¹ In this article, I use “international authoritative soft law” to mean law that, while not necessarily formally binding on parties to a dispute, possesses attributes — namely the product of a process that is inclusive of the international community of states — that make it persuasive within negotiation discourse. See discussion at notes 66–90 and accompanying text.

² Convention on the Law of Non-Navigational Uses of International Watercourses, (1996) 36 I.L.M. 719 [Watercourses Convention].

³ Case Concerning the Gabčíkovo-Nagymaros Project (Hungary v. Slovakia), [1997] I.C.J. Rep. 92 (25 September) [Gabčíkovo-Nagymaros].

⁴ Cases include Lac Lanoux Arbitration (Spain v. France) (1957) 24 I.L.R. 101 (Arbitral Tribunal) [Lac Lanoux]; Fisheries Jurisdiction Case (Spain v. Canada), [1974] I.CJ. Rep. 3 [Fisheries Jurisdiction]; Gabčíkovo-Nagymaros, supra note 3; United States – Import Prohibition of Shrimps and Certain Shrimp Products, WTO Doc. WT/DS58/ AB/R (12 October 1998) [Shrimp-Turtle]; and Southern Bluefin Tuna Cases (Zealand v. Japan; Australia v. Japan), Provisional Measures, ITLOS No. 3 and 4 (1999). Treaties include Watercourses Convention, supra note 2 at sections 3(5) and 17; UN Convention on the Law of the Sea, (1982) 21 I.L.M. 1261, Articles 61, 62, 63, and 118 [LOSC]; UN Agreement Relating to the Conservation and Management of Straddling Fish Stocks and Migratory Fish Stocks, (1995) 34 I.L.M. 1542, Article 8(2) [Fish Stocks Agreement]. On the distinction between shared and common property natural resources, the former has been described as “a limited form of community interest, usually involving a small group of states in geographic continuity, who exercise shared rights over the resources in question,” for example, shared watercourses, while “common property resources, such as fisheries or mammals on the high seas, occur in areas beyond national jurisdiction where the resource is open to the use of all states and cannot be appropriated to the exclusive sovereignty of any state.” Birnie, P. and Boyle, A., International Law and the Environment (Oxford: Oxford University Press, 2002) at 139 Google Scholar and 141. The distinction is one without a difference for the purpose of this article, and I will refer to the term “shared natural resources” in relation to both.

⁵ Gabčíkovo-Nagymaros, supra note 3 at para. 141. While efforts are to be strong, there is no obligation to conclude an agreement. See Lac Lanoux, supra note 4 at 140; and United States – Import Prohibitions of Certain Shrimp and Shrimp Products, Recourse to Article 21.5 of the DSU by Malaysia, WTO Doc. WT/DS58/AB/RW (2001) at para. 123-24.

⁶ In Shrimp-Turtle, supra note 4 at para. 158, rights of environmental protection are to be exercised reasonably when it affects a treaty obligation (of non-discriminatory market access). In Gabčíkovo-Nagymaros, supra note 3 at para. 142, the International Court of Justice (ICJ) referred to the principle of good faith in Article 26 of the Vienna Convention on the Law of Treaties, (1969) 8 I.L.M. 68g [Vienna Convention]: “The principle of good faith obliges the Parties to apply [the treaty] in a reasonable way and in such a manner that its purpose can be realized.”

⁷ Gabčíkovo-Nagymaros, supra note 3 at para. 141 (bargaining is to be “meaningful”); and Lac Lanoux, supra note 4 at 140 (conflicting interests in a shared watercourse to be reconciled “by mutual concessions”).

⁸ Fisheries Jurisdiction, supra note 4 at para. 69 (“an equitable solution derived from the applicable law”); Gabčíkovo-Nagymaros, supra note 3 at para. 141 (parties to find an agreed solution that takes into account “norms of international environmental law and the principles of the law of international watercourses”).

⁹ Irvin, J. K., “The Role of Law in the Negotiated Settlement of International Disputes” (1969) 3 Vanderbilt International 58 Google Scholar at 70 (where there is “a sophisticated and large body of applicable legal rules of law, decisions based on such law, whether made by adjudicators or negotiators, would be easier and distortion of legal arguments would be more difficult”).

¹⁰ Under the Vienna Convention, supra note 6, for example, good faith may mean simply that states not act in bad faith, for example, the prohibition against inducing states to conclude a treaty by fraudulent conduct under Article 49. Or good faith may have more proactive content, such as Article 26, which requires treaty obligations to be performed in good faith, meaning a reasonableness standard. See Gabčíkovo-Nagymaros, supra note 3.

