1 Introduction

‘In a divided world, the concept of the rule of law is one of the greatest unifying factors, perhaps the greatest, the nearest we are likely to come to a universal principle.’Footnote 1

International legal order—in a greater scale than its national counterparts—must constantly defend and reassert its foundational, structural, institutional and operative elements against external assailants and internal heretics. Some claim that during the past decade the contestations have ascended to a new level and may challenge the core integrity of the international legal order.Footnote 2 Similar claims pertaining to the disruption of the unity of international legal order have infiltrated mainstream scholarship since the early 2000s.Footnote 3 Is it possible to identify some foundational elements of international law that can be generally accepted by all States? Can such core elements reach a normative threshold to be considered requirements rather than “values” or “virtues”Footnote 4? And finally, what are these core requirements of the international rule of law?

This contribution propositions that, indeed, such core elements exist, identifies them from practices of States at the international level and conceptualises them as the minimum requirements of the international rule of law. The strength of the contribution lies not so much in the outcome of the identification and dissection of these requirements but in the methodological exercise of analysing State (verbal) practice with the support of relevant jurisprudence. While some theorising has gone into defining the international rule of law,Footnote 5 instead of the pie-in-the-sky approach this contribution presents an empirical study of statements of governments at the United Nations (UN) during a five-year period (2012–2017), accompanying the relevant findings with references to decisions and opinions of the International Court of Justice (ICJ). At the same time, neither the empirical material itself—what governments and judges say—nor its analysis are devout of normative content. On both levels, it is transparently maintained that the international rule of law and its elements—regardless of disagreement on their content—are essential and desirable features of a well-ordered international system. Nonetheless, the crux of this contribution is not in reinventing the normative but exploring and exposing the empirical. The author adopts (if conventional) normative assumption that the international rule of law is worth defending and advancing but such endeavour ought to follow what the main subjects of international law—the States—do and say.

In his landmark book on the rule of law, Tom Bingham suggested that ‘[i]f the daunting challenges now facing the world are to be overcome, it must be in important part through the medium of rules, internationally agreed, internationally implemented and, if necessary, internationally enforced. That is what the rule of law requires in the international order.’Footnote 6 Yet in political parlance at the UN one often hears that ‘[the rule of law] is an extremely broad concept that has no consensual definition or scope agreed upon by the [United Nations] Member States’.Footnote 7 Although ‘in recent years, the importance of the rule of law in world affairs has been recognized on an increasingly frequent basis by the international community’,Footnote 8 its substance remains disputed, for ‘there are almost as many conceptions of the rule of law as there are people defending it’.Footnote 9 Hence, ‘as blanket term … “the rule of law” appears to be overused, of limited analytic or descriptive value, and potentially distorting’.Footnote 10 It would appear that the trepidation of the rule of law as a Trojan horse to import substantive goals, as depicted by Simon Chesterman in 2008, has materialised. Therefore—and serving as the general objective (and warning!) of this contribution—conceptual clarity is essential in unfolding what lies at the core of international rule of law. The aim is to respond to the overuse of the blanket term on one hand and to restore its analytical and descriptive value on the other, if in a limited capacity, and accepting that this is but one attempt: ‘[t]here may not be one single definition for the rule of law, but there are certain core elements that we can identify.’Footnote 11

This contribution argues that non-arbitrariness, consistency and predictability form the core minimum requirements of the rule of law, which are acceptable for all States. The first section explicates the contour of the understanding of the ‘rule of law’ and engages with some relevant literature dedicated to the international rule of law. The second section introduces the notion of the rule of law and international rule of law at the United Nations. The third section then shows how the core requirements have been identified through the UN rule of law debates and expressed by States in the General Assembly (UNGA). These findings are discussed in relation to relevant ICJ jurisprudence. Building on this, the final section draws some conclusions from the findings and demonstrates why it is crucial to foster conceptual clarity in discussing the international rule of law.

