstract

Prepared as a working paper for the International Law Commission, this article discusses whether there can be said to be a general customary law of human rights, or whether any such customary law might be of a special nature.

Keywords

customary lawhuman rightshuman rights treatiesInternational Law Commissionstate practice

Information

Type
INTERNATIONAL LAW AND PRACTICE
Information
Leiden Journal of International Law , Volume 28 , Issue 3 , September 2015 , pp. 495 - 506
Copyright
Copyright © Foundation of the Leiden Journal of International Law 2015 

1. Introduction

In 2014 the writer was asked to prepare a working paper in the context of the current work of the International Law Commission (ILC) on the question of the identification of international custom, as a source of law. That paper took as points of reference the two reports prepared by the Special Rapporteur, Sir Michael Wood,Footnote 1 and the Statement of the Chairman of the ILC Drafting Committee dated 7 August 2014. The paper was discussed at a workshop organized by the UK Foreign Office and the University of Oxford on 15 October 2104. It has subsequently been suggested that it might be made more widely available; for that purpose, it is presented here, with some small revisions, mostly of form, but no attempt has been made to update or expand it, in the light of the discussion or otherwise. It is offered to the reader, as it was to the participants in the workshop, not as a perfected thesis but merely a statement of a number of ideas for reflection.

The project of the ILC, at its present stage, is designed to be general, applicable to custom-formation as a process regardless of the field of law in which the rules developed are to operate. Bearing in mind the special nature of human rights law,Footnote 2 in particular such part of it as may be considered to be customary in nature, might the ILC texts provisionally adopted or contemplated need to be added to, reconsidered, adjusted, or qualified to take account of that special nature?Footnote 3 It was suggested that in this context this paper should consider the following questions, in relation to the formation of human rights norms:

  1. 1. The role of treaties in the formation of custom;

  2. 2. statements versus acts as state practice; and

  3. 3. the relationship between opinio juris and state practice.

In accordance with the general view in the Commission,Footnote 4 the Special Rapporteur has adopted the traditional two-element conception of international custom-formation, which is also consistent with the accepted interpretation of Article 38 of the ICJ Statute. The elements are general practice (see the Draft Conclusions provisionally adopted) and opinio juris. Taking that article to be an exhaustive statement of the sources of international law, a norm protecting human rights could thus be customary law, or contained in a treaty, or result from general principles of law. Strictly, only the first concerns us here, although the impact of treaties on custom needs to be considered. It has been suggestedFootnote 5 that human rights, while not based on customary law, fall into a category of ‘non-conventional law’, not created by treaty, but not subject to the strict requirements of custom-formation; this approach, which is difficult to square with Article 38,will be considered below. There have been efforts to derive human rights from the ‘general principles of law’,Footnote 6 and there are ICJ dicta which lend support to this approach, at least in respect of certain rights,Footnote 7 but this is again a question outside the scope of the ILC's current study.

The Special Rapporteur has, in his First Report, himself raised the question of possible variation of custom-formation requirements in the case of special regimes: ‘One issue that the Commission will need to address is whether there are different approaches to the formation and evidence of customary international law in different fields of international law, such as international human rights law . . .’.Footnote 8 In his Second Report, he referred again to ‘the question whether there might be different approaches to the identification of rules of customary international law in different fields’, and gave as example ‘suggestions in the literature, occasionally echoed in practice, that in such fields as international human rights law, international humanitarian law, and international criminal law, among others’, the presence of both state practice and opinio juris is not required, but ‘one element may suffice in constituting customary international law, namely opinio juris’. He concluded however that ‘the better view is that this is not the case’.Footnote 9 This of course does not preclude further discussion in the present context, but for the present the ‘one-element’ theory will therefore not be further examined here.

2. Is there an international customary law of human rights?

It appears to be still a perfectly tenable view that there is in fact no general international customary law of human rights,Footnote 10 all the existing rights and obligations of states in this domain (with some exceptions) being based, mediately or immediately, on treaty commitments, or on general international declarations that have in some manner (but what manner?) a similar degree of binding force.Footnote 11 This is not however the universal view; for a number of scholars, there are norms of human rights law that are custom-based, although generally these are seen as somehow deriving from an adaptation of international instruments, rather than as having emerged from the interchange of state relations that normally constitutes the material element of custom. Thus for Buergenthal, some of the provisions of the Universal Declaration of Human Rights are ‘deemed to have become customary international law’Footnote 12 (but what is the force and nature of that ‘deeming’ process?).Footnote 13

