1. On multicausal historical writing
The ‘historical turn’ in international legal scholarship led to more awareness of the manifold perspectives one can take on the history of international legal scholarship. Over the course of the twentieth century until today, international legal historians have produced divergent and competing narratives of the foundational disciplinary concepts. Among these accounts three have been particularly influential. One approach stresses the progressive formation of an increasingly dense net of normative rules on the international level, a second highlights the contributions of non-Western regions to the field, and a third points to the dark side of the use of international law as a tool by hegemonic powers deeply implicated in colonial crimes.Footnote 1
As this article will show, the history of the jus cogens doctrine as a normative concept in international law could be written along the lines of each of these three perspectives. First, traditionally, the codification of the jus cogens doctrine in the Vienna Convention on the Law of Treaties (VCLT) in 1968/1969 is regarded as a symbol for progress towards a more value-based international law after the Second World War brought forward, in particular, by Western international lawyers. Studies on the history of the concept stress that the rapporteurs of the International Law Commission (ILC), Hersch Lauterpacht, Gerald Fitzmaurice, and Humphrey Waldock, took up an idea developed by Alfred Verdross in the 1930s and included the concept in their reports on the law of treaties.Footnote 2 These accounts reflect a tradition of historical writing which emphasizes international law’s gradual evolution towards a more value-based and sophisticated international legal system.Footnote 3 Throughout the twentieth century, academics identified ‘tremendous progress’ as international law’s ‘dominant trait’,Footnote 4 and praised the development from a ‘law of coexistence’ to a ‘law of cooperation’Footnote 5 and to a ‘law of mankind’.Footnote 6 Often these scholars highlighted that a learning process of especially Western states led to a morally advanced system of legal rules on the international political level.Footnote 7 The idea that British rapporteurs in the ILC successfully pushed for the doctrine of jus cogens fits well into this picture.
Second, as a counternarrative, the non-Western contribution to the jus cogens doctrine has been emphasized. Jean Allain recently put forward that decolonization has been the ‘source’ of the legal concept. He stressed that the ‘new states’ successfully supported jus cogens in order to criticize the existing international law shaped by Western states.Footnote 8 For him the ‘legacy of the decolonization process in international law should be recognized as moving away from the European-based bilateralism of yesteryear and ushering in a recognition that there are communal interests which transcend the interests of any given state’.Footnote 9 This historical reading of the jus cogens concept is inspired by writings of the decolonization era, when scholars underlined the African, Indian or Muslim impact on the evolution of international legal rules.Footnote 10 In his recent celebrated book Mestizo international law Arnulf Becker Lorca demonstrates that in the nineteenth century the ‘periphery’ appropriated European international law according to its own political ideals and created an international law consisting of various influences.Footnote 11 According to Allain’s account, non-Western states not only contributed to the creation of the jus cogens doctrine but were the driving force behind the idea.
Third, as this article will demonstrate, the history of jus cogens can also be told as exposing the dark side of international law. Verdross’ writings were closely related to the German/Austrian fight against the Paris Peace Treaties during the inter-war years. Jus cogens was regarded as a helpful tool by which one could circumvent the obligations of the disliked ‘peace dictates’. This narrative can relate to writings which stress the potential instrumental use of international law for contestable ends. Wilhelm Grewe’s controversial Epochs of International Law claimed that, since the fifteenth century, eras of Spanish, French, British, Anglo-American, and Anglo-Soviet domination brought forth international legal rules which were structured in line with the interests of the leading hegemon.Footnote 12 Furthermore, more recent studies connect basic features of international law like the sovereignty doctrine,Footnote 13 international institutionalization,Footnote 14 and the history of the United Nations (UN)Footnote 15 to the colonial project pushed by Western states.Footnote 16 Understanding jus cogens as a vehicle to demolish the Paris Peace Treaties in the context of National Socialist revision policies provides a similar ‘dark side’ story.
Which of these alternative histories offers the most plausible account of the emergence of the doctrine? Was it a stronger value-orientation, the involvement of non-Western states or the critique of the Paris Peace Treaties which explains the evolution of the concept? While one could subscribe to either historical reading, this article draws from all of these perspectives when engaging with the history of the jus cogens doctrine. Instead of juxtaposing the divergent accounts against each other and claiming exclusive truth for one narrative, it takes the view that the history of jus cogens is complex and can be traced to different origins. Instead of constructing a straightforward monocausal story, it takes all three historical perspectives seriously.
This somewhat runs against a common trend in international legal scholarship which stresses the plurality of narrative(s)Footnote 17 and international legal historiesFootnote 18 and regards them as distinct and incompatible. Often authors assume that traditional perspectives and more critical perspectives which stem from the ‘turn to history’ cannot relate to each other. Indeed, if the recent critical approaches are written to deconstruct the earlier historical writing, how could one reconcile the positions? Furthermore, if no one can tell ‘how history really was’,Footnote 19 if historical works are closely related to fictionFootnote 20 and linked to the political preferences of the respective authors, why should one bother with ‘mediating’ different historical perspectives?