2 Defining the International Rule of Law

The international rule of law has not developed in a vacuum: its conceptual roots, practices and reflections in judicial decisions inevitably draw from the notion of the rule of law at the national level.Footnote 12 Nevertheless, it has been accurately argued that the domestic rule of law concept, its content and meaning cannot be simply transposed, implemented or internalised at the international level for various reasons: the horizontal hierarchy of actors, de-centralised law-making, lack of effective judicial review mechanisms, and pluralist notions of justice, to mention just some.Footnote 13 The rule of law and the international rule of law are two distinct concepts, which evolved in response to different sets of issues and problems.Footnote 14 Therefore, I provide a very brief overview of central doctrinal positions in the general rule of law debate and the interfaces between the two concepts, before proceeding with the focus on the international rule of law and its core requirements.

According to Sir Arthur Watts, national understandings of the rule of law are at best an approximate guide to the content of their international analogue.Footnote 15 In this view, many elements of the rule of law at the national level are simply not equivalent for the purposes of the international legal order. His reasoning stems from the specific requirements of the rule of law in the domestic contexts, often reflective of a State's particular historical and constitutional evolution. While the rule of law at the national level may focus legitimately on the protection of rights of the individual against the State, the rule of law at the international level is primarily concerned with the coordination of inter-State interactions.Footnote 16 James Crawford has expressed the view that the international rule of law as an analogue to the domestic concept is conditioned by certain facts, notably the absence of legislative power such as it exists in domestic legal systems, and the correlative need for many decisions to be made by consensus of the States.Footnote 17 For similar reasons, Hisashi Owada calls for a reconceptualization of the rule of law in the international context, even though certain elements of the rule of law remain so essential that they should be applicable in interstate relations as they are in the domestic realm.Footnote 18

The international rule of law has purposes beyond limiting arbitrary use of power.Footnote 19 Due to the lack of vertical power paradigm in international relations, the international rule of law purports to regulate relations—whether or not consisting of exercise of authority– between actors. Machiko Kanetake has classified these relations as ‘horizontal state-to-state relations, authority exercised by the government against individuals and non-state entities, and authority exercised by international institutions’.Footnote 20 She also provides a sketch of specific national and international rule of law elements with an aim similar but methodologically contrasting to the present study. Kanetake approaches the elements of the international rule of law by taking ‘major rule of law elements adopted at the national level [as analytical support], and see[ing] if they can be found in international legal practices’. Relevant is also her acknowledgment of non-substantive qualities of the law, ‘such as non-retrospectivity, openness, and certainty of law’, with a reference to Joseph Raz.Footnote 21

At the current point in time in the evolution of international law, it is no longer necessary to transpose, implant or utilise domestic rule of law notions in order to find the international rule of law. This does not negate the fact that many of these concepts are nonetheless deeply rooted into political philosophy and command our thinking of any legal or political system. The issue concerns more the starting premise of discussion: are we looking to find concepts or requirements predetermined by domestic settings (or our thinking about them) or are we willing to see what concepts emerge in the international legal order?

While classically international lawyers have viewed the system through their domestic monocle, such restraint should be set aside, taking a fresh look at international law, and in this context, carving out the core notion of the rule of law at the international level, which attracts universal acceptance.Footnote 22 While vouching for international international legal scholarship free of national conceptual constraints, I acknowledge the irony in looking at statements of States to find the core of international rule of law. This, in my view, however, does not pose an oxymoron but rather a restatement of classic international law doctrine: I argue that we cannot accurately identify rules (primary, secondary, meta) of international law by looking at what States say and do at home but rather through their actions and statements at the international level. It is through those actions and statements that States interact with and—intentionally or inadvertently—shape international law. As Brian Tamanaha has persuasively argued:

[i]f there is to be an enduring international rule of law it must be seen to reflect the interests of the entire international community. Otherwise there is little prospect of pervasively entrenching the requisite belief that international law is worthy to rule.Footnote 23

At the international level, the commitment of States to the minimum requirements of the international rule of law extends to meta-normative level but can be found in solid (verbal and physical) practice without embracing an ethically thick concept.Footnote 24 This contribution approaches the core of the international rule of law as a set of requirements illustrated and identifiable in legal (argumentative) practice and semantics (even if presented in a politically charged forum). Adopting a pragmatist approach converging the normativity of law from social facts and practices allows one to identify shared understandings, which in turn can set parameters for criteria of legality, which form (core) of the international rule of law.Footnote 25 Here, engagement with the practice-focused conception of the rule of law goes on to show States’ general acceptance, through (verbal) practice, of these core requirements. The core requirements of the international rule of law are not a part of ordinary legal rules. They serve a normative function broader, deeper and higher than the primary or secondary rules of international law and could be construed in a sense of an international rule of recognition.Footnote 26 In this contribution, the focus is grounded on unveiling these requirements and while transparently siding with positivist understanding of law, the discussion on Hartian international rule of law—however compelling—will be left for another day.

