oking it has complied with the procedural and substantive provision of that other treaty. But, what if, applying Pauwelyn’s treatyconflict rules, a WTO panel reaches the conclusion that the nonWTO treaty should prevail, but that the WTO Member invokingsuch non-WTO treaty has not complied with procedural requirement(s) of that other treaty. Should the WTO adjudicating body rulethat the non-WTO provision prevails and that there is no WTOviolation, despite that Member's non-compliance with the procedural requirement(s) of the other treaty? In our view, Pauwelyn’sapproach creates more problems than solutions.If the WTO applicable law cannot be interpreted so as to avoidconflict of norms with a provision of another treaty, WTO adjudicating bodies would not be able to enforce non-WTO provisions orgive them direct effect in the WTO applicable law, if the outcomewas that the superseding provision added to or diminished or evenamended the rights and obligations in the covered agreements. Setting aside jus cogens, States do have the right to create judicial andremedy systems that would not be able to enforce all internationalobligations of the same States. Consequently, these non-WTOnorms are binding on the same States (also WTO Members), and ifStates violate them, they will be held responsible, but in anotherjurisdiction (and rules on State responsibility may apply). Bothsystems of State responsibility operate in parallel; the WTO simplybeing a specific one. Our approach simply reflects the present stateof international law which is characterized by an imperfect coherence between international legal regimes and jurisdictions exists.
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Elsewhere,43 Pauwelyn has also argued that Members are presumed to have accepted the binding effect and the direct applicationof general international law into the WTO law. According to Pauwelyn, general international law can fill in the gaps of the WTOtreaty and provisions of non-WTO treaties that are binding on theparties can be invoked in defense of alleged WTO violations. If therelevant customary conflict rules demonstrate that a non-WTO rulemust prevail, ‘then the WTO rule cannot be applied (and the defendant wins)’. For Pauwelyn, this would not result in ‘requiring theWTO panel to judicially enforce the other rule of international law’and ‘the panel would not be ‘diminishing’ the rights of the complainants, as the complainant would have agreed to these conflicting rules in the first place’.In addition to being contrary to the wording of the DSU, Pauwelyn’s suggestion would require WTO adjudicating bodies to interpret the other treaty to decide on its compliance or violation bythe concerned WTO Member and to draw legal consequences overand above the provisions of the WTO treaty. As previously stated,the WTO adjudicating bodies are not courts of general jurisdictionand they cannot interpret and apply all treaties involving WTOMembers. The covered agreements are explicitly listed and it cannot be presumed that Members wanted to provide the WTO remedial system to enforce obligations and rights other than those listedin the WTO treaty. If they were to allow a non-WTO provision tosupersede and set aside a WTO provision and therefore, give it legal effect and enforce a non-WTO provision in superseding a WTOprovision, they would be adding or diminishing the WTO coveredagreements (or even amending it). There is no evidence whatsoeverto even suggest that during the Uruguay Round the drafters of theWTO treaty ever wanted to provide non-WTO norms with directeffect into WTO law and allow Members to benefit from free use ofthe WTO remedial mechanism to enforce rights and obligationsother than those of the WTO treaty.In our view, Pauwelyn’s position disregards the fact that noperfect coherence between international legal regimes exists andthere is not yet a perfect organisational coherence of internationaljurisdictions. When faced with imperfect sharing of international responsibilities, Pauwelyn ironically elevates WTO panels and theAppellate Body into a world dictator of sorts. Moreover, Pauwelyn43
Pauwelyn (2001).