Nonetheless, this article takes a ‘mediating’ approach. Even though it is convincing that the reading and interpretation of history depends on our personal and present experiences and a certain narratological strategy is necessary to convey the historical argument to the reader, in the view of the author the openness for pluralist approaches to the history of international law does not justify the production of one-sided stories. International lawyers should be careful not to tell straightforward narratives of particular doctrines and neglect the manifold political contexts in which doctrines are applied to different usages. Accordingly, the article tells the history of the normative concept as a multicausal phenomenon. The jus cogens doctrine (i) stemmed from dark origins in the context of the inter-war period, (ii) reflected a development towards a more value-based international law starting in the 1920s which reached a first peak in the 1960s, and (iii) benefitted from the endorsement by non-Western actors during the Khrushchev era and in the context of decolonization.
This article thus underlines that jus cogens was used at different moments in time, by different actors, for different purposes. Because the political environment and the international legal system changed, new actors applied the concept from different vantage points to attack the governing status quo. In this sense, the different accounts follow a chronology from the German/Austrian fight during the inter-war period against the Paris peace system to the struggle of Third World states and the Soviet Union against traditional Western-centred international law after the Second World War. However, a strict chronological story does not do justice to the overlaps and tensions which existed between the different actors who pushed for the idea of jus cogens. During the 1920s, jus cogens was not only regarded as a tool against the Paris Peace Treaties but also as an expression of an international legal system based on values and natural law. After 1945 it was not only propagated as a tool to criticize Western international law but also as an emblem of Western promoted value-laden international law. By including these different perspectives in the historical account, the article embraces the complexity and multi-facetedness of the jus cogens doctrine’s origins.
2. Jus cogens as a tool to circumvent the Paris Peace Treaties
2.1. The German-speaking discourse
In retrospect, the jus cogens doctrine is sometimes traced back to the natural law writings of Francisco de Vitoria and Hugo Grotius.Footnote 21 Moreover, one has to note that some writers of the nineteenth century claimed that an international public order existed which has a superior status to treaty law.Footnote 22 Nonetheless, it seems that the terminology of jus cogens in international law (or zwingendes Völkerrecht) became particularly prominent in the discourse of German-speaking international lawyers during the inter-war period.Footnote 23
Switzerland was one location where some early conceptualizations of the idea evolved. A book on the morality of international treaties was published in 1924Footnote 24 and nine years later a first monograph on Zwingendes Völkerrecht was published at the University of Zürich.Footnote 25 While these two studies did not receive a lot of attention in the discipline, a parallel strand – generated in Austria around the same time – had a stronger influence on the general discussion. From the late 1920s to the mid-1930s, the famous Austrian international lawyer Alfred Verdross (1890–1980) slowly developed and disseminated his ideas about jus cogens. Verdross had become a professor at the University of Vienna in 1925 and soon dominated Austria’s international legal discipline alongside his colleague Hans Kelsen. In his Hague lecture of 1929, Verdross put forward the idea that international law contained ‘rules of “jus cogens” which oblige states to strictly observe a certain conduct’.Footnote 26 At the same time, Friedrich-August von der Heydte,Footnote 27 an assistant at Verdross’ Viennese chair, published an article about ‘ius cogens and ius dispositivum in international law’. Von der Heydte argued that several categories of jus cogens norms existed: rules which are indispensable for the existence of international law as a legal order and rules in which all members of the community have an interest.Footnote 28 In the mid-1930s, Verdross himself then engaged more intensively with the concept in two articles on ‘reviewable and void’ as well as ‘holy and immoral’ international treaties.Footnote 29
2.2. Declaring the Versailles Treaty null and void
The writings of Verdross were closely related to one of the main goals of German/Austrian international legal scholarship of the 1920s and 1930s: the revision of the Paris Peace Treaties. The German/Austrian discipline was preoccupied with the Peace Treaties of Versailles and Saint Germain, which sanctioned territorial losses of Germany and Austria and laid the basis for reparation claims against the countries. Based on broad scholarly consensus the academics devoted considerable energy to attacking provisions of the perceived ‘dictates’.Footnote 30 For Heinrich Triepel, the famous father of the doctrine of dualism, the clause prohibiting the reunification of Germany and Austria constituted an ‘unnatural separation’ that a ‘great nation’ could not tolerate permanently.Footnote 31 According to the Hegelian-minded Erich Kaufmann, it was ‘madness’ to base a peace treaty on ‘punitive justice’.Footnote 32 Not only national conservative thinkers, also many pacifists rejected Versailles. The Geneva professor Hans Wehberg described the revision of the Treaty as ‘a precondition for the reconstruction of Europe’.Footnote 33 For Walther Schücking, the German judge at the Permanent Court of International Justice (PCIJ), the Treaty resembled an ‘egregious injustice’ triggering a ‘right to revision’.Footnote 34