The view that there is as yet no customary law in this field is supported by (or perhaps derives from) the virtual absence of state practice in the traditional sense. One reason for this is the domination of the field by treaty instruments (see next section), and by tribunals established to oversee their workings, so that there exists a large measure of protection of human rights without any need for custom to play a role. At the risk of stating the obvious, however, one may note that there would seem to be a basic theoretical difficulty with the operation of traditional custom-formation in the field of human rights. International custom has traditionally derived from practice in the form of the effective interrelation of equal sovereign states: what the Rapporteur's provisional conclusions refer to as the conduct of states ‘on the ground’.Footnote 14 In principle, it results from acts (or omissions) with an inter-state aspect.Footnote 15 Historically, states have recognized the legality of another state's action, or the validity of a claim made, if the state concerned considers that, in the reverse case, it would expect or desire that its act would be accepted, or its claim be regarded as valid. The basis of such relations may be crudely expressed as ‘do as you would be done by’. The rights that emerge in this way, and the obligations that are the counterpart of those rights, are the rights and obligations of states toward one another. Seen in this light, the basis of customary law, it may be suggested, is less consentFootnote 16 than potential reciprocity. On that basis, states that have not reacted need not be taken to have consented, but merely to have tacitly recognized the merits of the solution arrived at;Footnote 17 and similarly the recognition of individual human rights does not need to be seen as something actively consented to.

A right recognized as (or claimed to be) a ‘human right’ is however, as its name implies, initially a right belonging to an individual human being, or a group of individuals. The corresponding obligation will (for our present purposes) generally rest on a state, but a state as seen from within and below, as it were, rather than a state seen laterally as an equal. A state may be obliged to respect the human rights of its citizens and the persons or groups within its territory; and an obligation to respect human rights may of course also rest on other individuals or groups, normally also within that territory. In either case, however, this obligation will exist because such is the domestic law of the state whose legislation is applicable, not (or not directly) as a matter of international law.Footnote 18 Another way of looking at the matter is to invoke the concept of domestic jurisdiction, and the recognized principle of sovereignty, that (in principle) what states do or do not do on their own territories is their concern alone; and it is a challenge to this principle (the ‘sovereignty paradigm’) that underlies one modern theory of customary human rights rule-formation.Footnote 19 There is no doubt that this principle or paradigm is no longer valid as regards the protection of treaty-based human rights in the domestic arena; but the influence there of customary law is less clearly established. States do react on an inter-state level to what they see as ‘grave and widespread’ breaches of the most essential human rights, but generally do not seek to interfere with each other's day-to-day respect, or lack of respect, for human rights.Footnote 20

If norms of human rights law rank as rules of customary law, it is generally held that the obligations that they enshrine must be obligations erga omnes, as ‘obligations . . . towards the international community as a whole’, according to the (obiter, and perhaps somewhat premature) pronouncement of the ICJ in the Barcelona Traction decision.Footnote 21 It is widely assumed that if an obligation is owed erga omnes, then the corresponding right must be owed erga omnes; but is this necessarily so?Footnote 22 If an alleged rule of customary law is of such a nature that it confers rights erga omnes, then the practice out of which it grew must show, not merely the development of an opinio that there is here a legal right, but of an opinio that that right is one exercisable erga omnes. Is subscribing to, for example, the Universal Declaration necessarily to be interpreted in that sense? Furthermore, that opinio should also be discernible in the form of interventions by states in each other's affairs for the protection of human rights, basing their claims on customary law, not merely on conventions, and even in the absence of a link of nationality; does modern practice show this unambiguously?Footnote 23

Taking these difficulties into account, it may be that little has changed since Oscar Schachter noted, as long ago as 1991, that ‘Whether human rights obligations have become customary law cannot readily be answered on the basis of the usual process of customary law formation’, and that none of the items of ‘evidence’ of custom advanced in support of a finding that human rights are part of customary law ‘conform to the traditional criteria’.Footnote 24 A tentative conclusion may be that, if there is a customary law of human rights, its processes of formation, while involving both a factual and a conceptual element, are not necessarily identical with those of general international law, and might therefore have to be given special examination by the ILC in the present context.