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overlooks that a solution to any conflict between WTO rules andother non-WTO rules should also take into account the legal factthat sovereign States decided to agree to trade rules and an enforcement mechanism different from that of other international obligations. Whether this is good or bad, is a question beyond thescope of this paper.Importantly, genuine situations of conflict of norms will occurvery rarely and through good faith interpretation, WTO law andother provisions of international law can generally be applied harmoniously and effectively. Having said that WTO panels and theAppellate Body cannot interpret and enforce non-WTO other thanto the extent necessary to interpret and apply WTO provisions, oneshould not underestimate the coherence that already exists betweenWTO law and the other systems of international law. It is our suggestion that conflict of norms should continue to be construed narrowly. A broad definition of conflict would lead to a result in whicha third party (an adjudication body or a treaty interpreter) is conferred the power to set aside provisions that have been voluntarilynegotiated by States.IV. ConclusionIt is important to emphasize that States must at all times complywith all their international obligations and respect the rights of otherStates.The issue of WTO Members' State responsibility for a violation of an international obligation or their obligation to respectother States’ rights under treaties other than the WTO is not a matter for the WTO dispute settlement. It is important to recall thatWTO Members remain responsible for the consequence of violations of their international obligations. In situations where a nonWTO treaty provision could potentially supersede a WTO provision, but could not be directly applicable into the WTO legal system or enforced by WTO adjudicating bodies, the State invokingthe non-WTO provision would still be able to invoke the application of the general international law rules on State responsibilityagainst other States (also WTO Members) or other relevant systemsof law for the violation of the non-WTO provisions.4444
Paragraph 5 of Article 30 of the Vienna Convention on the Law ofTreaties provides that: ‘Paragraph 4 [lex posterior] is without prejudice to article 41, or to any question of the termination or suspension
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At the moment, in international law, there does not seem to beany complete co-ordination of systems of international law andthere are several treaties on multiple and overlapping matters. Asingle measure may violate a treaty and be consistent with anotherone. It is thus possible to envisage a situation where an internationaltribunal would reach a conclusion that a measure (that is also [partof] a WTO measure) is inconsistent with a (non-WTO) treaty, whilethe WTO adjudicating body may reach the conclusion that the samemeasure is consistent with the WTO treaty. As required under international law, the measure would have to be modified to complywith the non-WTO treaty law while continuing to be compatiblewith WTO law; and most of the time this should be feasible. Theruling of the WTO adjudicating body would only relate to the WTOaspects of the measure and would not affect or deal with the compatibility of the same measure with the non-WTO treaty.Various suggestions have been offered to try and ‘constitutionalize’ international courts and jurisdictions. We still believe thatStates’ multiple international rights and obligations can be interpreted and applied harmoniously and coherently. In this regard, weshare the following perspective, that seems the most astute in thepresent state of international law:‘With the greatest respect to the past two Presidents of theInternational Court, I do not share their view that themodel of Article 234 (the renumbered Article 177) of theRome Treaty provides an answer. It is simply cumbersome and unrealistic to suppose that other tribunals wouldwish to refer points of general international law to the International Court of Justice. Indeed, the very reason fortheir establishment as separate judicial instances militatesagainst a notion of intra-judicial reference.The better way forward, in my view, is for us all to keepourselves well informed. Thus the European Court of Justice will want to keep abreast of the case law of the international Court, particularly when it deals with treaty lawor matters of customary international law; and the International Court will want to make sure it fully understandsof the operation of a treaty under article 60 or to any question of responsibility which may arise for a State from the conclusion or application of a treaty, the provisions of which are incompatible with itsobligations towards another State under another treaty.’
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the circumstances in which these issues arise for its sistercourt in Luxembourg [...].’45In conclusion, despite some criticisms offered on our colleague’s paper, it should be borne in mind that we greatly appreciate yet another of his outstanding contributions to the field of publicinternational law and WTO law as well as the relationship betweenboth. In the final analysis, however, Joost’s assertion that the purpose of his paper is to take the relevance of non-WTO law beforeWTO panels a ‘step further’ is instructive, inasmuch as WTO panels should be reluctant, at present, to take that ‘step further’.
ReferencesJames J. Fawcett (1995), Declining Jurisdiction in Private International Law, Oxford (Oxford University Press) 1995.Gerald Fitzmaurice (1957), The Law and procedure of the International Court of Justice, in: British Year Book of InternationalLaw 34 (1957), 237.Roselyn Higgins (2003), The ICJ, The ECJ, and the Integrity of International Law, International and Comparative Law Quarterly52 (2003) No. 1, 1-20.Wilfred Jenks (1953), The Conflict of Law-Making Treaties, in:British Year Book of International Law 30 (1953), 401-453.Robert Jennings / Arthur Watts (eds.) (1992), Oppenheim’s International Law, London (Longman) 91992.Wolfram Karl (1984), Conflicts Between Treaties, in: Rudolf Bernhardt (ed.), Encyclopedia of Public International Law Vol. 7,Amsterdam / London / New / Tokyo (North Holland) 1984,468-473.Vaughan Lowe (1996), Res Judicata and the Rule of Law in International Arbitration, African Journal of International Law 8(1996), 38-50.Vaughan Lowe (1999), Overlapping jurisdiction in internationaltribunals, in: Australian Year Book of International Law 20(1999), 191-204.45
Higgins (2003), 20.