Also Verdross was highly sceptical of the Paris Peace Treaties. As a bourgeois Austrian nationalist, he believed in the unification of Austria and Germany which the treaties explicitly forbade. As he himself later emphasized, since 1918 he had propagated großdeutsche ideas.Footnote 35 Furthermore, he took a sceptical approach towards the international system installed by the League of Nations because it was related to the Paris Peace Treaties. For instance, he argued that the mandate system of the League disguised that through the Versailles Treaty the German colonies had been taken without compensation.Footnote 36
The idea of jus cogens was also developed as a tool to fight the peace treaties.Footnote 37 In his Hague lecture of 1929, Verdross indicated that a convention would be contra bonos mores and invalid if it did not allow a state to protect its subjects properly.Footnote 38 Shortly thereafter, in an article on the merger of Germany and Austria, he criticized the provisions of the Versailles and Saint Germain Treaties, which codified that Austrian independence ‘shall be inalienable, except with the consent of the Council of the League of Nations’. He underlined that immoral treaties are not valid according to international law.Footnote 39 Five years later, in the context of aggressive National Socialist revision policies, Verdross became even more outspoken. In March 1935, Adolf Hitler had deliberately set aside the Versailles Treaty’s limit of a 100,000-strong German army (Art. 160) by introducing military service by draft. Britain, France and Italy reacted by initiating a resolution in the League of Nations. On 17 April 1935, the Council of the League criticized German rearmament and stressed that the ‘scrupulous observance of all the obligations of treaties is a fundamental rule of international life and a primary condition for the maintenance of peace’.Footnote 40 Verdross attacked this statement in an extensive article. Pacta sunt servanda would only apply in case the treaties in question were valid.Footnote 41 The remainder of the article was devoted to criticism of the ‘Versailles Dictate’ using three arguments. First, Verdross put forward that the whole Treaty of Versailles was null and void because of illegal coercion. Many German international lawyers took the position that the treaty was illegally forced upon Germany after the end of the First World War as – threatened with further military action – Germany had had no choice but to sign.Footnote 42 Second, Verdross also criticized the treaty as breaching a preliminary peace treaty. German international lawyers put forward that Woodrow Wilson’s Fourteen Points had been the offer of a preliminary peace treaty, which Germany had accepted. This preliminary peace treaty had then been violated by the much stricter conditions imposed by the Treaty of Versailles.Footnote 43 To these well-known arguments, Verdross now added a third: the notion of immoral treaties. After stressing that ‘zwingende Völkerrechtsnormen’ would establish limits to the possible content of international treaties, he explained that the peace treaties would be a prime example of void international treaties. He underlined that the maintenance of internal and external security would belong to the ‘morally imperative functions of the state’. The peace treaties had to be regarded as immoral and void because they would strip Germany of the opportunity to defend itself against aggression from outside.Footnote 44
The political context of Verdross’ writing also becomes obvious in a vivid exchange with the notorious German lawyer Carl Schmitt. Schmitt, who during the early 1930s legitimized various aggressive National Socialist policies,Footnote 45 had published a study on National Socialism and international law. In this work, he criticized the ‘illusory boom of international legal scholarship’ during the League era. For him, the Viennese ‘pure theory of law’ provided the fallacious theoretical foundation for this optimism. Schmitt explicitly attacked Verdross for legitimizing the Versailles Treaty by putting a strong emphasis on the principle of pacta sunt servanda in his writings.Footnote 46 Indeed, in his famous Verfassung der Völkerrechtsgemeinschaft Verdross had declared the pacta sunt servanda principle to be one foundational principle of the international community.Footnote 47 However, Schmitt’s critique triggered a forceful reaction. In a footnote in his article on void treaties, Verdross built a line of defence. It was ‘unintelligible’ how Schmitt could arrive at his conclusions, even though all of Verdross’ writings would envision limitations for the pacta sunt servanda principle. He emphasized that he had always highlighted the possibility of declaring the ‘peace dictates’ void and that law was grounded in morality.Footnote 48
2.3. The doctrine travels
The idea of jus cogens slowly moved from the German-speaking world to the international plane. At first, the concept had hardly any influence on academic writing and legal practice.Footnote 49 In 1936, the British international lawyer James Brierly stated in his Hague Course that ‘the law imposes little restriction on the conditions which States may introduce in their treaties’. The migration of the idea of such limits from the domestic to the international level would be unlikely in the near future.Footnote 50 Also, the early mention of the concept by an international court – the separate opinion of the German PCIJ judge Walther Schücking in the Oscar Chinn case between Britain and Belgium of 1934 – largely went unnoticed. Interestingly, Schücking used the idea of jus cogens to argue that another treaty was void, which had been concluded after the First World War. At the heart of the Oscar Chinn case were the principles of free trade and freedom of navigation as laid down in the 1919 Convention of St. Germain which superseded the notorious Congo Act of 1885. While Germany had been a treaty party to the Congo Act, it had not taken part in the deliberations at St. Germain. Schücking argued that the St. Germain Convention was invalid because it violated the jus cogens established by the Congo Act.Footnote 51 Again, a German speaking lawyer used the jus cogens concept to criticize a post-First World War treaty.