A meaningful definition capable of underlying the international legal order thus needs to be able to justify itself to the legal subjects. Since States continue to be the primary subjects of international law, their legal opinions and practices need to be assessed in order to identify these distinguishing features. Yet I am not vouching that the requirements of international rule of law be based on full, universal and explicit consent of States but a general acceptance, which is neither controversial nor broadly contested. At the international level, we can identify a ‘modest rule of law’Footnote 27––and to foster and build on its resilience we must exercise analytical cautiousness in avoiding substantive overreaching. While the views expressed by States serve as the starting point for identifying these requirements, judicial decisions and academic writings are highly relevant as subsidiary means for their further interpretation and rationalisation.

3 International Rule of Law in the UN System

The normative foundation of the international rule of law in the UN framework is embedded in the Charter of the United Nations.Footnote 28 The Preamble of the Charter expresses the determination of the founding Members of the Organization ‘to establish conditions under which justice and respect for the obligations arising from treaties and other sources of international law can be maintained’.Footnote 29 In the UN instruments, the term ‘rule of law’ first appeared in the Universal Declaration of Human Rights of 1948, the preamble recognising ‘… human rights should be protected by the rule of law …’.Footnote 30

The question of the rule of law as a legal concept and as a political idea is reflected throughout the debates at the UN, which explicate the pendulum between the ‘thin’ and the ‘thick’ definitions,Footnote 31 and both process-oriented and substantive elements are regularly discussed.Footnote 32 In 2004 the concept was given substance when the Secretary-General defined the rule of law as

a principle of governance in which all persons, institutions, and entities, public and private, including the State itself, are accountable to laws that are publicly promulgated, equally enforced and independently adjudicated, and which are consistent with international human rights norms and standards. It requires, as well, measures to ensure adherence to the principles of supremacy of law, equality before the law, accountability to the law, fairness in the application of the law, separation of powers, participation in decision-making, legal certainty, avoidance of arbitrariness and procedural and legal transparency.Footnote 33

With the benefit of hindsight, this thick definition was perhaps an overreach on the part of the Secretary-General, or it may not have been intended to be taken as a holistic reference point. At the same time, it speaks to the rule of law at the national level rather than providing an insight into what may lie at the core of international rule of law.Footnote 34

While no formal definition of the rule of law had been agreed upon by Member States, the discussions began to gain momentum after the 2005 World Summit.Footnote 35 The normative relevance of the rule of law was becoming recognised as ‘an increasingly relevant reference point against which the behaviour of states is assessed under international law’.Footnote 36 The World Summit Outcome highlighted the need for ‘universal adherence to and implementation of the rule of law at both the national and international levels’Footnote 37 and reaffirmed Member States’ commitment to ‘an international order based on the rule of law and international law.’.Footnote 38

In September 2012, the General Assembly held the High-level meeting on the rule of law at the national and international levels. In the resulting Declaration,Footnote 39 the Member States reaffirmed their ‘solemn commitment to the purposes and principles of the Charter of the United Nations, international law and justice, and to an international order based on the rule of law, which are indispensable foundations for a more peaceful, prosperous and just world.Footnote 40 Although previous drafts of the High-level declaration repeated the definition of the rule of law as set out in the 2004 Report of the Secretary-General,Footnote 41 on the final text the Member States failed to agree on a definition of the rule of law due to conflicting political interests and protective attitude over aspects that––many considered––may impair State sovereignty and national ownership.Footnote 42 States also avoided using language implying that the rule of law is a binding principle of international law, and rededicated themselves ‘to support all efforts to uphold the sovereign equality of all States, to respect their territorial integrity and political independence…’Footnote 43 and recognising ‘the importance of national ownership in rule of law activities’.Footnote 44

Paragraph 2 of the High-level Declaration contains those general definitional parameters that the membership could agree on:

We recognize that the rule of law applies to all States equally, and to international organizations, including the United Nations and its principal organs, and that respect for and promotion of the rule of law and justice should guide all of their activities and accord predictability and legitimacy to their actions. We also recognize that all persons, institutions and entities, public and private, including the State itself, are accountable to just, fair and equitable laws and are entitled without any discrimination to equal protection of the law.

