I. A PARADOXICAL RELATIONSHIP BETWEEN FORM AND AUTHORITY
In an insightful piece published in the American Journal of International Law, David Caron pondered the paradoxical relationship between form and authority that the International Law Commission's Articles on the Responsibility of States for Internationally Wrongful Acts (ASR) convey.Footnote 1 Caron was referring to the curious phenomenon that the ASR should enjoy considerable authority even though, rather than being adopted as a treaty, they were merely ‘taken note of’ by the United Nations General Assembly (UNGA).Footnote 2 Indeed, despite a number of lingering controversies, at the time of their adoption the Articles were already perceived as generally restating the customary international law of international responsibility. Caron's prediction that courts, tribunals and other institutions involved in dispute settlement would be tempted to rely on the ASR without much further probing has proved accurate: in compilations prepared upon the request of the Sixth Committee of the UNGA, the UN Secretary General reported that by 2013 the ASR and the commentaries accompanying them had been cited in 210 decisions.Footnote 3
The Articles on State Responsibility may be one of the most successful codification projects on which the International Law Commission (ILC) has ever embarked on, but they are hardly the only instrument of their kind to present a paradoxical relationship between form and authority. In varying degrees, many of the codification conventions and sets of draft articles that purport to articulate rules of general international law have proved influential, being relied upon by governments, international organizations and judicial and arbitral institutions even when they are not formally binding on the parties to the dispute in question. These instruments are examples of what Nils Jansen has aptly referred to as ‘non-legislative codifications’—texts that the legal profession accepts as authoritative despite the fact that they have not been enacted by the official law-making entities established by the political community.Footnote 4
There are several examples of such texts in legal history. In medieval times, when there was no centralized legislative authority in Europe, the Corpus Juris Civilis was routinely invoked and applied alongside customary law.Footnote 5 Having been ‘rediscovered’ in the eleventh century and adapted to the prevailing social and political conditions by generations of glossators and post-glossators, the Corpus Juris became an invaluable source of legal authority for medieval lawyers.Footnote 6 Even in present times, where developed legal systems are endowed with sophisticated formal procedures for making and applying the law, non-legislative codifications still have a role to play. The most striking example is provided by the Restatements adopted by the American Law Institute, which carry considerable weight before courts in the United States.Footnote 7 Likewise, transnational efforts towards the uniformization of private law, such as the UNIDROIT Principles of International Commercial Contracts, have been a relevant resource in the hands of international arbitrators.Footnote 8
The authority of a particular non-legislative codification depends on the prevailing historical, political and social circumstances of the legal system of which it is part.Footnote 9 What would be the factors explaining the appeal of codification conventions and ILC draft articles in contemporary international law? Traditional commentary regards codification conventions as evidence of State practice and/or opinio juris of the States parties,Footnote 10 and texts produced by the ILC as examples of ‘subsidiary means for the determination of rules of law’ in the sense of Article 38(1)(d) of the Statute of the International Court of Justice.Footnote 11 From a technical perspective, this view is irreproachable: it is widely accepted that treaties may be relevant to prove the existence of international custom, and the work of a Commission composed of individuals elected by the UNGA by virtue of their expertise in international law must surely belong to the ‘teachings of the most highly qualified publicists of the various nations’. But these explanations can be somewhat misleading. Viewing codification conventions and ILC draft articles as individual instances of State practice or the work of law professors does not fully account for the role that these texts play in international legal argument.
What is it that makes these texts so distinctive then? In the present article, I give an account of the factors explaining the authority of non-legislative codifications that have proven influential in international law.Footnote 12 The focus is on draft articles completed by the ILC in an exercise of codification and progressive development of international law pursuant to Article 13 of the UN Charter, and on codification conventionsFootnote 13 concluded by diplomatic conferences on the basis of such draft articles. While the ILC is by no means the only institution to have drafted pivotal instruments of public international law,Footnote 14 it still occupies a unique position and provides a helpful starting point for an analysis that can be later extended to texts elaborated by other institutions.
The article begins by considering how codifications of the non-legislative kind have become current in international law and seeks to substantiate its empirical premise—namely that formally non-binding texts have been taken to reflect international custom (Part II). I argue that, against the background of the endemic uncertainty existing at the level of the sources of international law, institutional features of the ILC, combined with certain properties of the texts that it produces, converge to convey the image that the resulting texts constitute the most authoritative statement of the content of customary international law (Part III). The article then assesses the authority of non-legislative codifications in light of the political ideal of the international rule of law. I suggest that whilst this authority is buttressed by the epistemological difficulties involved in the identification of rules of customary international law, the same epistemological difficulties present a constant challenge to it. This creates a dilemma for members of the legal profession committed to rule of law values—while non-legislative codifications contribute to enhancing the clarity, consistency and congruence of international law, the fact that they may portray novel rules as reflecting existing law raises legality concerns (Part IV).
Before proceeding further, a terminological clarification has to be made. ‘Authority’ ranks amongst the most contested concepts in legal and political philosophy,Footnote 15 and it is necessary to explain how the term is being used here. The focus of the present study is not on the abstract notion of the authority of international law as a set of rules providing reasons for actions and ‘exclusionary reasons for disregarding reasons for non-conformity’.Footnote 16 Rather, authority is here understood as the claim that certain normative texts expressly or implicitly make to reflect existing law (lex lata), and the manner in which this claim is received and endorsed by the legal profession.
II. THE EMERGENCE OF NON-LEGISLATIVE CODIFICATIONS IN INTERNATIONAL LAW
A. A Paradigm Shift: From ‘Legislative’ to ‘Non-Legislative’ Codifications
Since its inception in 1949, the ILC has produced a considerable number of draft articles, guidelines and studies. Examples of successful projects carried out by the Commission are the sets of draft articles that served as a basis for the four law of the sea conventions concluded in Geneva in 1958; the two sets of draft articles that were adopted as the 1961 and 1963 Vienna Conventions on Diplomatic and Consular Relations; the draft articles that served as a basis for the 1969 Vienna Convention on the Law of Treaties (VCLT); and the Articles on State Responsibility, of which the UNGA took note in 2001. The Commission also made contributions to the codification and progressive development of several other fields of international law, including international criminal law,Footnote 17 jurisdictional immunities of StatesFootnote 18 and diplomatic protection.Footnote 19
As an institution, the ILC has been the subject of considerable criticism. Commentators point to problems with the Commission's composition and election, its method of work, and its often unsatisfactory relationship with the Sixth Committee of the UNGA.Footnote 20 Whether the Commission has achieved enough in its 60 years of activity may be a matter of personal opinion, and commentators seem to agree that ‘yes, the Commission has done much’ and ‘no, the Commission could have done more’. Yet, however many criticisms the Commission may deserve, and however many challenges it may face, if it wishes to remain relevant now that several of the main topics of its original programme of work have been finalized,Footnote 21 it is undeniable that the Commission has played a crucial role in shaping the landscape of general international law.