With his famous American Journal of International Law (AJIL) article on forbidden treaties of 1937, Verdross then presented his idea of jus cogens to the wider world.Footnote 52 In reaction to a report on the law of treaties, which had been developed by the Harvard Research Group under the auspices of the American international lawyer James Wilford Garner,Footnote 53 Verdross criticized the report for not addressing the question of conflict between treaties and general international law. Referring to the early Swiss monograph on ‘Zwingendes Völkerrecht’, he stressed that, therefore, ‘the existence of ius cogens’ was at stake. According to Verdross’ view, jus cogens prohibited concluding immoral treaties and treaties contra bonos mores. For assessing whether a treaty was immoral, one had to ask whether a treaty allowed a state to fulfil its main moral tasks: the maintenance of law and order among states, defence against external attacks, care for the spiritual and physical well-being of citizens, and the protection of nationals abroad. More concretely, Verdross put forward that:
binding a state to reduce its police or its organization of courts in such a way that it is no longer able to protect at all or in an inadequate manner the life, the liberty, the honor and the property of men on its territory …
is forbidden in international law. Furthermore, he added that an ‘international treaty binding a state to reduce its army in such a way as to render it defenseless against external attacks’ was immoral. Concluding, Verdross proposed to integrate a norm into the Harvard treaty report which held: ‘A treaty norm is void if it is either in violation of a compulsory norm of general international law or contra bonos mores.’Footnote 54
The critique of the Paris Peace Treaties was less directly advanced in the AJIL article than in Verdross’ German writings, however, a skilled observer could sense the undertone. Verdross cited a work on the revision of the Paris Peace Treaties when explaining the concept of jus cogens.Footnote 55 Also his reference to the maintenance of a functioning military as a moral task of the state had to be understood against the background of German rearmament. Hence, even the AJIL article contained an ex post facto legitimation of Hitler’s aggressive revision policies of the Paris Peace Treaties.
This explains why the British international lawyer Hersch Lauterpacht at first reacted very sceptically to the concept of immoral treaties. In his 1937 Hague lecture he underlined, with explicit reference to the writings of Verdross: ‘The alleged nullity of immoral treaties is a constant invitation to those who violate the law, to unilaterally and heroically disengage themselves from the obligation which impedes them.’Footnote 56 Knowing the German discourse, Lauterpacht feared the political implications of the jus cogens doctrine. As a tool for criticizing the Paris Peace Treaties during the Weimar and National Socialist years, the jus cogens doctrine threatened the stability of international relations.
3. Jus cogens as a pierce to absolute state sovereignty
3.1. Relative sovereignty during the inter-war period
Besides this tainted legacy of the legal doctrine, the concept also stems from an intellectual tradition which many international lawyers regard as a positive development: the emergence of a more value-oriented international law which is based on higher moral principles and limits the sovereignty of states. Still, today some lawyers understand the doctrine as a foundational concept for the emerging international communityFootnote 57 or highlight the potential for enhancing the fairness of international law.Footnote 58 This strand of thought became particularly influential after the Second World War, emanating from the discourse of the inter-war period.
In the 1920s, some Western jurists had attacked the doctrine of state sovereignty and the dominating theory of voluntarism according to which all legal rules had to be based on the consensus of states. In the context of the establishment of the League of Nations, authors from across Europe and the United States propagated the idea that international institutions and international law had to be taken seriously and decried the concept of absolute state sovereignty. Well-known academics like Nicolas Politis, Edwin Borchard, James Brierly, George Scelle and Paul Fauchille promoted turning away from the traditional consensus-based understanding of international law.Footnote 59 In the German-speaking world, Hans Kelsen, Walther Schücking and Hans Wehberg subscribed to the project of international institutionalization and developed theories fighting against the sovereign state dogma. By pointing to the advantages of the League and international co-operation, they criticized traditional voluntarist conceptions of the pre-war period.Footnote 60 For some observers, international law appeared to be in an era of transition and transformation.Footnote 61
Not only progressive modernizers embraced these ideas but also more conservative thinkers. In his inaugural essay on the founding of the Berliner Kaiser-Wilhelm Institute for Comparative Public Law and International Law, Viktor Bruns expressly dissociated himself from a PCIJ opinion, in which the judges had emphasized that the principle of the independence of states was a basic principle of international law.Footnote 62 Bruns argued instead for the existence of an international legal community: ‘The basic principle of any legal system is not the independence of the individual actor, but its limitation for the community’s sake.’ Footnote 63 The idea of a legal community limiting the sovereignty of states came to be a common theme in the discipline.
3.2. Verdross and natural law
Verdross’ writings stood in this community tradition. Natural law ideas inspired him to believe in legal rules which were superior to formally binding treaties. In Verfassung der Völkerrechtsgemeinschaft (1926), Verdross emphasized that the goal of the transfer of the concept of constitution to the international level was to highlight that ‘international law is not a mere collection of individual fragments which have no inner connection’, but forms ‘a harmonious order of norms’, which is ‘properly called the international legal community’.Footnote 64 Even though Verdross did not (yet) expressively develop a concept of hierarchically higher substantive international legal rules, his belief in international law as a sophisticated legal system was apparent.