Equally noteworthy is to recognise what was left out of that paragraph, namely, any reference to human rights, separation of powers, participation in decision-making, and procedural and legal transparency.Footnote 45 Although the pursuit for a clear, universally acceptable definition of the international rule of law proved to be hopeless during the 2012 High-level Meeting and the Declaration, the statements delivered during the High-level meeting and, importantly, in the subsequent rule of law debates in the Sixth Committee of the UNGA shed light into understanding of how States perceive the international rule of law and its core requirements. The definition (or lack thereof) of the international rule of law was a topic of a heated debate also during the post-2015 process leading up to the 2030 Agenda and the Sustainable Development Goals. Given the particular scope in the context of development, the analysis of this debate falls outside of this contribution and has been discussed at length elsewhere.Footnote 46

4 UN Rule of Law Debates from 2012 to 2017

This summary study is thematically rather than chronologically organised, as many States stress the same points in each annual statement. The next subsections illustrate the overall support for the core requirements of the international rule of law but do not present a quantified analysis of each and every statement by all States during the five-year period. It is noteworthy that at the GA States usually omit delving into conceptual questions and have a limited allocated time to explain the meaning and context of their positions. In conducting an analysis of this kind one should not be too hasty or incautious in ascribing positions to States but rather keenly to scrutinise whether statements are intended to carry merely political or also some legal impetus. Still, if there is one public, multilateral, forum where States can be expected to voice their genuine concerns, views and positions, it is that of the UN General Assembly. While I am not making a claim that the General Assembly, its resolutions, or practice of States in the General Assembly would constitute law or have law-forming qualities beyond being affirmative of lex lata or on occasion reflecting lex ferenda,Footnote 47 it has been authoritatively noted by the International Law Commission that practice contributing to the formation of rules of international law ‘may take a wide range of forms’.Footnote 48 In this context, it is acknowledged that State practice includes conduct in connection with resolutions adopted by an international organization. This is not to suggest that the requirements of international rule of law identified here would necessarily form a part of customary international law, but that possibility is not excluded either. It would require, however, assessment of further evidence and with somewhat of a different approach to the one adopted in the current study, in order to determine the actual existence and extent of State practice and its acceptance in the form of opinio juris.

The following analysis also discusses the jurisprudence of ICJ, with the underlying assumption that judicial practice is aimed at authoritatively recognising sources and legal rules, and that the resulting decisions and opinions reflect international practice for the purposes, here, of identifying the requirements of international rule of law. ICJ, as the principal judicial organ of the UN,Footnote 49 is the only standing international court of a universal character with general jurisdiction.Footnote 50 Even though numerous separate and dissenting opinions of judges at the ICJ have referred to the (international) rule of law,Footnote 51 only three majority decisions mention the rule of law and offer an insight into the understanding of the concept by the Court. Decision of some regional courts are also referred to on occasions where they have directly addressed a point under discussion.

4.1 Non-arbitrariness

Since 2012, the Movement of Non-Aligned States has consistently demanded that the international rule of law must be anchored in the principle of sovereign equality.Footnote 52 As this Movement consists of 120 States its concerns shall be taken seriously, especially since many Non-Aligned States have in addition declared in their individual capacity that sovereign equality constitutes the basis of the international rule of law.Footnote 53 Furthermore, 33 CELAC States,Footnote 54 the Russian Federation,Footnote 55 Canada, Australia and New Zealand,Footnote 56 the five Nordic countries,Footnote 57 as well as ChinaFootnote 58 have explicitly expressed their support for sovereign equality as central in the rule of law discussions. Sovereign equality is closely related to the core requirement of non-discrimination.