On occasion, the impact of the work of the Commission is demonstrated by the numbers: the 1961 and 1963 Conventions on diplomatic and consular relations have attracted 187 and 173 ratifications, respectively. But this is rarely the case. In its early stages, the ambition of the so-called ‘codification movement’ was to produce conventions that would be eventually ratified by all States thus replacing customary international law with binding codes.Footnote 22 Accordingly, in the first three decades following the establishment of the ILC, members of the Commission and States expressed a marked preference for convening diplomatic conferences to consider and adopt sets of draft articles in treaty form.Footnote 23 This way of proceeding is envisaged by Article 23 of the ILC Statute, pursuant to which the Commission may propose to the UNGA that the Assembly recommend the completed articles to Member States with a view to the conclusion of a convention, or that it itself convene a conference to conclude such a convention.Footnote 24 The prevailing zeitgeist is illustrated by an anecdote concerning Sir Gerald Fitzmaurice and Sir Humphrey Waldock, who both served as Special Rapporteurs for the Commission's work on the law of treaties. Fitzmaurice had proposed that the outcome of the work of the ILC take the form of a non-binding ‘code’, for he did not think that a treaty was the appropriate instrument to enact the general law applicable to treaties.Footnote 25 In contrast, Waldock only agreed to take on the role of Special Rapporteur (and lead the project to completion) on the condition that the Commission redirect its efforts towards the elaboration of a convention.Footnote 26 The reasons that the Commission offered for taking the route proposed by Waldock were that ‘an expository code, however well formulated, [could not] in the nature of things be so effective as a convention for consolidating the law’ and that ‘the codification of the law of treaties through a multilateral convention would give all the new States the opportunity to participate directly in the formulation of the law if they so wished’.Footnote 27
However, the limits of the treaty as an instrument of international legislation were apparent from an early stage.Footnote 28 Even the most celebrated codification conventions failed to command universal adherence. The Vienna Convention on the Law of Treaties, often seen as the highest achievement of the ‘codification movement’, took over a decade to come into force and has been ratified by less than two-thirds of the members of the international community.Footnote 29 At the end of the day, codification conventions concluded with a view to restating general international law have not produced the effect of becoming ‘legislative codifications’ formally binding on States.
As the optimism with respect to the adoption of codification conventions began to wane, the notion that the outcome of the work of the ILC should instead take the form of non-binding restatements experienced a revival.Footnote 30 This opinion had been voiced by a number of early commentators, who thought that codification by treaty should not be attempted due to the inherent shortcomings of treaties as a source of general international law and their potentially detrimental impact on customary law.Footnote 31 Nowadays, ILC members appear to be conscious of the risks involved in the adoption of unsuccessful conventions, and States no longer appear to be interested in convening conferences to discuss matters of general international law.Footnote 32 This means that the other options envisaged by Article 23 of the ILC Statute—most notably that of recommending that the General Assembly ‘take note of or adopt the report [of the Commission] by resolution’—have come to be favoured in the recent practice of the ILC.
The turning point was the adoption of the Articles on Nationality of Natural Persons in Relation to the Succession of States in 1999. Instead of following the recommendation of the Commission, which wished to see the draft articles adopted in the form of a declaration, the General Assembly decided to take note of the articles and annex them to a resolution.Footnote 33 The same course of action was taken when the ASR were submitted to the General Assembly, this time as urged by the Commission itself. At the time when the ILC was about to complete the second reading of the Articles, there was a lively debate on the form that they should take.Footnote 34 Those opposing that the Articles be adopted in the form of a convention claimed that doing so might be a risky enterprise, for a diplomatic conference would reopen debate on polemic issues (such as crimes of State and countermeasures) and upset the balance of a text that had been carefully crafted over four decades.Footnote 35 It was also feared that an unsuccessful convention on State responsibility would result in ‘reverse codification’, as the status of customary rules restated by the draft articles would be put into question if States showed reluctance to ratify that convention.Footnote 36 Thus, on the suggestion of Special Rapporteur James Crawford,Footnote 37 the Commission recommended to the General Assembly that it take note of the Articles, which the Assembly did in Resolution 56/83 of 12 December 2001.Footnote 38 Although the Sixth Committee continues to periodically discuss the ASR,Footnote 39 there is no indication that a conference of plenipotentiaries will be convoked to adopt them in the form of a convention in the foreseeable future.
More recent projects completed by the ILC have also been kept in ‘soft form’. While the Commission did not follow the precedent set by the ASR and recommended instead that the 2006 Draft Articles on Diplomatic Protection be adopted as a treaty, its proposal was met with hesitation by the General Assembly, which does not seem likely to sponsor a conference on diplomatic protection in the near future.Footnote 40 Meanwhile, the Commission has been working on a number of projects that were conceived from the very beginning as ‘soft’ instruments, such as the recently adopted Guide to Practice on Reservations to Treaties.Footnote 41
A notable exception to the current trend was the adoption, via resolution of the General Assembly,Footnote 42 of a Convention on Jurisdictional Immunities of States and Their Property in 2004. This was done on the basis of a set of articles completed by the Commission in 1991 and subsequently revised by a working group of the UNGA. The adoption of the 2004 Convention indicates that, whenever it is necessary or otherwise convenient that rules of international law be enacted in the domestic law of States, treaties will remain the preferred method of codification.Footnote 43 Yet, the Convention on Jurisdictional Immunities is a long way from becoming a ‘legislative’ codification—at the time of writing it had attracted only sixteen ratifications.Footnote 44
B. The Continuing Appeal of Non-Legislative Codifications
This was how the legacy of the ‘codification movement’ in international law has come to consist, for the most part, in codifications of the non-legislative kind, that is, texts that have not taken the form of universally applicable binding codes. But the fact that the codification conventions adopted in the past fifty years have not become universal, and the fact that more recent projects have been kept in ‘soft form’, does not mean that the ‘codification movement’ has been unsuccessful.