Verdross’ community conceptualization of the international legal sphere originated from his philosophical and religious belief in natural law. In the early 1920s he had already referred to ‘international justice’ as a subsidiary source of international law and the foundation of the international constitution.Footnote 65 Also, he stressed that the ‘Christian doctrine of all men as children of God’ represents the ‘ethical-metaphysical foundation’ for the realization of a universal legal order.Footnote 66 In 1937, he emphasized that ‘the classical natural law doctrine’ with its ‘moral foundations’ provides the point of departure for the study of international law.Footnote 67 Verdross explicitly endorsed the tradition of (Catholic) Christian universalism.
Verdross’ ideas about immoral treaties and jus cogens were part of this belief in an international legal community based on natural law. In his writings on void treaties, Verdross stressed that his jus cogens approach was connected to the idea of universally recognized general principles of international law (Art. 38(3) of the Statute of the PCIJ)Footnote 68 which he regarded as stemming from natural law. Further more, he highlighted that the rules on jus cogens had to correspond to the ‘universal ethics of the international community’ and decried a ‘dogmatic positivism which wishes to separate positive law from its ethical mother soil’.Footnote 69 Verdross’ thinking about the jus cogens doctrine was part of the intellectual turn from strict positivist absolute sovereignty to a more relative sovereignty and a deeper value-orientation of international law.
How can this be reconciled with Verdross’ attack on the Paris Peace Treaties? Interestingly, for Verdross, natural law and international justice not only provided the intellectual moral foundation of international law but at the same time enabled him to criticize the ‘unjust’ peace treaties. In his view, the Versailles Treaty rendered it impossible for Germany to defend its people against outside attacks even though Germany, like every other state, was morally obliged to do so. Therefore, the treaty violated jus cogens and was contra bonos mores. The use of this moral reasoning for attacking Versailles demonstrates one potential problem of the jus cogens doctrine: different actors regard different values to be morally imperative and fundamental for the existence of an international community.
3.3. British special rapporteurs and the law of treaties
After the Second World War, the idea of jus cogens caught on. The UN, as the new universal international organization, stood for a more value-laden international law. The UN Charter declared the observance of human rights and fundamental freedoms to belong to the goals of the institution and its members (Arts. 55 and 56). Furthermore, the (non-binding) Universal Declaration on Human Rights became an emblem of the general perception that international law had to be grounded in moral values. As some scholars observed, natural law ideas resurfaced in many different corners of the discipline.Footnote 70 In this context, the idea of higher fundamental norms limiting the free will of states inspired the thinking of many international lawyers.
As Stefan Kadelbach has shown, one important promoter of the jus cogens doctrine was the International Law Commission of the UN. In November 1947, the General Assembly established the Commission in line with Article 13(1a) of the UN Charter and provided it with the mandate to promote the progressive development and codification of international law.Footnote 71 While the first drafts of other expert bodies on the law of treaties had largely been silent on the question of jus cogens,Footnote 72 Hersch Lauterpacht, the Special Rapporteur on the law of treaties, included the topic in his 1953 draft. Article 15 of the first report of the ILC on international treaty law held: ‘A treaty, or any of its provisions, is void if its performance involves an act which is illegal under international law and if it is declared so to be by the International Court of Justice.’ According to the proposal, the illegality of an international treaty did not result from a violation of customary law, but only from a violation of ‘such overriding principles of international law which may be regarded as constituting principles of international public policy (ordre public international)’. These fundamental principles were described as being so ‘expressive of rules of international morality’ that a tribunal would consider them as belonging to the general principles of law (Art. 38(1c) of the Statute of the International Court of Justice (ICJ)).Footnote 73 Apparently Lauterpacht had changed his mind, after Germany had lost the war, the Paris Peace Treaties were no longer an issue and Verdross’ argument about immoral treaties had lost its object. However, it is telling that Article 15 referred to ‘illegality’ rather than ‘immorality’ of a treaty and thus somewhat distanced itself from Verdross’ contra bonos mores idea.Footnote 74
Lauterpacht’s successors at the ILC pursued his path. Sir Gerald Fitzmaurice in his 1958 report explicitly introduced the language of jus cogens: ‘It is essential to the validity of a treaty that it … should not involve an infraction of those principles and rules of international law which are in the nature of jus cogens.’Footnote 75 In his commentary, Fitzmaurice referred to treaties contrary to rules created for the protection of individuals and treaties in which two states conspired to commit an act of aggression as examples for the application of the rule. Fitzmaurice stressed that, as a common characteristic, the rules of jus cogens ‘involve not only legal rules but considerations of morals and of international good order’.Footnote 76
The 1963 draft of the new British Special Rapporteur Humphrey Waldock then laid the ground for the discussion in the Vienna Conference on the Law of Treaties. Article 13 of Waldock’s draft held: ‘A treaty is void if it is contrary to international law and if its object or its execution involves the infringement of a general rule or principle of international law having the character of ius cogens.’ In his commentary Waldock argued that:
[w]hatever imperfections international law may still have, the view that in the last analysis there is no rule from which States cannot at their own free will contract out has become increasingly difficult to sustain. The law of the Charter concerning the prohibition of the use of force in reality presupposes the existence in international law of rules having the character of jus cogens.Footnote 77
The reactions to the proposal demonstrate that the concept had support in many quarters of the (Western-dominated) international legal discipline. In the leading international law magazines in France, the USA, and Germany, Michel Virally, Egon Schwelb and Ulrich Scheuner praised that the draft recognized substantive limits for the action of states.Footnote 78 As the extensive study by Eric Suy on the scholarship on jus cogens demonstrates, various French, Italian, Belgian, Dutch, Spanish, and American authors embraced the normative concept. In the overall academic discussion about four-fifths of the involved international lawyers argued for the existence of so-called indispensable norms (peremptory norms) in international law.Footnote 79 Against the background of the founding of the UN and the crimes of the Second World War, the idea of jus cogens received a lot of support.