The rationale behind this demand for the respect of sovereign equality of the States appears to lie in an understanding that the rule of law is the opposite of rule of power,Footnote 59 and politicization has to be avoided.Footnote 60 The international rule of law should protect against the unilateral imposition of values.Footnote 61 In order to avoid the claim that ‘might makes right’,Footnote 62 the international rule of law functions as the great equalizer among States,Footnote 63 so that equality before international law can be achieved.Footnote 64 Therefore, the norms of general international have to be agreeable to allFootnote 65 and reflect a true universal consensus,Footnote 66 while–with some reservations–upholding fundamental human values.Footnote 67 As a result, the debates in the Sixth Committee point to an understanding where non-arbitrariness constitutes one of the core elements of the international rule of law.Footnote 68

In the Colombian-Peruvian asylum case, the ICJ contrasted the rule of law with arbitrary political actions with the rule of law when it stated:

In principle, therefore, asylum cannot be opposed to the operation of justice. An exception to this rule can occur only if, in the guise of justice, arbitrary action is substituted for the rule of law. Such would be the case if the administration of justice were corrupted by measures clearly prompted by political aims.Footnote 69

ICJ further elaborated this point in the Elettronica Sicula S.p.A. (ELSI) (United States of America v. Italy) judgment:

Arbitrariness is not so much something opposed to a rule of law, as something opposed to the rule of law. This idea was expressed by the Court in the Asylum case, when it spoke of “arbitrary action” being “substituted for the rule of law” (Asylum, Judgment, I.C.J. Reports 1950, p. 284).Footnote 70

ICJ then defined arbitrariness as a wilful disregard of due process of law, an act which shocks, or at least surprises, a sense of juridical propriety.Footnote 71 ICJ’s understanding of non-arbitrariness as an element of the international rule of law appears to demand that any relevant exercise of power under international law requires a sufficiently legitimate basis in order to be justified. In this sense, it can be said that the restriction of arbitrariness as a core element of the international rule law is reflected in the jurisprudence of the ICJ.

4.2 Predictability and Consistency

Consistency bestows a certain conception of rationality to law and makes it more intelligible and thus predictable for the subjects.Footnote 72 Therefore, consistency and predictability are interlinked and taken together for the purpose of the present analysis. In the words of Judge Sir Robert Jennings, ‘[l]aw develops by precedent, and it is that which gives it consistency and predictability’.Footnote 73

In the Sixth Committee, CELACFootnote 74 and ASEANFootnote 75 have put much emphasis on the predictability of rules of international law as an element of the international rule of law. Additionally, Austria,Footnote 76 India,Footnote 77 Slovenia,Footnote 78 Kenya,Footnote 79 Japan,Footnote 80 Islamic Republic of Iran,Footnote 81 Turkey,Footnote 82 Belarus,Footnote 83 United States of America,Footnote 84 Republic of Korea,Footnote 85 Ukraine,Footnote 86 and EstoniaFootnote 87 have made statements to the same effect. Similarly, Israel,Footnote 88 the African Group,Footnote 89 Canada, Australia and New Zealand,Footnote 90 and BangladeshFootnote 91 have associated legal certainty with the international rule of law. Likewise, the five Nordic Countries have stated that blurred legal situations would impede the international rule of law.Footnote 92 Therefore, at least 117 States have expressed the view that predictability or certainty is an element of the international rule of law.

Other statements point to the importance of consistency in the application of legal rules for the international rule of law. Especially, the Movement of Non-Aligned States has stated on numerous occasions that selectivity in the application of international is incompatible with the international rule of law.Footnote 93 This view has been shared by ChinaFootnote 94 and Poland.Footnote 95 Double standardsFootnote 96 and claims of exceptionalismFootnote 97 in the application of international law have been described as inacceptable and as promoting politicization of law.Footnote 98 Instead, a number of States have called for fairnessFootnote 99 and equalityFootnote 100 in international law. In this context, ASEANFootnote 101 and the African GroupFootnote 102 have described consistency as an element of the international rule of law.