In a survey prepared at the behest of the UN Secretary-General in 1949, Hersch Lauterpacht predicted that ILC drafts submitted to the UNGA would enjoy considerable authority even if they were never adopted by a diplomatic conference.Footnote 45 These predictions have proved accurate—successful codification projects tend to have a stabilizing effect and become recurrent reference texts for States, judicial institutions and practitioners.Footnote 46 Thus, the influence that the VCLT has enjoyed within the legal profession is not reducible to the 113 instruments of ratification that States have deposited when expressing their consent to be bound by it. Even before the Convention entered into force, the International Court of Justice (ICJ) had regarded many of its provisions as restatements of customary international law.Footnote 47 And to this day the ICJ has rarely applied the Vienna Convention as a treaty binding on the parties to a dispute. Even in cases involving States that were party to the VCLT, the Convention's inter-temporal law clause led the Court to rely on its provisions only to the extent that they reflect custom.Footnote 48
Most significantly, more polemic codification conventions drafted by the Commission, such as the 1978 Vienna Convention on Succession of States in Respect of Treaties, have on occasion been regarded as authoritative. An example is provided by the Gabcikovo-Nagymaros case, in which the ICJ declared Article 12 of the 1978 Convention, concerning succession to treaties of a territorial character, to reflect a rule of custom.Footnote 49 The 1978 Convention, alongside with the 1983 Convention on Succession in Respect of Property, Archives and Debts, were also influential in guiding State practice in the aftermath of the dissolution of the former Federal Republic of Yugoslavia in the 1990s.Footnote 50 Many more examples could be given in this context. Recently, in the case concerning Jurisdictional Immunities of the State, the ICJ relied on the text of Articles 6(2), 12 and 19 of the Convention on Jurisdictional Immunities of States and Their Property. Even if the Court was reluctant to declare these provisions to be part of customary law (at least not in their entirety), they clearly constituted the starting point for the Court's reasoning in that judgment.Footnote 51
Likewise, the record indicates that international courts and tribunals have adjusted to the current zeitgeist, as recent judicial and arbitral practice has seen a sharp increase in the number of direct references to ILC draft articles. While in the past the ICJ would only make sparse reference to the work of the ILC, usually in construing or assessing the status of provisions of codification conventions,Footnote 52 from 1997 onwards the Court started to cite ILC draft articles directly. In the Gabcikovo-Nagymaros case, the Court relied on Article 33 (currently Article 25) of the draft articles on State responsibility as adopted on first reading, and went on to state that it reflected a customary rule.Footnote 53 Ever since, the Court has applied a number of provisions of the ASR, most notably in its judgment on the merits of the Bosnia Genocide case.Footnote 54 Similarly, in its judgment on preliminary objections in the Diallo case, the Court relied on the text of Article 1 of the Articles on Diplomatic Protection.Footnote 55
The influence exercised by codification conventions and ILC draft articles is of course not confined to the ambit of the ICJ. The compilations prepared by the UN Secretary General show that the ASR have been applied by a diverse group of judicial or quasi-judicial institutions, including arbitral tribunals, the dispute settlement bodies of the World Trade Organization, international criminal tribunals, regional human rights courts and the International Tribunal for the Law of the Sea.Footnote 56 Moreover, the 2011 Articles on the Responsibility of International Organizations were referred by the European Court of Human Rights and by domestic courts even before the ILC had adopted them on first reading.Footnote 57
It must be noted, however, that institutions such as the ICJ sometimes refrain from referring to ILC draft articles in their judgments, even when it is apparent that these articles informed the reasoning substantiating the decision. For example, in the Wall advisory opinion, the Court found that States were under an obligation not to recognize violations of erga omnes obligations committed by Israel, and not to render aid or assistance to maintain the situation caused by these violations.Footnote 58 While this finding echoes the text of Article 41 ASR, which lays down the legal consequences of a serious breach of a peremptory norm of international law, the Court made no mention of that provision.Footnote 59 Likewise, in Belgium v Senegal, where the Court for the first time recognized the notion that multilateral treaties may create obligations ‘erga omnes partes’ in the compliance of which all parties to the treaty have a legal interest, the judgment did not include a reference to Article 48 ASR.Footnote 60 While the Court's reluctance to expressly refer to ILC draft articles in these occasions casts doubt on the extent of their authority, the fact that the Court used language taken directly from the text and commentaries to the articles in question suggests that they provided the normative framework upon which the reasoning of the Court was based. With respect to Article 41 ASR, it is noteworthy that the Court has recently observed that ‘recognizing the immunity of a foreign State in accordance with customary international law does not amount to recognizing as lawful a situation created by the breach of a jus cogens rule, or rendering aid and assistance in maintaining that situation, and so cannot contravene the principle in Article 41’.Footnote 61 This may have fallen short of an explicit recognition of the customary status of Article 41, but it suggests that the Court might have been ready to treat Italy's argument as one grounded in law.
III. INSTITUTIONAL, TEXTUAL AND CONTEXTUAL FACTORS OF THE AUTHORITY OF CODIFICATION CONVENTIONS AND ILC DRAFT ARTICLES
A. The Context of Authority: Uncertainty in Customary International Law
As the survey above indicates, codification conventions and ILC draft articles have been invoked as the textual basis for rules of customary international law that courts and tribunals have found to exist. As in most of those cases courts and tribunals have refrained from undertaking a meaningful examination of the relevant State practice and opinio juris, these non-legislative codifications appear to have been regarded as genuinely authoritative, and not as just another instrument providing evidence of the existence of the relevant rules.Footnote 62 In the Hostages case, the ICJ expressed the view that codification conventions may restate customary international law in the following terms:
The [1961 and 1963] Vienna Conventions, which codify the law of diplomatic and consular relations, state principles and rules essential for the maintenance of peaceful relations between States and accepted throughout the world by nations of all creeds, cultures and political complexions.Footnote 63
In a similar vein, referring to the ASR, an arbitral tribunal constituted to hear the case of Archer Daniels Midland Company and Tate & Lyle Ingredients Americas, Inc v Mexico made the following observation:
The Tribunal acknowledges the fact that the ILC Articles are the product of over five decades of ILC work. They represent in part the ‘progressive development’ of international law—pursuant to its UN mandate—and represent to a large extent a restatement of customary international law regarding secondary principles of state responsibility.Footnote 64
Appraising the relationship between codification conventions or ILC draft articles and customary international law is crucial to understanding the authority of non-legislative codifications in international law. First of all, customary international law provides non-legislative codifications with the formal validation necessary for them to be considered—and invoked as—texts reflecting positive law. However diverse the philosophical inclinations espoused by members of the legal profession may be, it is undeniable that international legal practice subscribes to one or another variation of the sources theory. This means that in international legal discourse valid rules of international law can only be identified by reference to one of the ‘formal sources’, that is, the accepted rules of recognition of the international legal system.Footnote 65
Secondly, it is the inherent uncertainty by which customary international law is characterized that accounts for the influence that non-legislative codifications exercise on members of the legal profession. Non-legislative codifications tend to become authoritative when there is a perceived insufficiency in the law originating from the institutional law-making processes established by the political community. For example, one of the reasons why the Corpus Juris Civilis was applied as law in medieval times was that ‘there were simply no satisfactory alternatives to the Roman texts’.Footnote 66 Likewise, the American Law Institute's initiative to take on the task of elaborating Restatements was animated by the perception that the intricate and fragmented law of the United States was ‘unnecessarily uncertain and complex, that many of its rules [did] not work in practice, and that its administration often [resulted] not in justice, but in injustice’.Footnote 67
In what, exactly, lies the perceived insufficiency of international law? Identifying rules of international custom is an incredibly difficult exercise, especially if one attempts to make sense of the multiple claims, counterclaims, actions and omissions of the 193 States that compose the international community. To quote a leading case, international customary law arises from ‘extensive and virtually uniform’ State practice that is ‘carried out in such a way, as to be evidence of a belief that this practice is rendered obligatory by the existence of a rule of law requiring it’.Footnote 68 This apparently straightforward formula poses a great number of questions.Footnote 69 What counts as State practice? How does one demonstrate the existence of opinio juris sive necessitates? How much practice and opinio juris is required before one can postulate the existence of a customary rule?