3. The impact of human rights treaties

The position in general as to treaty provisions becoming transformed into, or generating, customary law has been well expressed (or restated) as follows:

it is necessary that the provision concerned should, at all events potentially, be of a fundamentally norm-creating character such as could be regarded as forming the basis of a general rule of law; that there be corresponding settled State practice; and that there be evidence of a belief that this practice is rendered obligatory by the existence of a rule of law requiring it (opinio iuris sive necessitatis).Footnote 25

This was a finding by the European Court of Human Rights, and the rule of law contested was one of humanitarian law; the Court gave no indication that these aspects affected the application of the general two-element approach to the development of customary law.

Human rights law is dominated by international multilateral conventions, seconded by multilaterally-adopted non-conventional instruments setting out rights to be protected. The direct impact on states of such conventions is not within the domain of customary international law, and therefore not here to the purpose. The same is true of the non-conventional instruments to the extent that their provisionsFootnote 26 are regarded as having a quasi-treaty impact; whatever the merits of this approach, it too does not impinge on the ILC's current study of customary law. In general, the provisions of both are ‘potentially of a fundamental norm-creating character’. One view is that conclusion of, and participation in, human rights treaties may constitute ‘state practice’ (as in the US Restatement Third, discussed belowFootnote 27). The Special Rapporteur has devoted considerable attention to the other possibility, that of the possible effect of treaties (in general law) as evidence of opinio juris:Footnote 28 how might such effect operate in the specific context of human rights?

The Special Rapporteur has observed that, while a treaty or treaties may express a ‘juridical consciousness’, if this is to amount to opinio juris, then, whether it is ‘with regard to the convention as a whole or to certain provisions’, it:

must exist outside the treaty, not just within: for a treaty to serve as evidence of opinio juris, States . . ., whether parties or not must be shown to regard the rule(s) enumerated in the treaty as binding on them as rules of law regardless of the treaty.Footnote 29

The treaty can presumably therefore only act as confirmatory evidence of the existence of opinio juris. What seems clear is that one and the same treaty cannot constitute simultaneously evidence of opinio juris and state practice. Does the Rapporteur's finding need any amplification or qualification as regards human rights treaties?

Furthermore, acts by a party to a treaty subsequent to, and consistent with, the treaty must be taken to have been performed pursuant to the treaty, and thus cannot constitute practice in support of an asserted customary rule.Footnote 30 Alan Boyle and Christine Chinkin have studied closely the role of human rights treaty bodies, and suggest that ‘the various instruments and opinions issued by the human rights committees are often cited, and may well be viewed as a form of soft law’, the repetition of which creates ‘a consensus that a lawyer would be foolish to ignore’.Footnote 31 The authors do not argue that law created by consensus in the more formal sense (as a method of adopting shared decisions) creates a form of customary law eo nomine, but rather that ‘securing widespread support’ for a text so adopted ‘not only legitimises and promotes consistent state practice but makes it less likely that other states will object to immediate application. New customary law may come into being very quickly by this method’.Footnote 32 It seems then that ‘consensus law-making’ in this field is no more than a catalyst enabling the usual processes of custom formation.

Much discussion seems to be based on the idea that what matters is to establish that, for example, participation in human rights treaties constitutes law-formative practice, on the (generally unstated) premise that opinio juris is evident: everyone agrees that human rights need to be protected in law. Thus the Restatement Third has a separate section on ‘practice accepted as building customary human rights law’,Footnote 33 which includes ‘virtually universal participation of states in the preparation and adoption’ of human rights treaties.

A similar argument is to the effect that certain provisions of the Charter, or of the Universal Declaration of Human Rights, which were, at most, effective as a matter of treaty law, have ‘become’ customary law, or ‘may be deemed to have become customary law’. If this means that such provisions are evidence of opinio juris, and have become backed by state practice of the kind generally required, this again is a view which is perfectly compatible with the current approach of the Rapporteur. However, it seems that for some scholars, there is more to it than that. It has been argued in respect of ‘international instruments which would not usually be categorised as human rights treaties’ that ‘it is not inconceivable that these texts may themselves establish international obligations for states parties to guarantee human rights protection in a particular context’.Footnote 34 Are these then quasi-treaty obligations, or some specialised form of custom?

4. The relationship between opinio juris and state practice

The Special Rapporteur has in his Draft Conclusions already made an important distinction, namely between forms of practice (Draft Conclusion 6) and evidence of acceptance of law (Draft Conclusion 11). The two-element theory necessarily implies that there has to be something present that can be described as state practice, and something present that indicates, or from which the conclusion can be drawn, that states consider that a rule of customary law exists. There may well be an overlap between the ‘manifestations of practice’ and the ‘forms of evidence of acceptance’ of such practice as law; generally, this does not mean that given acts can constitute both, as that would amount to a return of the single-element theory.