4. Embracement by non-Western states
4.1. Controversy at the Vienna Conference
The origins of the jus cogens doctrine cannot only be found in the anti-Peace Treaties strand of German interwar thinking and the value-oriented fight against state sovereignty. Recently, Jean Allain has argued that the decolonization process generated the idea of communal interests in international law. For him, decolonization has been the ‘source’ of jus cogens.Footnote 80 While Allain’s explanation sidelines other historical actors which contributed to the emergence of jus cogens, the endorsement of peremptory norms by non-Western states in the East and in the South played an important role for the universal recognition of the idea at the UN-level.
At the Vienna Conference of Ministers, which was held in 1968 and 1969, the Articles proposed by the ILC were kept with a few changes. Article 53 (formerly Art. 50) of the Vienna Convention was dedicated to ‘treaties conflicting with a peremptory norm of general international law (“jus cogens”)’. The well-known Article holds that:
a treaty is void if, at the time of its conclusion, it conflicts with a peremptory norm of general international law. For the purposes of the present Convention, a peremptory norm of general international law is a norm accepted and recognized by the international community of States as a whole as a norm from which no derogation is permitted and which can be modified only by a subsequent norm of general international law having the same character.
The idea that international law limits the free contractual will of states thereby gained recognition in an instrument with potentially universal outreach.
The discussions at the Vienna Conference between the state representatives on the concept of jus cogens had been controversial. Even though most state representatives acknowledged the need to limit the unbound treaty-making power of states, some also highlighted the dangers of the doctrine. A telling geographical split between opponents and supporters emerged.
Several states from the Western world became sceptical of the jus cogens norms because of their indeterminate character and the risk of misuse. In academia, Georg Schwarzenberger forcefully argued that the jus cogens doctrine could be used as a vehicle for circumventing contractual obligations. The proposal of the ILC ‘leaves everybody free to argue for or against the jus cogens character of any particular rule of international law’. Reminding the actors of the experiences with the clausula rebus sic stantibus, he criticized jus cogens ‘as a means of undermining the sanctity of the pledged word’.Footnote 81 Taking up this criticism, a French delegate at the Conference criticized that jus cogens would drive ‘seeds of insecurity’ into international relations and expressed the fear that the Article might ‘deprive States of one of their essential prerogatives, since to compel them to accept norms established without their consent and against their will infringed their sovereign equality’.Footnote 82 Also, the United States, Great Britain and Belgium (joined by Turkey) declared that, because the identification of jus cogens would hardly be possible, the rules of jus cogens would not be ripe for becoming part of the codification on the law of treaties.Footnote 83 Similarly, the representative of the United Kingdom highlighted ‘what might be jus cogens for one state would not necessarily be jus cogens for another.’Footnote 84 Luxemburg even outright rejected the principle.Footnote 85 In order to limit the notion, Western states in particular (but also states like Lebanon and Turkey) pressed to make the recognition of jus cogens dependent on the decision of the ICJ (Arts. 65, 66(a) VCLT).Footnote 86
When the state parties voted on Article 53 VCLT with 87 in favour, 8 against and 12 abstentions, it was, largely, states from the West resisting the draft. Except for Turkey, the other seven states – Australia, Belgium, France, Lichtenstein, Luxembourg, Monaco, and Switzerland – all came from the West. Furthermore, France became the only state which ultimately voted against the adoption of the whole VCLT because it strongly opposed the codification of the jus cogens concept.Footnote 87 In contrast, most states in the East and the South embraced the idea of jus cogens.