These questions are all the more difficult to tackle in a system where there is no centralized system of courts empowered to interpret and apply the law, thus reducing uncertainty.Footnote 70 It is no wonder that the ICJ itself rarely engages in extensive reviews of State practice and opinio juris when it identifies a rule of international custom,Footnote 71 and that the ILC has recently added the topic ‘Formation and Evidence of Customary International Law’ to its programme of work, in the hope of producing a helpful study of the methodology for the identification of customary rules.Footnote 72
It is against this backdrop of uncertainty that the appeal of non-legislative codifications has to be understood. As Caron noted with regard to the ASR, ‘when there is a “legal vacuum” of authority relevant on an issue, courts and arbitral panels will turn to whatever is available’, which means that ‘[i]n that situation, a set of articles adopted by the ILC will be quite influential, perhaps even more influential than a treaty’.Footnote 73 In a similar vein, referring to codification conventions, Baxter noted that ‘the fact that [a codification convention] represents, relative to the rest of the evidence of the law, a clear and uniform statement of the law commends it to non-parties’, especially because ‘[i]t is evidence that is easy to use’.Footnote 74 The epistemological challenges involved in the proof of custom, combined with the reluctance on the part of States to adopt codifying texts formally, set the context for international judges, practitioners, academics and State officials to look to codification conventions and completed set of draft articles as a shortcut for the content of customary international law.
B. The Institutional and Textual Factors of the Authority of Non-Legislative Codifications
A perceived insufficiency in the law is of course not sufficient to explain why non-legislative codifications prepared by the ILC have become so authoritative. What are, then, the other factors inducing the relevant stakeholders to associate codification conventions and draft articles with customary international law? In a recent study on the authority of non-legislative codifications from a comparative perspective, Nils Jansen provides a historical account of classical and contemporary texts that have played or continue to play an important role in their respective contexts.Footnote 75 Whilst noting that the relative authority that each of these texts enjoys depends on prevailing historical, political and social circumstances,Footnote 76 Jansen identifies a number of criteria that help explain why non-legislative codifications are or were regarded as authoritative. These include, on the one hand, authorship of the text, the extent to which the codifying agency is representative of the legal profession (and of the political community in general), and the process whereby the text is drafted; and, on the other hand, formal and substantive properties of the text, and the way each codification ‘stages authority’. As there is a clear parallel between the texts Jansen examines and non-legislative codifications in international law, the present inquiry draws upon his analytical framework.
1. Authorship and representation
The authority of a non-legislative codification partly derives from the position that the entity that produced it occupies in a given legal system. Perceptions relating to the status of the entity, its composition and the procedure it follows in discharging its mandate provide a partial explanation of why the participants in the legal system come to regard the work of this entity as authoritative.
In this respect, the position of the ILC in the ambit of public international law is unique. The Commission was established by the UN General Assembly to fulfil the task of ‘[initiating] studies and [making] recommendations for the purpose of … encouraging the progressive development of international law and its codification’ that States entrusted to the organization.Footnote 77 The ILC Statute requires that a balance be achieved between representativeness and legal expertise in the composition of the Commission: the 34 members of the ILC must be ‘persons of recognized competence in international law’ representing the several regional groups informally identified within the United Nations.Footnote 78 Subject to these criteria, candidates are elected by the General Assembly to exercise a term of five years in the Commission, where they act in their personal capacity and not as representatives of the States that proposed their candidature.Footnote 79 Nowadays, roughly one-third of the members of the Commission are law professors, while the remaining members are former or current governmental officials, mostly diplomats.Footnote 80 Though there is a long-standing debate on what would constitute the ideal composition of the Commission, and despite charges of ‘politicization’, most commentators agree that a balance between academics and governmental officials is beneficial. It is often said that whereas academics ensure that the work of the Commission is technically and methodologically rigorous, governmental officials contribute with their professional experience and ensure that the Commission's output is in tune with the realities of the international life.Footnote 81
In the case of codification conventions, considerations of authorship and representation take on a different dimension. The resulting text is not only the outcome of the work of a codifying agency, but also of the States that debated, amended and eventually voted in favour of it. Codification conventions are usually adopted by international conferences convened under the auspices of the United Nations, which ensures wide representation.Footnote 82 Thus, when a text is adopted by a substantive majority of the States participating in the conference, it is likely to be regarded as an instrument stemming from the international community. As a commentator has pointed out, ‘[c]onventions in the legal field … have tended to influence state practice from the moment of their adoption’, for they ‘represent the verdict by the international community on a set of issues’.Footnote 83 In this case, the subsequent attitude of States—in particular their decision whether or not to sign and/or ratify the treaty—is relevant for assessing the measure of authorship and representation.
At the same time, the fact that States are ultimately responsible for adopting the text does not mean that the role the ILC played in the drafting is to be neglected. The work of the Commission is considered an integral part of the travaux préparatoires of the convention,Footnote 84 and is likely to carry particular weight when the normative status of a provision that was adopted by the diplomatic conference without significant changes comes into question. In North Sea Continental Shelf, the ICJ concluded that because the text of Article 6 of the 1958 Geneva Convention on the Continental Shelf had been adopted ‘almost unchanged from the draft of the International Law Commission’, ‘the status of the rule in the Convention therefore [depended] mainly on the processes that led the Commission to propose it’.Footnote 85
2. Procedure for adoption
The association between codification conventions and ILC draft articles and customary international law is linked both to the procedure whereby the texts are formulated and to certain textual properties of the instruments adopted by the Commission.