The ICJ has discussed predictability and consistency together, as they may share similar identifiers and promote similar outcomes, without being the same, as conceptualised above. In the Continental Shelf (Libyan Arab Jamahiriya/Malta) case, the ICJ found that:

the justice of which equity is an emanation, is not abstract justice but justice according to the rule of law; which is to say that its application should display consistency and a degree of predictability; even though it looks with particularity to the peculiar circumstances of an instant case, it also looks beyond it to principles of more general application.Footnote 103

The requirements of ‘consistency and a degree of predictability’ are not deduced from ‘abstract justice’ (equity contra legem), but from a rule of (positive) international law, which requires the application of equityFootnote 104 (equity intra legem).Footnote 105 Unfortunately, the ICJ has not explained how it infers these requirements from that (positive) law.

In the Armed Activities on the Territory of the Congo case, Judge Elaraby issued a Separate Opinion, in which he explained that in the Continental Shelf (Libyan Arab Jamahiriya/Malta) case, the ICJ had intended to emphasise that there is a ‘general desire for consistency and stability in the Court’s case-law when the Court is dealing with legal issues which have been before it in previous cases’.Footnote 106

Even though the ICJ is not obliged to adapt its own interpretation to that of another judicial body, it has considered that it should nonetheless ascribe great weight to the pronouncements of other bodies that were established specifically for the purpose of supervising the application of norm in question. Thus, in the Ahmadou Sadio Diallo case the ICJ took due account of the interpretations of the other bodies in order to achieve the essential consistency of international law.Footnote 107 Similarly, Vice-President Ranjeva, and Judges Guillaume, Higgins, Kooijmans, Al Khasawneh, and Buergenthal found in their joint declaration in the Legality of Use of Force (Serbia and Montenegro v. Germany) case that ‘[c]onsistency is the essence of judicial reasoning. This is especially true in different phases of the same case or with regard to closely related cases.’ Any Court ‘must ensure consistency with its own past case law in order to provide predictability.’Footnote 108

In order to ensure predictability, the requirement of consistency commands that norms of international law should be given the same meaning in every given case as long as it is appropriate––even if different tribunals are called upon to interpret it.Footnote 109 This is a view shared also by other international courts. The International Criminal Tribunal for the former Yugoslavia has declared ‘that in the interests of certainty and predictability’, it ‘should follow its previous decisions, but should be free to depart from them for cogent reasons in the interests of justice’, such as when ‘the previous decision has been decided on the basis of a wrong legal principles.’Footnote 110 Similarly, the European Court of Human Rights (ECtHR) found a court that failed to develop a mechanism to ensue legal consistency to violate the principle of legal certainty and thereby, to act contrary to the rule of law.Footnote 111 Accordingly, in the case law of international tribunals also beyond the ICJ consistency and predictability are acknowledged as elements of the international rule of law.

Predictability has also a connection to non-arbitrariness. The Inter-American Court of Human Rights has repeatedly stated that rules of law interfering with the rights of other subjects must be so predictable as to provide an adequate protection against arbitrarinessFootnote 112––a view that can also be found in the practice of the ECtHR.Footnote 113

It should be noted that outside of courts, international law sometimes evolves through deviations, a prime example of this being customary international law. Nonetheless, for such deviations to crystallise into legal rules, their practice must become consistent. In this sense, it is the rules of change and rules of interpretation, which convey a sense of predictability on the normative developments.Footnote 114

4.3 Other Elements

At the UNGA, 76 States have identified accountabilityFootnote 115 and 16 States the fight against impunityFootnote 116 as an element of the international rule of law. Last but not least, 57 States have described human rights as an element of the international rule of law.Footnote 117

In addition, during the 2014–2017 sessions, 24 States suggested that transparency constituted an element of the international rule of law.Footnote 118 While in many separate or dissenting opinions, judges have stressed the desirability of transparency in the reasoning of decisions of the ICJFootnote 119 and other tribunals,Footnote 120 a general demand of transparency has not crystallised.