But in the specific context of human rights is this too restrictive a view? Even in the classic paradigm of state practice adding up to custom-formation, the opinio juris may be apparent, at least in part, from the very acts constituting a practice. Since, as suggested above, that sort of basic custom-formation, by the resolution of colliding state interests, is virtually non-existent where human rights are concerned, is an extensive adoption of this approach justified? It is tempting to say, for example, that state participation in, or specific acceptance of, for example, the Universal Declaration of Human Rights, can be regarded both as showing a view (opinio) that those rights are or should be backed by legal norms, and as acts of practice, thus adding up to custom formation. While that may be the single-element heresy, could it be that acceptance of the Declaration, added to subsequent more specific statements of acceptance,Footnote 35 could add up to a legal commitment even if neither act were strictly classifiable as ‘practice’?

Some forms of what has come to be known as ‘modern’ customary law tend in this direction. A very extensive survey of academic writings on this subject is found in the (generously footnoted) part of the First Report devoted to ‘Writings’.Footnote 36 For example, one version of this approach does not go so far as to deem the ‘practice element’ of custom wholly superfluous in human rights matters; the contention is simply that ‘state ‘practice’ in the sense of ‘behaviour’ is less determinative than authoritative statements made by governments or intergovernmental bodies’.Footnote 37 As explained by Roberts:

Traditional custom is evolutionary and is identified through an inductive process in which a general custom is derived from specific instances of state practice . . . By contrast, modern custom is derived by a deductive process that begins with general statements of rules rather than particular instances of practice.Footnote 38

This however raises the question: what makes a statement of rules ‘authoritative’?Footnote 39 And why, if a resounding multinational statement in other fields of law could only constitute evidence of opinio juris and not practice, should the legal situation be otherwise in human rights matters?

However, it is not here proposed to try to answer the question whether some human rights having the force of ‘law’ in inter-state relations may be validly derived from non-traditional ‘sources’. It is simply whether the ILC study of the formation of custom can afford to leave them aside, as being (whatever else they are) not ‘custom’ in any meaningful sense; or whether, on the contrary, a study of custom-formation that does not recognize the process giving rise to these rights would be incomplete in its intended definition of the formative process. That said, it should not be overlooked that any rights claimed to exist in international law should be capable of being linked to some recognized source: if neither treaty law nor ‘general principles of law’ afford a basis for an asserted recognition of a human right, then only custom remains – though perhaps custom with a special ‘flavour’.

5. A special kind of state practice? Acts and statements

It is of course possible to concede that both opinio juris and practice are needed to establish a customary rule of human rights law, but to hold that each element, but particularly practice, in this special domain may be of a different character from that generally required to establish a custom. A prominent document in this respect is the commentary on the Restatement (Third) of the Foreign Relations Law of the United States, Section 702 of which states that ‘A state violates international law if, as a matter of state policy, it practices, encourages, or condones . . . a consistent pattern of gross violations of internationally recognized human rights’.Footnote 40 The commentary treats separately the formation of custom in general and human rights law. Under the latter heading it states that:

Practice accepted as building customary human rights law includes: virtually universal adherence to the United Nations Charter and its human rights provisions, and virtually universal and frequently accepted acceptance of the Universal Declaration of Human Rights, even if only in principle; virtually universal participation of States in the preparation and adoption of international agreements recognizing human rights principles generally, or particular rights; . . .

As to statements having some official status,Footnote 41 can one draw a conclusion on custom-formation from a statement or statements evidencing opinio juris, and another statement or statements of such a nature that they can be treated as acts of practice? And can any given statement play either role? The Special Rapporteur rejects a distinction, offered some years ago, according to which opinio juris may be evidenced by statements generally indicating support for a particular norm, but a statement may only count as state practice if it is made in the context of matter in which the interests of the state making it are involved.Footnote 42 In view of the importance in the human rights field of ‘verbal acts’, and the tendency of states in that respect to say one thing and do another, might this distinction be re-examined in the present context? In any event, clearly the same statement, or group of statements, cannot play both roles. If it is correct that a treaty is an act of practice, but cannot at the same time be sufficient in itself to show opinio juris;Footnote 43 this is presumably also the case, a fortiori, for statements without a treaty law nature. Furthermore, is mere accumulation of similar statements enough,Footnote 44 or must they be clearly of two distinct classes, opinio-statements and practice-statements? If so, how are they to be distinguished?