I shall begin by discussing procedure. Sets of articles prepared by the ILC are gestated over years of studies and debates.Footnote 86 The Commission appoints a Special Rapporteur that performs the task of guiding the collective work on a given subject by preparing reports, which compile the relevant authorities and (typically) propose a set of draft articles. The Commission discusses these draft articles in plenary and, when general consensus is achieved, sends them to the drafting committee, where the articles are subject to further scrutiny and debate. The work on a given subject usually takes place in two readings, which allows for careful consideration of the feedback given by States and other interested entities. Ultimately, the length of this process guarantees that consideration is given to most of the available materials (State practice, judicial decisions, arbitral awards, scholarly work), which are then cited in the commentaries accompanying the draft articles adopted.
Specific to the procedure followed by the ILC is the dialogue that the Commission maintains with States and other relevant stakeholders. The ILC works in close (if somewhat erraticFootnote 87) collaboration with the Sixth Committee of the General Assembly in a number of ways.Footnote 88 First, the Commission reports to the UNGA on an annual basis. This means that the political organs of the United Nations are informed of the progress and challenges faced by the Commission, and are able to provide it with feedback. Second, the Commission solicits comments from States and, when appropriate, international organizations and other entities, and tends to take their position into account. Third, as noted above, upon completion of a topic the Commission recommends a course of action to be taken by the General Assembly, which normally secures that a set of draft articles will at a minimum be ‘taken note of’ by the Assembly.
Accordingly, when the Commission is most successful, the provisions it formulates reflect a synthesis of scholarly opinion tempered by the general trends emerging from the opinions voiced by States. Even if there is much room for improvement in what concerns the relationship of the Commission with the Sixth Committee, the system of consultations and the exposure that States are given to the work in progress are key factors for the acceptability of a completed project. This contributes to the assumption in the legal profession that a set of draft articles formulated by the Commission may authoritatively restate customary law, or, where disagreement persists, that the solution found by the Commission reflects a plausible compromise.
In the case of codification conventions, this procedure is taken one step further. When draft articles produced by the ILC are formally adopted in a diplomatic conference, States have the last word on their content and drafting. If a provision is adopted by consensus, the general agreement between States as to the text and content of that provision may be an important factor in the assessment of its legal status. As the ICJ noted in North Sea Continental Shelf, a treaty provision can be relevant vis-à-vis non-parties if it codifies a pre-existing customary rule or if it crystallizes an emerging customary rule.Footnote 89 The process whereby a codification convention was concluded may either serve as evidence that its provisions are declaratory of international law,Footnote 90 or that its ultimate adoption effected the ‘crystallization’ of the rule in question.Footnote 91
3. Staging authority: Textual qualities and prescriptive form
The place that the ILC occupies in the UN system, its composition and the procedure that it follows contribute to perceptions that, from an institutional point of view, the Commission is particularly well positioned to restate rules of customary international law. This perception can be reinforced when the text is well received by States in a successful diplomatic conference. But the influence of a non-legislative codification also depends on its textual qualities and the way in which it stages authority.Footnote 92 The codification will only be taken as a reference by the legal profession if it addresses the relevant subject-matter in a clearer and more conclusive way than other available materials. That being so, the form that the text takes is of particular importance in the assessment of its authority.
On the one hand, technical excellence—resulting in a coherent and systematic presentation of the relevant rules—is essential in securing the acceptance of the non-legislative codification. Of course, the standards against which technical excellence are measured change over time. Few would consider that the Corpus Juris Civilis, with its chaotic juxtaposition of legal texts and lengthy doctrinal discussions, would meet current standards of presentation and coherence,Footnote 93 so much that it is somewhat difficult for the contemporary observer to appreciate fully how the Corpus Juris appealed to the medieval lawyer. In contrast, contemporary examples of non-legislative codifications such as the American Restatements and the UNIDROIT principles take the form of systematic sets of prescriptive statements that share many of the characteristics of modern legislative codes and statutes enacted in domestic legal systems. In formulating its draft articles, the ILC draws on the experience of modern legislation, and the technical quality of its texts undoubtedly meets contemporary expectations. As a former member of the Commission pointed out:
The slow, tiresomely slow at times, and repetitive procedures followed by the ILC ensure that its drafts are thoroughly researched and carefully worded. … The ILC is well aware of the fact that if its work is to enjoy authority it will only do so by reason of its quality. This quality is achieved by the excellence of the report submitted by the special rapporteur, the high standard of scrutiny to which the report is subjected in plenary debate, and the meticulously careful attention to the nuances of language displayed by the drafting committee.Footnote 94
On the other hand, the way in which the instrument stages authority, by presenting a clear prescriptive position as to what the law requires, plays an instrumental role in the process whereby a non-legislative codification becomes authoritative. Codification conventions and ILC draft articles invariably consist in a series of provisions drafted in prescriptive form that provide conclusive solutions to legal questions arising from the field that they purport to codify and progressively develop. These texts tend to be relatively accessible and readily applicable to the factual situations that they seek to regulate.Footnote 95 By taking such prescriptive form, they conceal disagreement that may have existed in the practice, precedents and scholarly opinion that substantiated the proposed rules. Likewise, the practice of adopting provisions by consensus, which sometimes can only be achieved through lengthy debate, contributes to understating controversy that may have arisen within the Commission.Footnote 96
To an extent, concealing disagreement is inherent to the process of codification, which, by definition, involves an element of law creation.Footnote 97 Indeed, the process of translating regularly observed practices into words must necessarily involve choices on the part of whoever is entrusted with the task. This is particularly true in the case of international law—as noted above, being a legal system based on customary law which does not comprise judicial institutions with compulsory jurisdiction, international law suffers from endemic uncertainty. The upshot is that, as Hersch Lauterpacht pointed out with respect to efforts to codify the law of treaties and the law of the sea, while there may have been wide agreement as to broad principles of customary law, this agreement collapsed once particular rules and problems were brought to the table. In the case of the law of treaties, Lauterpacht noted that ‘[a]part from that general unavoidable acceptance of the basic principle, pacta sunt servanda, there [was] little agreement and there [was] much discord at almost every point’.Footnote 98 In a way, the codification and progressive development of international law boils down to managing disagreement and proposing sensible solutions that better reflect existing practice, precedent and doctrinal opinion, and that better meet the needs of the international community.Footnote 99
But how exactly does the ILC deal with the uncertainty inherent in customary international law when it undertakes to codify and progressively develop international law? In Article 15 of the ILC Statute, the activities of codification and progressive development of international law are distinguished for reasons of ‘convenience’.Footnote 100 While codification is defined as the ‘more precise formulation and systematization of rules of international law in fields where there already has been extensive State practice, precedent and doctrine’, progressive development is understood as the ‘preparation of draft conventions on subjects which have not yet been regulated by international law or in regard to which the law has not yet been sufficiently developed in the practice of States’. Commentators often point out that any strict differentiation between the two activities is bound to be artificial,Footnote 101 and the Commission took note of this fact at an early stage of its existence. With respect to the codification of the law of the sea, it observed that:
In preparing its rules on the law of the sea, the Commission has become convinced that, in this domain at any rate, the distinction established in the Statute between these two activities can hardly be maintained. Not only may there be wide differences of opinion as to whether a subject is already ‘sufficiently developed in practice,’ but also several of the provisions adopted by the Commission, based on a ‘recognised principle of international law,’ have been framed in such a way as to place them in the ‘progressive development’ category. Although it tried at first to specify which articles fell into one and which into the other category, the Commission has had to abandon the attempt, as several do not wholly belong to either.Footnote 102
A similar approach was taken during the early stages of the codification of State responsibility:
the topic of international responsibility was one of those where the progressive development of international law could be particularly important … . The Commission wishes expressly to state, however, that in its own view the relative importance of progressive development and of the codification of accepted principles cannot be settled according to any pre-established plan. It must emerge in practical form from the pragmatic solutions adopted to the various problems.Footnote 103
While the justification that the Commission provided for taking this approach is persuasive, it is not without consequences, especially when the outcome of the work takes the form of non-binding instruments as opposed to codification conventions. The absence of a distinction between codification and progressive development in the ILC enhances the work of the Commission's potential to stage authority.Footnote 104 Even if it is true that the distinction between the two endeavours cannot be strictly maintained in practice, the vocabulary of ‘codification’ and ‘progressive development’ still holds explanatory power when used to assess the legal status of a project as a whole or of a specific provision. If the project or the provision are said to fall predominantly on the codification side of the spectrum, the elements of progressive development that they may contain are likely to be regarded as negligible, a mere side effect of the codification activity. The project or provision is likely to be applied as reflecting existing law and over time it will be impossible to distinguish what has been restated from what has been created by the codifying agency. Conversely, if a set of draft articles or a specific provision are considered to fall predominantly on the progressive development side of the spectrum, it is assumed that the project cannot exercise any authority of its own unless it is adopted in treaty form, in which case it will be binding solely upon States that have ratified/acceded to the respective treaty.Footnote 105 It is no wonder that some commentators would wish the Commission to be ‘more open and more honest’ in indicating whether it is engaging in codification or in progressive development.Footnote 106
In fairness to the ILC, it does on occasion indicate that certain provisions were proposed in an exercise in progressive development of the law. The distinction can be found in some provisions of the ASR and of the Articles on Diplomatic Protection.Footnote 107 Remarkably, in the general commentary to the 2011 Articles on the Responsibility of International Organizations the Commission stated that ‘[t]he fact that several of the present draft articles are based on limited practice moves the border between codification and progressive development in the direction of the latter’, and that the provisions of that set of articles ‘do not necessarily yet have the same authority as the corresponding provisions on State responsibility’.Footnote 108 But while this caveat calls into question the normative status of the project as a whole, the commentary does not provide guidance on where to draw the line. Individual provisions contained in the 2011 Articles may thus still manage to stage, to a considerable degree, the ‘authority of codification’.
There is yet another way in which the authority of ILC texts appears to have been conveyed in recent times. Now that the adoption of codification conventions has fallen into disfavour, there have been subtle shifts in the way ILC draft articles have been referred to by the General Assembly once the drafting process is completed. In cases where ILC draft articles have been ‘taken note of’ by the UNGA, the word ‘draft’ has been dropped somewhere in the process. Thus, in 2001, after welcoming the adoption of the ‘draft articles’, the UNGA took note of the ‘articles’ on the responsibility of States for internationally wrongful acts.Footnote 109 Subsequently, the Assembly commended the ‘articles on diplomatic protection’ and took of the ‘articles on the responsibility of international organizations’.Footnote 110 International courts and tribunals have tended to follow suit by referring to ILC projects as ‘articles’ instead of ‘draft articles’.Footnote 111 The omission of the term ‘draft’ is of symbolic value and reinforces perceptions that the codification is a finalized project, thereby enhancing its claim to authority.
In short, the use of straightforward prescriptive language which conceals disagreements in practice and in doctrine; the lengthy commentaries presenting the authorities for each and every provision; the conspicuous silence as to the legal status of particular provisions; and even the way ILC projects have been referred to by the UNGA all contribute to bestowing upon the texts adopted by the Commission the aura of a restatement of the existing law.
Before moving further, a few words should be said about how codification conventions stage authority. What has been said about ILC draft articles is also relevant for codifications adopted in the form of a treaty, but it should also be noted that States occasionally seek to further enhance the text's claim to reflect customary international law.Footnote 112 A striking example is the 1958 Geneva Convention on the High Seas, in the preamble of which States recognized that ‘the United Nations Conference on the Law of the Sea, held at Geneva from 24 February to 27 April 1958, adopted the following provisions as generally declaratory of established principles of international law’.Footnote 113 In a similar—albeit more restrained—vein, the preamble of the 2004 UN Convention on Jurisdictional Immunities states that ‘the jurisdictional immunities of States and their property are generally accepted as a principle of customary international law’. In contrast, the preambles of other codification conventions make less categorical statements about the normative status of the rules that they embody; more economically, they tend to refer to ‘the codification and the progressive development’ of international law ‘achieved’ by the convention.Footnote 114
C. Reassessing the Significance of Codification Conventions and ILC Draft Articles as Subsidiary Sources
Factors of authorship, representation, procedure and form enhance the authority of non-legislative codifications originating from the work of the ILC, providing a partial explanation of why codification conventions and draft articles have come to be regarded in international legal discourse as ‘reflections of customary international law’. The level of institutionalization of the Commission and its status as a UN organ should be sufficient to explain why the work of the Commission conveys more authority than the work of non-governmental professional associations which similarly engage in codification activities, such as the Institut de droit international and the International Law Association. As much though these institutions may have contributed to elucidating rules of international law, their resolutions and reports are not given the same recognition as those stemming from the Commission.Footnote 115
Similarly, the traditional position that conflates the work of the ILC with the teaching of international law professors has to be reassessed. As influential as the work of publicists of the likes of Lassa Oppenheim, Hersch Lauterpacht, Charles Rousseau and Roberto Ago may be—to quote but a few late scholars whose membership in the group of ‘highly qualified publicists’ few would dare question—their work is not expressly cited by the participants in the legal system as a depiction of existing law in the same way as codification conventions and ILC draft articles are.Footnote 116 It is telling that a recent empirical study of the use of scholarly writings in judgments of the ICJ found that in a total of 59 citations to ‘publicists’ contained in judgments and advisory opinions of the Court (as of 1 May 2012), 45 were to the ILC.Footnote 117 The better comparison, perhaps, would be between non-legislative codifications and decisions of international courts and tribunals, notably the ICJ, in the sense that both are regarded in legal discourse as highly authoritative statements of the existing law.Footnote 118
Thus, in assessing the significance of non-legislative codifications in international law it is important to observe that these codifications occupy a rather special place in the list of ‘subsidiary means for the determination of rules of law’ envisaged by Article 38(1)(d) of the ICJ Statute. Codification conventions and ILC draft articles are not, of course, to be assimilated with custom, and their characterization as subsidiary sources remains technically correct. And yet, the tendency to associate these texts with customary international law makes it somewhat simplistic to treat them as mere evidence of State practice or as the work of publicists. Their unusual authority, which cannot be easily placed within the scheme of the formal sources of international law, is bound to raise normative concerns. The next section focuses on one of the perspectives from which these concerns can be addressed—that of the international rule of law.