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Gabrielle Marceau (1997), Dispute Settlement Mechanisms, Regional or Multilateral Agreement: Which One is Better?, in:Journal of World Trade 21 (1997) No. 3, 169-179.Donald M. McRae (1996), The contribution of international tradelaw to the development of international law, in: Recueil descours 260 (1996), 99-238.Donald M. McRae (2003), Claus-Dieter Ehlermann’s Presentationon ‘The Role and Record of the Dispute Settlement Panels andthe Appellate Body of the WTO’, in: Journal of InternationalEconomic Law 6 (2003) No. 3, 709-717.Joost Pauwelyn (2001), The Role of Public International Law in theWTO. How Far Can We Go?, in: American Journal of International Law 95 (2001) No. 3, 535-578.Emmanuel Roucounas (1987), Engagements parallèles et contradictoires, in: Recueil des cours 206 (1987-VI), 9-288.Takao Sawaki (1979-80), Battle of Lawsuits – Lis Pendens in International Relations, in: Japanese Annual International Law 23(1979–80), 17-29.Ian M. Sinclair (1984), The Vienna Convention on the Law ofTreaties, Manchester (Manchester University Press) 21984.E. W. Vierdag (1988), The Time of the ‘Conclusion’ of a Multilateral Treaty: Article 30 of the Vienna Convention on the Law ofTreaties and Related Provisions, in: British Year Book ofInternational Law 59 (1988), 100.
Erich Vranes*
Comments on Joost Pauwelyn’s Paper: ‘How to Win aWTO Dispute Based on Non-WTO Law?’I. Introduction: Areas of DisagreementII. The Definition of Norm ConflictIII. Jurisdiction and Applicable Law in WTO ProceedingsA. The Positions JuxtaposedB. Legal Starting-Points and Central QuestionC. Substantive Law: Restricted Capacity ofPanels and WTO Members?D. WTO Dispute Settlement: An (Absolutely)Exclusive Forum?IV. ConclusionsReferences
838489899293959798
I. Introduction: Areas of DisagreementThe following comments concentrate on the areas of disagreementin the positions of Joost Pauwelyn on the one side and GabrielleMarceau and Anastasios Tomazos on the other. As Joost Pauwelynand Gabrielle Marceau are two of the main proponents in the debate on the relationship between international law and the WTOsystem, in dealing with their views one has to address several of thecore issues raised in this discussion so far. In order to better understand these issues and the respective positions presented, it appearsappropriate to take some of their earlier writings into perspective.Joost Pauwelyn’s position can be summarized quite succinctly.According to him, one has to distinguish jurisdiction and applicablelaw. Against this background, he argues first that a panel’s jurisdiction can be taken away through international agreements that do notform part of WTO law. Similarly, Pauwelyn submits that substantive rules of international law conflicting with WTO law can be*
Europainstitut, Vienna University of Economics and Business Administration.
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invoked as a defence even within WTO proceedings. Both contingencies depend on the principles of international law, in particularArticles 41 and 30 of the Vienna Convention.Underlying Pauwelyn’s approach is a wide definition of conflict. Although not extensively addressed by Pauwelyn in his present paper, Marceau and Tomazos deal with this fundamental issuein more detail. According to Pauwelyn, explicit permissions to restrict trade in other treaties may prevail over WTO law, dependingon the rules of international law. Importantly, it follows that ArticleXX of the GATT and other WTO exceptions, WTO provisionsincorporating non-WTO norms by reference, and waivers are notthe unique or primary links to non-WTO international law: a WTOMember which is required or permitted to restrict trade by a nonWTO treaty need not comply with clauses like Article XX (andneed not employ the least trade-restrictive means e.g. under ArticleXX(b)), if WTO law is superseded by a given non-WTO treaty.On