4.2. The Eastern critique of transatlantic and European institutionalization
In the Soviet bloc, the jus cogens doctrine was regarded as a helpful instrument for criticizing the new regional international treaty law created by Western states after the Second World War. In a meeting of the Soviet Society of International Law in 1958, Soviet international lawyers argued for the recognition of various fundamental principles in international law.Footnote 88 With a view to ‘illegal imperialist treaties’, one author stressed that all international law norms which are contrary to fundamental principles cannot be considered as valid.Footnote 89 Another author claimed that peaceful co-existence would be the key fundamental principle of international law. Treaties like the North Atlantic Treaty, the Southeast Asia Collective Defense Treaty and the European Treaties could not be regarded as lawful because they would subvert the UN Charter and international peace.Footnote 90 Furthermore, in the early 1960s, the most famous Soviet international lawyer Grigory Tunkin subscribed to the idea of higher principles in international law which in his reading included Nikita Khrushchev’s foreign policy ideal of peaceful coexistence. The principle of non-aggression for him was the prime example of this idea.Footnote 91 As a member of the ILC, Tunkin was directly involved in the discussions about Waldock’s draft. Even though he preferred to speak of fundamental principles rather than jus cogens, he declared his general agreement with the jus cogens concept. Tunkin argued that as an example for the notion, unequal treaties which establish gross inequalities between the obligations of parties should be mentioned.Footnote 92
Similar views were advanced by East German international lawyers. Rudolf Arzinger embraced the idea that the principle of pacta sunt servanda does not apply if agreements are contrary to fundamental principles of international law. As examples he referred to the prohibition of the use of force, non-intervention, and the right of self-determination. For him, the NATO Treaty and the Treaty of Paris establishing the European Coal and Steal Community were typical examples of treaties which violated these principles.Footnote 93 Hence, for Eastern lawyers, the jus cogens doctrine allowed them to question disliked treaties which stood for the economic and military integration of the West.
4.3. The Global South and the South West Africa cases
Besides the East, non-aligned states also embraced the doctrine of jus cogens. In the discussions of the ILC about the Waldock draft, the Indian and Afghan ILC members Radhabinod Pal and Abdul Hakim Tabibi stressed that the UN Charter, especially its prohibition of aggression and its human rights were examples of such norms.Footnote 94 Furthermore, Pal and the Uruguayan Jiménez de Aréchaga explained the intellectual background of the doctrine. Because the horrors of the Second World War had led to the adoption of the principles of the Nuremberg Military Tribunal and of the UN Charter, international law would now be morally grounded.Footnote 95 Moreover, many Southern governments positioned themselves favourable to the inclusion of the jus cogens draft Articles in the law of treaties. For instance, Algeria, Brazil, Ecuador, Ghana, Guatemala, Indonesia, Iran, Iraq, Morocco, Pakistan, Panama, the Philippines, Syria, Thailand, Uruguay, Venezuela, and the United Arab Emirates belonged to the supporters of the doctrine.Footnote 96
The motivations of lawyers from the Global South to embrace the notions were manifold. As the statements of the ILC members demonstrate, the belief in a value-laden international law as a reaction to the crimes and violence of the Second World War played a role for some lawyers. Moreover, on a more instrumental level, non-aligned states also favoured the principle because it promised to allow them to disengage disliked customary international law norms or treaty obligations. In the 1960s, many decolonized states developed a revolutionary attitude towards some of the existing rules of international law as a product of a system created by imperialist states and demanded that their interests be taken into account.Footnote 97 As the Swiss jurist Paul Guggenheim remarked shortly after the Vienna conference, for him the introduction of jus cogens into the Vienna Convention was a political concession to newly independent states. Like some of his colleagues, he implied that new states might be bound only by jus cogens norms and were free to choose whether they adopted other norms.Footnote 98 With a somewhat different emphasis, the Egyptian George Abi-Saab argued that:
to the extent that jus cogens imposes limitations on the freedom of action of the powerful, wealthy and old established States who muster the greater bargaining power on the international scene, it extends a valuable protection to the newer and weaker States.Footnote 99
That the idea of jus cogens could potentially be used for the benefit of colonized or newly independent states was demonstrated in the South West Africa cases of 1966. During the League of Nations time, South Africa had received the mandate for the former German colony of South West Africa which was supervised under the League of Nations mandate system. After South Africa annexed South West Africa in 1949, the ICJ, in an advisory opinion initiated by the General Assembly, declared that the Union of South Africa could not unilaterally modify the international status of the South West African territory.Footnote 100 However, South Africa did not comply with the opinion. In 1960, the former League members Ethiopia and Liberia then brought a contentious case against South Africa challenging the policies of apartheid installed in South West Africa. At a Conference of Independent African States, South African opposition leaders from the African National Congress had urged the two countries to take the case to the court.Footnote 101 During the ICJ proceedings, the agents based their arguments on the principle of non-discrimination and put forward that ‘South Africa may not claim exemption from a legal norm which has been created by the overwhelming consensus of the international community, a consensus verging on unanimity.’Footnote 102 After the ICJ had decided with a thin nine to eight majority in 1962, that it had jurisdiction to hear the case, four years passed until the decision on the merits. In 1966, by the President’s casting vote, the Court held that the two countries did not have legal standing to bring the claim. Neither Liberia nor Ethiopia would have an individual legal interest in the controversy on behalf of South West Africa because no actio popularis existed in international law.Footnote 103 For the dissenting judges the decision was utterly wrong. They argued that the mandate provided all members of League of Nations with the task to oversee the compliance with the mandate’s obligations and hence all former League members would have a legal interest in the case.Footnote 104