IV. NON-LEGISLATIVE CODIFICATIONS AND THE INTERNATIONAL RULE OF LAW
A. Legality Concerns Posed by Non-Legislative Codifications
As noted above, when ILC draft articles and codification conventions are perceived as restatements of existing law, they are likely to exercise authority even when not formally adopted by States. In other words, the authority of the outcome of the Commission's work depends on its being regarded as ‘codification projects’ as opposed to ‘progressive development projects’. Similar considerations apply to codification conventions, the text and travaux préparatoires of which may provide guidance for assessing their customary status.
It has also been stressed that the context in which this authority becomes possible is that of uncertainty in customary international law. However, just as the uncertainty of customary international law accounts for the appeal of non-legislative codifications, it also sets the limits of their authority. Because neither the ILC nor international conferences are given the competence to legislate, the normative status of provisions embodied in codification conventions and draft articles can always be challenged by reference to the same State practice, opinio juris and relevant precedents that inspired the formulation of those provisions.Footnote 119 Ultimately, each and every provision has to stand on its own merits. Considerations of authorship, representation and procedure may establish a presumption in favour of the view endorsed in the non-legislative codification,Footnote 120 but one should not too easily succumb to the temptation of endorsing this view solely on the basis of such considerations. As Caron warned judges and arbitrators in his essay on the ASR:
[t]o apply [the ASR] correctly, decision makers must avoid a simple reading of the articles but, instead, must consult the commentaries and reports for each article, which illuminate the practice underlying the rule, the discussions of the ILC, and the complements of various governments. Together these sources bring life to the articles and reveal the degree of consensus.Footnote 121
That uncertainty in customary law should both set the context for the authority of non-legislative codifications and at the same time make this authority precarious means that members of the legal profession are put in a difficult position. Given that the formidable epistemological challenges surrounding the proof of customary international law can rarely be avoided, how far should the law-applier committed to rule of law values second-guess the compromise solutions reached by the ILC and diplomatic conferences in codifying and progressively developing international law? To put the question in normative terms, how are these non-legislative codifications to be evaluated when one takes the perspective of the political ideal of the international rule of law?
A brief overview of this political ideal is apposite here.Footnote 122 In recent times, the international rule of law has become a prominent feature in international political discourse. That legality is a goal to be promoted in the international sphere is for example affirmed by several resolutions and declarations adopted under the auspices of the United Nations.Footnote 123 It is nevertheless true, as Arthur Watts pointed out, that the rule of law in international affairs has been more frequently invoked than properly understood.Footnote 124 It has been invoked inter alia to convey the necessity of obeying international law, as an argument for expanding the scope of international regimes, and as a tool for criticizing the behaviour of States and international institutions.Footnote 125
Transposing the political ideal of the rule of law from the domestic to the international context is no easy task, especially when one considers the institutional challenges that a legal system not possessing centralized institutions to enact and apply the law faces.Footnote 126 Yet, it is widely accepted that the principles of generality, publicity, non-retroactivity, clarity, absence of contradictions, possibility of performance, constancy over time and congruence that Lon Fuller has famously identified should be adhered to if international law is to constitute a healthy, functional legal system.Footnote 127 The assumption, therefore, is that one can evaluate international law by some of the same standards by which one evaluates domestic law. There is no reason why one should not embrace a robust conception of the international rule of law if the political ideal is to be taken seriously.Footnote 128
Some of the difficulties posed by non-legislative codifications from the perspective of the international rule of law should then become apparent. First, the practice of applying provisions of codification conventions and ILC draft articles that only putatively reflect existing law is not conducive to international legality. The rule of law pedigree of a non-legislative codification is bound to remain problematic.
Second, moving from the legal to the institutional level, rule of law concerns may lead one to question the manner in which institutions such as the ILC engage in governance functions. At a time when influential codification projects have been kept in soft form, with the ILC having the last word on their content and drafting, it could be asked whether the Commission is not exercising ‘public authority’ in the sense that it is putting forth rules that ‘determine’ participants in the legal system by reducing their freedom of action or affecting their legal or factual situation.Footnote 129 In particular, one has to consider what it is appropriate for a codifying agency such as the ILC to do, and the extent to which it is justified in conveying the impression that it is restating existing law when in fact it may be only managing disagreement. At the same time, it is important to bear in mind that States not only have the ultimate control over the process of codification and progressive development of international law: they are also ultimately responsible for it. Any evaluation of the ‘legislative authority’ that the ILC may be inadvertently exercising has to take into consideration the fact that States may consider to be in their interest that the codification process favour formally non-binding draft articles over conventions.Footnote 130
B. Non-Legislative Codifications and the Concretization of the International Rule of Law
Paradoxically, while the authority conveyed by non-legislative codifications raises these legality concerns, it is precisely the notion of the international rule of law that animates the pursuit of the codification and progressive development of international law.Footnote 131 International law, as an evolving legal system rooted in custom, is at pains to meet two requirements that, often taken for granted at the domestic level, are essential for the concretization of the rule of law. The rule of law presupposes that, first, the relevant social behaviour of the subjects of the legal system be governed by law (the requirement of completeness), and, secondly, that legal rules and principles achieve the degree of determinacy that is needed to render them intelligible and operational (the requirement of determinacy).Footnote 132
Does international law meet these requirements? Can it do so? However many challenges the uncertainty of international custom may create, the notion that international law constitutes a legal system that is relatively complete and sufficiently determinate is a regulative idea to which the legal profession adheres.Footnote 133 International law may contain lacunae and areas in which the existing law will be difficult to ascertain, but it provides a number of accepted methods with which these problems can be addressed. On the one hand, ‘closure rules’ such as the so-called ‘Lotus principle’, whereby freedom of action is inferred from the absence of a prohibition, may be of help in certain situations.Footnote 134 On the other hand, the general principles of law to which Article 38(1)(c) of the ICJ Statute makes reference were conceived to make ‘available without limitation the resources of substantive law embodied in the legal experience of civilized mankind’.Footnote 135
But more fundamentally, the notion that international law constitutes a system that can cope with indeterminacy also influences the way statements about customary international law are made. The fact that inquiring into State practice and opinio juris may produce a dubious or inconclusive result is not always taken to mean that there is no law governing a certain matter. Codification conventions and ILC draft articles, insofar as they aspire to provide a sensible synthesis of competing trends in State practice, legal precedent and doctrinal opinion, are relied upon by law-appliers whose starting point is the premise that there may some be customary law to be found. This refines what has been said above about uncertainty as a context for the authority of non-legislative codification in international law. The notion of the international rule of law animates members of the legal profession to persevere in the search of existing rules of customary international law and is part of the explanation of why they feel justified to treat codification conventions and ILC draft articles as authoritative instruments.