all of these issues, there is disagreement between Pauwelynon the one hand and Marceau and Tomazos on the other. We willaddress these questions in consecutive order, starting with that ofthe appropriate definition of norm conflict, which underlies thewhole topic.II. The Definition of Norm ConflictIn contrast to Pauwelyn, Marceau and Tomazos argue that the notion of conflict of norms should be defined narrowly. In their view,a conflict exists only where ‘a provision of the WTO Agreementmandates an action that a provision of another treaty prohibits orvice versa, when a provision of another treaty mandates an actionthat the WTO Agreement prohibits.’1 This is in line with what arguably constitutes the predominant position in writings on international law.2 While Marceau and Tomazos cite the Appellate Body12
Cf Marceau / Tomazos in this volume at 77 (italics added).Cf Jenks (1953), 426; Marceau (2001), 1081. Several other authors,among them Czaplinski / Danilenko (1990), 12-13; and most recentlyWolfrum / Matz (2003), 4 have also opted for narrow definitions ofconflict; yet it is not always clear whether in doing so they are awareof the particular problem of conflicts between permissive and prescriptive or prohibitive norms. Moreover, the proposed definitionsare often open to different interpretations. Thus Klein (1962), 555,Wilting (1994), 2-12 and Kelsen (1979), 99-100 have been under-
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report on Guatemala – Cement I in their support,3 it must be emphasized that a different position has been taken by the panel in theBananas III case.4It is indispensable briefly to recall some fundamentals of thetheory of norms, in order to be in a position to assess the diametrically opposed positions of Marceau and Tomazos on the one handand Pauwelyn on the other. It has already been pointed out by Bentham in his Of Laws in General that the multitude of legal provisions and complex legal concepts (such as ‘competence’, ‘property’etc) can be reduced to (sets of) ‘complete norms’, that is norms ofconduct, namely prohibition, obligation, positive and negative permission.5 In this regard, deontic logic6 and the imperative theory oflaw are congruent. A norm of conduct consists of two parts, that isto say a deontic operator which expresses the obligation, prohibition, or permission, and a descriptive proposition which can be anyconduct. All of these ‘basic units’ of legal thinking are interdefinable through negations. Thus, if the prohibition of a given conductis negated, this same conduct is permitted, and vice versa. In otherwords, the prohibition of a given conduct constitutes the contradictory opposite of the permission of this conduct (‘non-prohibition’,positive permission). The same is true for the permission to forbearfrom adopting a given conduct and the obligation to adopt this con-
3
4
56
stood as giving strict definitions, excluding any incompatibility ofpermissions and prescriptive norms. In relation to Kelsen, in particular, this interpretation appears problematic, as he adopted a widedefinition in his General Theory of Norms, where he expressly stated‘... that one cannot deny that a permission and a prescription mutually exclude each other’ (Kelsen (1979), 79). A wide definition hasrecently been adopted by Weiss (2003), 201 et seqq., who concurswith the 1997 Bananas panel report (cf in the following).Cf WTO Appellate Body, Guatemala–Anti-Dumping InvestigationRegarding Portland Cement from Mexico, WTO Doc.WT/DS60/AB/R, in particular at paras 65-66 (Nov. 5, 1998).Cf WTO panel report, European Communities-Regime for the Importation, Sale and Distribution of Bananas, WTO Docs.WT/DS27/R/ECU/GUA/HON/MEX/USA, paras 7.158-7.159 and fn792 (September 27, 1997).Cf Bentham (1970), 93-109 and 156-183.On this cf e.g. Weinberger (1989), 228 et seqq.; Lenk (1974), 198 etseqq.; Alexy (1994), 182-194; Adomeit (1986), 26-29 and 82-86.