The Rapporteur's Draft Conclusion 6(2) includes, as one of the ‘forms of practice’, the decisions of national courts, which may also be regarded as ‘verbal acts’, but ones clearly directed to a specific issue. These are not specifically mentioned, in the human rights context, by the Restatement (Third). Clearly, decisions enforcing human rights on the basis of national law are not here to the purpose; it is only if the national court relies on international law that its decision can constitute an act of state practice. Furthermore, since most breaches of human rights involve government action, the doctrine of state immunity usually stands in the way of any enforcement of human rights in the courts of a third state.Footnote 45 Hence the significance of the leading cases of Filartiga v. Pena-Irala,Footnote 46 in the US, and (as regards international crimes) Pinochet Footnote 47 in the UK, where the individual responsible for the breach of human rights was within the domestic court's jurisdiction, and international law was invoked.

Is there more to be said as to ‘consensus law-making’ – where does it fit into the classic schema of Article 38 of the ICJ Statute? If, despite its name, it is ultimately a form of customary law, then the present undertaking by the ILC would be incomplete without some account of it; but the same objection as was made above to Louis Henkin's ‘non-conventional law’ would seem to apply equally here. Or is it something grafted on to treaty law, as it were? Boyle and Chinkin argue that an instrument adopted by consensus may ‘stand the test of time and generate widely acceptable new law for parties and non-parties alike’.Footnote 48 But does it ‘generate’ new law simply by existing? Or do non-parties have somehow to adopt it in order for it to acquire binding effect? ‘New customary law may come into being very quickly by this method’, we are told, inasmuch as ‘widespread support for such a text not only legitimises and promotes consistent state practice, but makes it less likely that other states will object to immediate implementation’.Footnote 49 Is such a text then merely a catalyst enabling the usual processes of custom formation?

With regard to ‘modern customary law’ generally, there would seem to be a choice of three courses which the Rapporteur might put forward to the Commission:

  1. 1. If the view be taken either that modern customary law is no more than a doctrinal invention, or that whatever this modern law is, it is not customary law, and thus does not fall within the Rapporteur's mandate, then no more is needed than a statement to that effect, supported of course by argument, but unaccompanied by drafting suggestions.

  2. 2. If modern customary law can be regarded as not differing in principle from traditional law, but merely as a widening, in the special context of human rights, of the concepts of state practice, and/or of opinio juris, then that widening will presumably need to be discussed, and an attempt made to define its limits.

  3. 3. If modern customary law does not depend on the traditional two-elements, but is still to be treated, at least provisionally, as falling within the designation ‘customary law’, the present treatment in the Second Report of the formation of customary law will need to be supplemented.

6. Some questions for consideration

The following questions were offered as material for discussion and reflection; some were discussed at the workshop, others, for lack of time, left aside. The Special Rapporteur is now (March 2015) preparing his Third Report, in which he will no doubt take account of these questions to the extent (if any) that he finds necessary, to support or illustrate the Conclusions he puts forward. For the record, in the meantime, these were the questions listed:

  1. 1. Are human rights, or some of them, in practice protected by customary norms at the present time? If so, did those norms develop according to the traditional processes of custom-formation, or by some other process?

  2. 2. If the custom-formation process has been, or is becoming, different in respect of some or all human rights norms, in what does that difference consist? Assuming that general practice plus opinio juris is required, does the practice include elements (e.g. general statements) that would not normally be regarded as sufficient to establish customary law?

  3. 3. Do human rights treaties, bilateral or multilateral, have an influence on the development of customary rules that is more extensive than, or different in nature from, the generally recognized processes by which treaties influence custom?

  4. 4. It is generally accepted that human rights are rights erga omnes. Does it follow that the obligation to respect such rights is an obligation erga omnes? (i.e., if state A infringes the human rights of individual B, is that a breach of an obligation towards omnes, including, e.g., state C, even though B is not a national of, and has no connection with, C?)

  5. 5. Is there a distinction to be made, as a matter of customary law, between the legal situation resulting from ‘gross and large-scale violations of human rights’, and that resulting from infringement of lesser rights, particularly as regards the range of reactions available to other states?

  6. 6. Could or should the Commission, under its present mandate, examine the question whether the protection of human rights afforded by current international law (in particular, international conventions) is sufficient, and make recommendations?