In this respect, it is also helpful to consider how non-legislative codification may be part of the process whereby international custom is formed. It is a truism that the emergence of international organizations has had a great impact on the making of international law.Footnote 136 Ever since permanent international forums assisted by secretariats and relying on well-developed rules of procedure became available, the logistics of multilateral treaty-making has been considerably facilitated.Footnote 137 But the emergence of international organizations has not only had an impact on how treaties are concluded: it appears to have also affected the way in which custom emerges.
In a particularly illuminating study, Georges Abi-Saab distinguishes between the ‘traditional custom’ that the international legal system has inherited from its formative period and the ‘new custom’ that is in the process of formation with the help of international institutions.Footnote 138 While traditional rules of customary international law such as those pertaining to diplomatic relations originated from a lengthy process of consolidation of actions and convictions of States, a process which was at the same time spontaneous and heterogeneous, more recent rules of customary international law are the product of relatively centralized and deliberate law-making processes that often occur under the auspices of the UN and other international organizations.Footnote 139 In the formation of this ‘new custom’—of which the law of the outer space, the law of self-determination and new aspects of the law of the sea are examples—the starting point for the creation of new rules has been a somewhat detailed set of provisions that a majority of States endorse by inter alia voting in favour of resolutions of the UNGA or adopting conventions in a diplomatic conferences.Footnote 140 This means that the emerging opinio juris is often expressed before the required general practice takes shape: first States indicate that they are inclined to consider the negotiated rule as required by law, and then State practice starts to converge on what the negotiated rule prescribes.Footnote 141 Thus, the ‘new custom’ subverts the logic behind the formation of traditional customary rules, in which opinio juris was distilled from a general practice followed over a relatively long period of time.Footnote 142
This phenomenon points to the constructive role of non-legislative codifications in international law. Though a codification convention or a set of ILC draft articles will in part reflect ‘old custom’, they will also be the catalysers of ‘new custom’. As Robert Jennings put it, ‘in the procedures which have developed under Article 13(a) of the [UN] Charter, we have to hand and actually working a procedure which is not limited to drafting and proposing but is, within its limits, genuinely law-making’.Footnote 143 In due course, through converging practice and the work of other authoritative institutions in the system, the initial uncertainty associated with the status of specific rules embodied in non-legislative codification may be overcome.Footnote 144 And one of the reasons why practice comes to converge on the new rule may be precisely the putative claim that the provision (explicitly or implicitly) makes to reflect already existing law.
Appraising the role of codification conventions and ILC draft articles from this perspective makes it easier to consider how these texts can contribute, in the longer term, to promoting international rule of law values. If on the one hand concerns may arise when a codification convention or a set of draft articles stretches the barrier between the lex lata and the lex ferenda, such instruments play a pivotal role in building an international legal system that is functional and in which the requirements of clarity, publicity, absence of contradictions and congruence are abided by.
All of this does not—and could not—solve the dilemma in which members of the legal profession relying on non-legislative codifications may find themselves in situations of doubt, as a rule of law approach will still require them to rigorously identify—and reject—unwarranted claims to authority that such codifications may make. What can then be expected from international lawyers? The caution suggested by Caron is definitely part of the answer, but this does not mean that members of the legal profession should be excessively suspicious of non-legislative codifications. Ultimately, an awareness of the context and factors militating in favour of the authority of codification conventions and ILC draft articles, combined with an awareness of the role that these texts may play in the crystallization or formation of new rules, is instrumental for the law-applier called upon to appraise the weight to be given to non-legislative codifications in individual cases.
V. CONCLUDING REMARKS
Non-legislative codifications, here understood as codification conventions that are not applicable qua treaties and draft articles produced by the ILC, have been enjoying considerable authority in international legal argument, being often cited by courts and tribunals as ‘reflections of customary international law’. Regarding them merely as evidence of State practice (in the case of codification conventions) or the teaching of publicists (in the case of ILC draft articles) falls short of properly appraising the pivotal role that these texts have played and continue to play in articulating rules of general international law. This article provided an account of the factors that, in the context of uncertainty that characterizes the international legal system, explain the appeal of non-legislative codifications within the legal profession. These are the position of the ILC within the UN system; a procedure which includes a dialogue with States and other relevant entities; the prescriptive form that the texts take; the tendency not to distinguish between codification and progressive development; and the eventual recognition or adoption of the texts by the UNGA or diplomatic conferences. The article also emphasized the ultimate limits of the claim to authority that non-legislative codifications explicitly or implicitly make, and pondered the dilemma in which the law-applier committed to rule of law values may find herself when called upon to consider a provision originating from any these codifications.
The authority that codification conventions and ILC draft articles have enjoyed in recent times points to some of the structural deficiencies faced by a legal system in which neither treaty law nor international custom satisfactorily ensure the certainty and determinacy to which—at the level of general rules of universal application—the system aspires. At the same time, it points to the ways in which the system has managed to evolve and become more sophisticated in spite of these shortcomings. Thus, if the fact of this authority is in many ways troubling, it is also auspicious. It is hoped that a clearer understanding of the context and factors explaining the appeal of codification conventions and ILC draft articles may shed light on the process whereby contemporary international law is made and lead to a sensible use of these texts by members of the legal profession.