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duct: negating this obligation yields a permission of contradictorycontent (‘non-command’, negative permission), and vice versa.Prohibition and obligation are also interdefinable, if the conductwhich is regulated (the descriptive proposition) is negated.7 All ofthese constellations – permission vs prohibition, permission vs obligation, prohibition vs obligation etc – are recognized as conflicts inlegal theory. The first two are normally referred to as contradictoryconflicts; the last (prohibition vs obligation) is termed contrary conflict. In short, there is a conflict ‘if a given behaviour appears inabstracto or in concreto as prescribed and not prescribed, or as prohibited and not prohibited, or even as prescribed and prohibited’.8Importantly, legal definitions, exceptions (such as Article XXof the GATT), norms referring to other norms or setting out legalfictions etc are merely parts of the antecedent (the if-clause) ofcomplete norms.9 Thus, a complete norm is equivalent to the complete expression of the legislator’s (or the contracting parties’) willin respect of a given conduct or class of conduct. It therefore varies,in extent and complexity, from a simple command to a multitude oflegal provisions, depending in particular on the degree of a norm’sgenerality,10 and the number of exceptions, definitions etc whichhave to be taken into account as preconditions by the decisionmaker called upon to apply the norm, or the conflicting norms.As indicated, Pauwelyn has submitted that the notion of conflict of norms should be defined widely so as to encompass conflicts between prohibitions and obligations (prescriptive norms) onthe one side and permissions on the other, a position which in factis in line with the understanding in legal theory. Marceau andTomazos in contradistinction only accept those constellations as7
8
910
Let us assume the conduct in question is ‘to stay in Vienna’. A givennorm may prohibit a person from ‘staying in Vienna’. The negationof this conduct is ‘not staying in Vienna’. If this person is prohibitedfrom ‘not staying in Vienna’, the person is actually under an obligation ‘to stay in Vienna’. Thus, negating the descriptive part of a prohibitive norm yields the contrary obligation and vice versa.Engisch (1977), 162 (‘Ein Verhalten [erscheint] in abstracto oder inconcreto zugleich als geboten und nicht geboten oder als verbotenund nicht verboten oder gar als geboten und verboten’).Cf e.g. Hart (1971), 59-66; Hart (1992), 26-48; Thon (1878) 2 etseqq., 325, 338-339 and passim; Röhl (1995) 228.Bentham (1970) 159.
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constituting a conflict of norms that we have just referred to ascontrary conflicts.11Obviously, it would be unconvincing to confirm or reject either of these definitions merely on the ground that it is not in linewith deontic logic, WTO jurisprudence or the ‘prevailing opinion’in international law doctrine. What then are decisive arguments?In order to answer this question, it is crucial to distinguishbetween two types of definitions, that is analytical definitions andstipulative definitions. An analytical definition analyses and explains the actual way a term is used in a given language.12 It is anassertion concerned with past or present usage and has truthvalue.13 A stipulative definition on the other hand establishes themeaning of a word. It takes the form of a command or proposal onthe meaning of a given term.14 This does not imply, however, thatthe author of a stipulative definition enjoys unrestricted discretion;he is bound in particular by teleological considerations. For purposes of legal doctrine this means above all that a stipulative definition must adequately fit into the legal system within which it ismeant to operate.15Turning back to the problem of how to define ‘conflict ofnorms’, it is arguably impossible to derive a complete and uniformanalytical definition from international legal texts. Hence, the definition to be introduced can only be stipulative and must, therefore,be teleologically adequate. The telos of norms is to regulate behaviour. It follows that if a given conduct is at the same time permittedand prohibited, it is not unequivocally but contradictorily regulatedfrom the viewpoint of the addressee of these norms. The same istrue for the other constellations discussed above. In other words, ifattaining this telos is impaired by a permissive norm incompatiblewith a prescriptive norm, one should recognize these norms as conflicting.11
12131415
As pointed out supra, in their view there is only a conflict of norms if‘a provision of the WTO Agreement mandates an action that a provision of another treaty prohibits or vice versa, when a provision of another treaty mandates an action that the WTO Agreement prohibits.’Klug (1982), 93; Weinberger (1989), 360-361.Dubislav (1981), 131.Cf Robinson (1968), 19, 21, 59-92; Klug (1982), 99-109; Weinberger(1989), 360-361.Klug (1982), 93; Weinberger (1989), 360.