Even though the more expansive reading of the standing issue was not directly connected to the jus cogens idea in Waldock’s draft, the underlying premise of the dissenters was quite clear: since the apartheid system in South West Africa violated the recognized principle of non-discrimination as a fundamental norm of international law, legal standing requirements should not be interpreted too narrowly. Accordingly, the Japanese Judge Tanaka explicitly referred to jus cogens as the basis of his dissenting opinion on the merits of the case. He forcefully emphasized that South Africa had to respect the principle of equality of the South West African people as a human right. To strengthen the claim, he stressed:
If we can introduce in the international field a category of law, namely jus cogens, recently examined by the International Law Commission, a kind of imperative law which constitutes the contrast to jus dispositivum, capable of being changed by way of agreement between States, surely the law concerning the protection of human rights may be considered to belong to the jus cogens.Footnote 105
In the coming years, non-Western states continued to refer to the principle of jus cogens in order to strengthen their legal and political position. As Gennady Danilenko has demonstrated, the new non-Western majority in the General Assembly regarded jus cogens as a legislative tool by which one could transform the traditional notions of international law. At the Third United Nations Conference on the Law of the Sea, many developing countries supported the view that the common heritage of mankind developed in relation to the seabed was a principle of jus cogens. The Chilean representative even proposed explicitly codifying the principle as a peremptory norm in the UNCLOS treaty, a proposal which failed because of the dissent of some Western states like the United States. Moreover, at the Vienna Conference on Succession of States in Respect of State Property, Archives and Debts developing countries claimed that the principle of permanent sovereignty over natural resources which had been highlighted in a number of General Assembly resolutions reflected jus cogens.Footnote 106 Even though the non-Western states were not successful in their attempts to use jus cogens as a tool to change the direction of the Western dominated legal discourse, they put high hopes into the new doctrine and supported its application. Hence, the emergence of jus cogens has also to be credited to the Global South.
5. Conclusion
Since the establishment of the jus cogens provisions in the VCLT, the doctrine of jus cogens has been part of the international legal discourse. Even though the ICJ has been rather reluctant to refer to the notion and has preferred the concept of erga omnes,Footnote 107 in the Armed Activities in the Territory of the Congo case between the Democratic Republic of the Congo and Rwanda, the Court finally explicitly mentioned the doctrine.Footnote 108 Also, other international bodies, like the International Criminal Tribunal for the former Yugoslavia (ICTY), have taken up the jus cogens idea.Footnote 109 Since 2016, the ILC is preparing a report on ‘Peremptory norms of general international law (jus cogens)’, which demonstrates that the notion is at the heart of international law.Footnote 110
This article points to the multifaceted history of the concept. It reminds us that the doctrine originates from different and seemingly contrary lines of thinking. While for German-speaking international legal scholars of the 1920s and 1930s the concept was a tool to revise the Paris Peace Treaties, it was also connected to the fight against absolute state sovereignty and the belief in natural law during the inter-war period. Furthermore, whereas for Soviet thinkers of the Khrushchev era, jus cogens provided a tool to criticize Western economic and military integration and newly independent states regarded the concept as a promising vehicle for distancing themselves from the traditional international legal notions, the embracement of jus cogens as a representation of a more value-laden international law was also a reaction to the crimes of the Second World War. Hence, the relative success of the concept of jus cogens probably also stems from its conceptual openness which allows to apply the notion for different and even contradictory political objectives.
However, despite these underlying tensions, one common theme comes to the fore. The concept appears to be directed against the status quo. After having lost the First World War, Germany intended to reshape the existing international legal system by attacking the Versailles Treaty. During the Cold War, the Soviets, as well as states from the Global South, tried to transform the Western dominated international legal order. At the same time, Western international lawyers put high hopes in the concept as a tool to challenge the free political will of states by providing for a more value-laden international law. In a sense, the losers of the First World War, the Non-Western socialist and decolonized countries and the legal idealist in the ILC all subscribed to a struggle against power.
On a more general level, this article proposes that scholarship on the history of international law should engage with the complexity and multicausality of historical developments. Too many historical accounts by international legal scholars ignore the idea that international legal doctrines and institutions often originate from different lines of thinking. Because legal concepts can be applied in different political and historical circumstances, their development is often influenced by divergent actors and factors. Even though such a mediating historical account does not promise to present the only possible objectively true reading of history, it provides a fuller picture than interpretations which write international legal history via the exclusive perspectives of ‘progress’, ‘non-Western contribution’ or ‘dark sides’ respectively. In a time of ‘alternative facts’, academic scholarship should be careful not to fall in the trap of providing straightforward historical narratives for particular political causes. Instead international legal historians should emphasize the complexity of the manifold usages of legal doctrines by divergent actors over the course of time.