7. Afterword

Reference was made in this article to the then forthcoming Third Report of Sir Michael Wood for the ILC on ‘Indentification of Customary International Law’, and it was observed that the Rapporteur would no doubt take account of the questions raised in this article ‘to the extent (if any) that he finds necessary’. The Report was published on 27 March 2015 (UN Doc. A/CN.4/682), and it appears that no such reference was in fact found necessary.

References

1 M. Wood, First Report on Formation and Evidence of Customary International Law, UN Doc. A/CN.4/663 (2013) (hereafter, ‘First Report’); M. Wood, Second Report on Identification of Customary International Law, UN Doc. A/CN.4/672 (2014) (hereafter, ‘Second Report’).

2 The author would like to make clear that he is not a specialist in human rights law, and he welcomes comments or corrections from those who are.

3 With perhaps some inconsistency, the Special Rapporteur, however, argues that ‘artificially dividing international law into separate fields’ would ‘run counter to the systemic nature of international law’ (Second Report, supra note 1, 13, para. 28).

4 See First Report, supra note 1, para. 3.

5 See Henkin, L., ‘Human Rights and State “Sovereignty”’, (1995–1996) 25 Ga. J. Int'l & Comp. L. 31Google Scholar, 37; and the criticism of d'Amato, A., ‘Human Rights as Part of Customary International Law: A Plea for Change of Paradigms’, (1995–1996) 25 Ga. J. Int'l & Comp. L. 47–49Google Scholar.

6 E.g., Bleckman, A., ‘Zur originären gewohnheitsrechtlicher Menschenrechtsnormen’ in Menschenrechtschutz durch Gewohnheitsrecht: Kolloquium 26–28 September 2002 Potsdam (2002), 38Google Scholar ff.

7 E.g. Corfu Channel case (United Kingdom v. Albania), Merits, Judgment of 9 April 1949 [1949] ICJ Rep. 22.

8 First Report, supra note 1, at para. 19.

9 Second Report, supra note 1, at para. 28 (footnotes omitted), and ibid., at 66, Draft Conclusion 10, requiring the existence of opinio juris. Some doubt may however be felt about the reason given for insistence on the two elements: ‘Any other approach risks artificially dividing international law into separate fields, which would run counter to the systemic nature of international law’; ibid., at para. 28.

10 With the possible exception of the prohibition of genocide: in the Reservations to the Genocide Convention case, while the ICJ did not use the term ‘customary law’, it described the ‘underlying principles’ as ‘recognized by civilized nations as binding on States, even without any conventional obligation’ (Advisory Opinion of 28 May 1951, [1951] ICJ Rep., at 23). The Court did not, however, base this on any analysis of formation of custom, but rather on the conception of genocide as ‘contrary to moral law and to the spirit and aims of the United Nations’ (ibid.).

11 Thus, e.g., R. Jennings and A. Watts, Oppenheim's International Law (2008) discusses the international protection of human rights without mentioning possible reliance on customary law; similarly N. Rodley in M. Evans, International Law (2014) devotes a section to ‘The Basis of Obligation in International Human Rights Law’ with no mention of customary international law; A. Aust, Handbook of International Law (2010), Ch. 11; P. Malanczuk, Akehurst's Modern Introduction to International Law, Ch. 14; etc.; A. Boyle and C. Chinkin, The Making of International Law (2007), play down the role of custom generally (21–22), but it is striking that on human rights their examination of law-making processes is essentially limited to treaty bodies (145–58). Contra, Brownlie, Principles of Public International Law (2003) (6th edition – the last edited by Brownlie himself), 537: ‘The vast majority of States and authoritative writers would now recognize that the fundamental principles of human rights form part of customary or general international law . . .’ (note the ‘or general’ however; general is not necessarily customary); and P. Dailler and A. Pellet, Droit International Public (1994), §286.

12 R. Wolfrum (ed.), Max Planck Encyclopedia of International Law (2012), Vol. IV, sub ‘Human Rights’, 1023–4, at para. 9.

13 See Second Report, supra note 1, at para. 15.

14 Ibid., 32, at para. 38.

15 First Report, supra note 1, 45–47, at para. 96.

16 For a recent contention that customary international law is ‘non-consensual’, see Guzman, A. and Hsiang, J., ‘Some Ways that Theories on Customary International Law Fail: A Reply to László Blutman’, 25 EJIL (2014), 555–6CrossRefGoogle Scholar.