Similarly, the ICJ has not drawn any link between the international rule of law on the one hand, and accountability or the fight against impunity, on the other hand. Yet, the Trial Chamber of the International Criminal Tribunal for the former Yugoslavia proclaimed in the Erdemovic case that it was part of its mandate

to contribute to the settlement of the wider issues of accountability, reconciliation and establishing the truth behind the evils perpetrated in the former Yugoslavia. Discovering the truth is a cornerstone of the rule of law and a fundamental step on the way to reconciliation.Footnote 121

It appears that the fight against impunity serves a function for the international rule of law in certain fields but it has not evolved to a level yet where it transcends international law in general so it could be considered to form a core of the international rule of law. However, as Judge Cançado Trinidade has noted in a separate opinion, the struggle against impunity may correspond to the demands of the international rule of law, where impunity amounts to a violation of international legal obligations.Footnote 122

Although the ICJ has not explicitly taken up the proposition that human rights formed part of the international rule of law, it has nevertheless acknowledged a connection between non-arbitrariness and human rights. In the Ahmadou Sadio Diallo (Republic of Guinea v. Democratic Republic of the Congo), the Court held that ‘protection against arbitrary treatment lies at the heart of the rights guaranteed by the international norms protecting human rights.’Footnote 123 This view has also been accepted in the jurisprudence of the ECtHR.Footnote 124 It thus seems that despite not forming part of the international rule of law in their own right, international human rights standards are one of the ways in which the non-arbitrariness demanded by the international rule of law can manifest itself.

While the review of States’ verbal practice in the Sixth Committee has demonstrated that also ‘thick’ concepts, such as human rights, accountability and the fight against impunity are embraced by a non-neglectable number of States, the ICJ has been much more cautious. The focus on non-arbitrariness, predictability and consistency as elements of the international rule of law in the jurisprudence of the ICJ can be explained, however, by a desire to stick to a rather non-substantive definition of the international rule of law.

5 Concluding Remarks

What kind of international rule of law is generally supported by States? While several States have proposed a variety of ‘thick’ definitions, many have argued that there cannot be ‘no one size fits all’ model for the international rule of law. The core requirements of international rule of law should be generally accepted; they should not face broad contestation or have their fundamental nature often questioned. They provide stability and continuity, even when values and structures around them change and develop. Through a study of the rule of law debates in the General Assembly during a five-year period, I have identified non-arbitrariness, consistency and predictability as the core requirements of the international rule of law. This conclusion finds support in the jurisprudence of the ICJ. Similarly, if through a different methodological approach—by relying on the doctrine of pacta sunt servanda as enshrined in customary international law and as part of jus cogens—Robert McCorquodale has asserted that ‘two of the objectives of the international rule of law are legal order and stability, and equality of application’.Footnote 125

The review of State practice reveals that thin and procedural definition of the international rule of law—while generally accepted—is complemented by calls for more substantive elements such as human rights, fight against impunity and accountability. These may fall under the broader umbrella of the rule of law but to argue that they are core requirements would dilute the normative specificity and clarity of the meaning of the international rule of law.

This contribution—with the objective of identifying core requirements of the international rule of law through engagement in positivist methodology—does not incorporate lengthy discussion of aspirational themes, such as democracy or transparency, which are not firmly established in the basic structure of the international legal system or even the requisites of national legal orders.Footnote 126 This problematique is analogous to the expansion of human rights paradigm and its challenges: its core legal elements––which may, arguably, be seen as universally accepted––have become entangled with contrasting political aims, and ‘human rights’ has become interchangeable with ‘human rights law’.Footnote 127 For this reason, the ambition of this contribution has been to focus on the strict legal identification and limited usage of the notion of the international rule of law.

Focus on the core requirements of the international rule of law restricts the concept from becoming a catch-all category, it elevates the rule of law and separates its core essence from political, moral and other extra-legal considerations. The identification of these core requirements also suggests that the idea of international rule of law has concretised into a meaningful concept, which can be found through law, not only politics. Since Simon Chesterman in 2008 noted that ‘[a]t the international level anything resembling even this limited idea of the rule of law remains an aspiration’,Footnote 128 the international rule of law has become not just a catch word to justify any agenda and common parlance to be uttered by politicians at every turnFootnote 129 but a fundamental conceptual tool, alongside human rights, development and peace and security, which is here to stay—even if its substance is plagued with ‘persistent vagueness’.Footnote 130 The rule of law, as noted by the President of Cyprus at the 2012 High-level Meeting on the Rule of Law at the National and International Levels and quoted at the start of this contribution, can be the greatest unifying factor and the nearest we are likely to come to a universal principle, but only if its conceptual clarity is fostered by focusing on its core requirements and stripping off the value-laden extra trimmings.