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Thus, although the contrary position prevailing in internationallegal doctrine which is also held by Marceau and Tomazos cannotbe labelled as ‘incorrect’, it is teleologically inadequate. Above all,this approach disregards the fundamental interpretive requirementof investigating the actual consent of the contracting parties, inparticular in that it prevents the lex posterior and lex specialis principles from coming into play when a permission collides with aprohibition or obligation.16 This approach therefore passes overrelevant objective criteria such as the timing of treaties and thespecificity of norms. Ironically, the most pertinent critique has beenadvanced by the most distinguished advocate of this view: Jenkshad pointed out himself that incompatibilities between permissionsand prescriptive norms may ‘from a practical point of view be asserious’ as those between incompatible obligations, as such constellations ‘may render inapplicable provisions designed to give oneof the divergent instruments a measure of flexibility of operationwhich was thought necessary to its practicability’.17 This remarkhas not hindered his definition from finding its way into recentworks and, more strikingly, even into WTO jurisprudence.18 Still, itshould in itself be sufficient to cast into doubt the adequacy of thenarrow definition of conflict, which therefore should be rejected onthis ground and those just outlined.A concluding caveat must be issued in this context: international lawyers, in particular, are familiar with the notion that it isnecessary to distinguish conflicts according to the configurations ofthe parties involved. Thus, conflicts of norms may arise within onetreaty, between norms contained in two treaties with identical parties (AB/AB, ABCD/ABCD etc), between norms contained in two16
1718
It must be conceded that Gabrielle Marceau has held in one of herearlier writings on this subject that ‘[t]o take into account explicit‘rights’ provided in another treaty, one should refer to the lex specialis principle of interpretation’ (Marceau (2001) 1086). The lexspecialis principle, at least as employed by Marceau in her reasoning(ibidem 1086), constitutes a conflict rule; this is at odds with Marceau’s overall position that there is no conflict in such constellations.Jenks (1953), 426-427.Cf Marceau (2001); WTO panel report, Indonesia – Certain Measures Affecting the Automobile Industry, WTO Docs. WT/DS54/R,WT/DS59/R, WT/DS64/R, at footnote 649 (July 23, 1998); WTOpanel report, Turkey–Restrictions on Imports of Textile and ClothingProducts, WTO Doc. WT/DS34/R, paras 9.92-9.95 (May 31, 1999).
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treaties with decreasing or increasing membership (ABCD/AB,ABC/ABCD etc) or between norms contained in two treaties withoverlapping parties (AB/AC, ABCD/ABEF etc). On the one hand,the principles of lex specialis and lex posterior come into play ifthere is identity of parties (ie if states A and B have concluded twobilateral agreements that give rise to a conflict of norms). On theother hand, and more importantly, these principles may also applywhen the contracting parties to two agreements overlap (e.g. ifstates A and B have concluded a bilateral agreement, while they arealso parties to a multilateral agreement concluded by A, B, C andD); in the latter case, whether the more special or later-in-time bilateral treaty may be invoked depends on the pacta tertiis principle:in case there is a conflict, say from the perspective of A, betweenthe provisions of both agreements, A is prohibited from invokingthe AB treaty as a lex specialis or lex posterior in dispute settlementproceedings under the ABCD treaty, if the rights of the third partiesC and D would thereby be infringed. The same is true if A is partyto two bilateral agreements with B and C: if state A is under an obligation vis à vis state B to adopt a given behaviour b under oneagreement, and if state A is obligated at the same time towards stateC to adopt the irreconcilable conduct c under the other agreement,then there is a conflict from the viewpoint of state A. But state Acannot invoke its treaty with state B as a lex specialis or lex posterior to justify breaching its agreement with state C. The same holdstrue mutatis mutandis for its relation with state B: in such constellations, the pacta tertiis principle prevents state A from invoking thespecificity and timing of the conflicting treaty.19 These considerations are essential for the following issues.III. Jurisdiction and Applicable Law in WTO ProceedingsA. The Positions JuxtaposedPauwelyn has argued essentially that the respondent WTO Membercan invoke non-WTO rules of international law even within WTOproceedings, if certain conditions are fulfilled. First, such non-WTOrules must be binding on both parties (these are the ABCD/AB andABCD/ABEF constellations referred to above). Second, the establishment of such rules by way of an international agreement mustnot be prohibited by the WTO treaty (cf Art 41(1)(b) VCLT).19
Cf Art 30(4) lit b VCLT.
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Moreover, these rules may not affect the rights or obligations ofthird parties (cf Art 41(1) (b)(i) VCLT). Finally, the non-WTO ruleof international law must be shown to prevail over WTO law according to the established conflict principles of lex specialis and lexposterior.Pauwelyn argues that these principles also apply to the question whether non-WTO rules of international law have taken away apanel’s jurisdiction, the sole difference to issues of substantive lawbeing that this question may have to be addressed ex officio.While Marceau and Tomazos have not addressed the issue ofconflicts in substantive law which Pauwelyn has dealt with in hispresent paper, Gabrielle Marceau has held in widely noticed earlierpublications that panels cannot take account of inter se modifications of WTO law for lack of a ‘constitutional capacity’ to do so.Moreover, Marceau has insinuated that even inter se modificationsby WTO Members themselves may be impossible.20 In their presentpaper, Marceau and Tomazos essentially restate a stance recentlytaken by Kwak and Marceau,21 according to which ‘WTO adjudicating bodies always have the authority (and even the oblig