17 For example, in customary law the existence of any recognized right of transit for land-locked states for access to the sea, now embodied in UNCLOS Art. 125, was very doubtful, presumably since such a right was only favourable to one group of states, and a burden for the other group; see, e.g., L. C. Caflisch, ‘Land-locked States and their Access to and from the Sea’, (1978) 49 BYIL, 71–100. Another indication is the official attitude of the US to the customary status of the rules as to diplomatic protection; this is said to have altered markedly when that state, from being generally in a plaintiff position, found itself increasingly in a defendant position: see J. Dugard, ‘The Future of International Law: A Human Rights Perspective’, in T. Skouteris and A. Vermeer-Künzli, The Protection of the Individual in International Law (Special Issue of the Leiden Journal of International Law, 2010), 4.

18 It has thus been argued that, in respect of ‘intrastate issues such as the human rights obligations, which largely protect citizens from their own governments . . . we need to broaden our understanding of state practice to include consideration of intrastate action (not just interstate interaction)’: A. Roberts, infra. note 38, at 777, who thereby appears to imply that the argument referred to is, at present, correct.

19 That of d'Amato, A., ‘Human Rights as Part of Customary International Law: A Plea for Change of Paradigms’, (1995–1996) 25 Ga. J. Int'l & Comp. L. 47–49Google Scholar. Buergenthal distinguishes modern human rights as rights of individuals, unlike those resulting from the protection of categories of persons in the first half of the twentieth century, and adds that to this extent, ‘human rights are no longer exclusively matters within the domestic jurisdiction of States’ (Max Planck Encyclopedia of International Law, supra note 12, Vol. 4, 1023, at para. 7; but what is that extent? See also the resolution of the Institut de droit international of 13 September 1989, preamble.

20 In this sense, see A. Cassese, International Law (2001), 370–2. Christian Tams has discussed the difficulty of applying the criterion of ‘important’ rights (employed by the ICJ in the Barcelona Traction case), and has referred to ‘the inherently vague and indeterminate notion of “importance”’, See C. J. Tams, Enforcing Obligations Erga Omnes in International Law (2005).

21 Judgment of 5 February 1970, [1970] ICJ Rep. 32, at 33. The Special Rapporteur has considered the question of obligations of jus cogens (and decided to leave it aside), but has not so far touched on any question of erga omnes obligations (see the mention by the Secretariat in the First Report, supra note 1, at para. 11).

22 See the present writer's discussion of the point in The Law and Practice of the International Court of Justice: Fifty Years of Jurisprudence (2013), 1504–9.

23 See Domincé, C., ‘La contrainte entre États à l'appui des droits de l'homme’, in Hacía un Nuevo orden internacional y europeo, Estudios en homenaje al Professor Don Manuel Diez de Verlasco (1993), 261–72Google Scholar. In the case of Armed Activities on the Territory of the Congo, Judge Simma considered that the human rights treaties that had been relied on justified Uganda in claiming to protect persons not shown to have Ugandan nationality, inasmuch as those treaties established obligations erga omnes, but on this point he was a lone dissentient, the majority of the Court not accepting this view: see Democratic Republic of the Congo v. Uganda, Judgment of 19 December 2005, [2005] ICJ Rep. 348.

24 O. Schachter, International Law in Theory and Practice (1991), Ch. XV. He did however suggest that ‘practice’ (his quote-marks) and opinio juris could be looked for in international forums where human rights are discussed.

25 ECHR, van Anraat v. Netherlands, Decision on Admissibility, 6 July 2010, Application No. 65389/09, para. 88, cited in the Rapporteur's First Report, supra note 1, 37, note 178; the wording closely follows the dictum in North Sea Continental Shelf, Judgment of 20 February 1969, [1969] ICJ Rep., 41–42, at 72.

26 For example, the purposes of the UN Charter, specifically that of ‘promoting and encouraging respect for human rights’, relied on, for example by the ICJ in the Namibia case (Advisory Opinion of 21 June 1971, [1971] ICJ Rep. 57, at 131). There may be a question whether this provision could be adduced to prove an obligation on UN Members to respect human rights that have only come to be recognized in more recent years; can the Charter be read to contemplate ‘human rights’ that did not have even a theoretical existence at the time of its adoption? (See the observation of Judge Bork in Tel-Oren v. Libyan Arab Republic, 726 F2d 774 (DC Cir 1984), that the US Alien Tort Statute did not contemplate human rights, as the latter concept did not exist in 1789.) Is this a case of ‘evolving concepts’? (see Gaja, G., ‘The Protection of General Interests in the International Community’, (2014) 364 Recueil des cours 65Google Scholar, at 65–66).

27 Restatement (Third) of Foreign Relations Law of the United States (1987), para. 22.

28 Second Report, supra note 1, 54–57.

29 Ibid., at 55.

30 This is not of course to say that there may not exist a customary rule parallel to, and identical with, that stated in the treaty, as in the Military and Paramilitary Activities case (Nicaragua v. USA), Jurisdiction and Admissibility, Judgment of 26 November 1984, [1984] ICJ Rep. 424, at 73, and Merits, Judgment of 27 June 1986, [1986] ICJ Rep. 93, at 174).

31 A. Boyle and C. Chinkin, The Making of International Law (2007), 157.

32 Ibid., at 160. It should however be added that the authors indicate that ‘certain topics may be inherently unsuited to a consensus negotiation process’, because ‘these do not readily lend themselves to the package deal approach’, and these topics include ‘human rights and humanitarian treaties’ (ibid., 159).

33 Restatement (Third), supra note 27, §701, note 2: and see below, para. 22.

34 Pronto, A. N., ‘“Human-rightism” and the Development of General International Law’, in Skouteris, T. and Vermeer-Künzli, A., The Protection of the Individual in International Law (Special Issue of the LJIL, 2010)Google Scholar.

35 A particularly striking, and perhaps unexpected, form of custom-forming practice in the human rights field may be when such rights are invoked by a state as a defence to a claim, as in the case of claims for breach of an investment treaty: see, e.g., Suez, Sociedad General de Aguas de Barcelona SA v. Argentina, ICSID Case No. ARB/03/19, cited in E. de Brabandere, Investment Treaty Arbitration as Public International Law, (2014), 142–3.

36 First Report, supra note 1, paras. 98–100.

37 O. de Schutter, International Human Rights Law (2010), 52.

38 Roberts, A., ‘Traditional and Modern Approaches to International Customary Law: A Reconciliation’, (2001) 95 AJIL 757CrossRefGoogle Scholar, at 757, 758. Modern customary law is also said to be based on rational choice theory, as was (in the view of Posner and Goldsmith) traditional customary law also: ‘Understanding the Resemblance between Modern and Traditional Customary International Law’, (1999) 40 Virginia Journal of International Law 639Google Scholar.

39 In the special context of human rights, in particular, there is a whiff of circularity here: a statement may contribute to the appearance of a custom if it is authoritative, and it may be authoritative because it states what one wants to believe is the law.

40 Restatement (Third), supra note 27, 1987.

41 See the explanations and examples in the Special Rapporteur's Second Report, supra note 1, at paras. 37–41.

42 ‘Claims may be made in the widest of general terms; but the occasion of an act of State practice contributing to the formation of custom must always be some specific dispute or potential dispute’: H. Thirlway, International Customary Law and Codification (1972), 58; for the Special Rapporteur's dissent, see the Second Report, supra note 1, 18, at para. 37, where the sentence preceding the one just quoted is reproduced. This may have led to a misunderstanding: it was not, and is not here, suggested that, for example, a firm diplomatic note, addressed to the specific dispute, would not amount to state practice, even if matters remained on that level.

43 See section 3 above.

44 ‘What I tell you three times is true’: L. Carroll, The Hunting of the Snark, Fit The First, l, 8.

45 As recently confirmed by the ICJ in a case involving humanitarian law: Jurisdictional Immunities of the State (Germany v. Italy; Greece intervening), Judgment of 3 February 2012, [2012] ICJ Rep. 99.

46 630 F.2d 876, 878 (2d Cir. 1980). The US court had jurisdiction under the Alien Torts Statute, which requires that the action be for a tort ‘committed in violation of the law of nations’. In fact however the court did not cite any ‘usage’ of the traditional kind, but relied on the UN Charter, the 1975 UN Declaration, and ‘numerous treaties and accords’. The Filartiga decision thus did not in fact invoke practice, but may itself be considered an act of state practice! See also Kadic v. Karadzic, 70 F.3d 232, 236–37 (2d Cir. 1995).

47 R. v. Bartle and Commissioner of Police for the Metropolis (Ex Parte Pinochet), 24 March 1999, [1999] UKHL 17.

48 A. Boyle and C. Chinkin, supra note 31, 159. It should however be added that the authors indicate that ‘certain topics may be inherently unsuited to a consensus negotiation process’, and these include ‘human rights and humanitarian treaties’ (ibid.)

49 Ibid., at 160.