¹¹ Rosenne, S., Developments in the Law of Treaties 1945-1986 (Cambridge: Cambridge University Press, 1989) at 175 Google Scholar (referring to the general role of good faith in decision-making, whether in a second or third-party context). For more discussion on this point, see Hutchison, C. “The Duty to Negotiate International Environmental Law Disputes in Good Faith” (2006) 2 McGill Int’l J. Sustainable Development L. & Pol’y [forthcoming].Google Scholar

¹² For example, the number and types of actors involved, the number and complexity of issues under consideration, the structure and timelines within which negotiations occur, and the strategies and approaches that parties may employ. For a general overview of these issues, see Starkey, B.,Boyer, M., and Wilkenfeld, j., Negotiating a Complex World: An Introduction to International Negotiation (Lanham, MD: Rowman and Littlefield, 1999).Google Scholar

^l3 See, e.g., Sjostedt, G., “Preface,” in Sjostedt, G., ed., International Environmental Negotiations (Newbury Park: Sage, 1993) at xiv.Google Scholar

¹⁴ Hurrell, A. and Kingsbury, B., eds., The International Politics of the Environment: Actors, Interests and Institutions (Oxford: Clarendon Press, 1992) at 19.Google Scholar

¹⁵ See Faure, G. O. and Rubin, J. Z., “Organizing Concepts and Questions,” in Sjostedt, G., ed., International Environmental Negotiation (Newbury Park: Sage 1993), 22.Google Scholar

¹⁶ Tenbrunsel, A. E., “Trust as an Obstacle in Environmental-Economic Disputes” (1999) 42 Am. Behavioural Scientist 1354.CrossRefGoogle Scholar

¹⁷ Cooper, C., “The Management of International Environmental Disputes in the Context of Canada-US Relations: A Survey and Evalutation of Techniques and Mechanisms” (1986) 24 Can. Y.B. Int’l L. 252.Google Scholar

¹⁸ Sjostedt, supra note 13 at xiv.

¹⁹ See R.E. Benedick, “Perspectives of a Negotiation Practitioner,” in Sjostedt, ed., supra note 13, 220.

²⁰ Bilder, R. “The Settlement of Disputes in the Field of the International Law of the Environment” (1976) 144 Ree. des Cours 155 Google Scholar. As well, international environmental problems often involve multiple victims and multiple sources.

²¹ Benedick, supra note 19 at 219, referring to projected effects of climate change.

²² Bilder, supra note 20 at 154.

²³ Or states “free ride” on costly environmental protection regimes. See Susskind, L. E., Environmental Diplomacy: Negotiating More Effective Global Agreements (Oxford: Oxford University Press, 1994) at 18–24.Google Scholar

²⁴ Rio Declaration on Environment and Development, 13 June 1992, (1992) 31 I.L.M. 874 [Rio Declaration!, Principle 19: “States shall provide prior and timelynotification and relevant information to potentially affected States on activities that may have a significant adverse transboundary environmental effect and shall consult with those States at an early stage and in good faith.” According to Sands, P., Principles of International Environmental Law, 2nd edition (Cambridge: Cambridge University Press, 2003), Principle 19 is part of customary international law.CrossRefGoogle Scholar

²⁵ Obligations of information exchange, prior notification, and consultation are viewed as dispute avoidance mechanisms, “designed to increase cooperation generally, identify potential conflicts as they are emerging, build confidence between the parties, or otherwise assist in allowing the parties to avoid and prevent disputes before they arise.” Hunter, D., Salzman, J., and Zaelke, D., International Environmental Law and Policy (New York: Foundation, 1998) at 495–96.Google Scholar

²⁶ Wolfrum, R., “International Law of Cooperation,” in Encyclopedia of Public International Law, volume 2 (Amsterdam: Elsvier, 1995), 1242.Google Scholar

²⁷ The duty to negotiate in good faith as an obligation of cooperation is clear from the case law listed in note 4), though its precise nature has been noted to be unclear. See Dupuy, P. M., “The Place and Role of Unilateralism in Contemporary International Law” (2000) 11 Eur. J. Int’l L. 23 Google Scholar: “The relationship between the obligation to cooperate and the obligation to negotiate remains to be clarified, with the latter in reality appearing as one of the translations of the former, certainly the most immediate one.” See also McCaffrey, S., The Law of International Watercourses, Non Navigable Uses (Oxford: Oxford University Press, 2001) at 402 Google Scholar, who refers to the Lac Lanoux arbitration: “[T]he tribunal also illustrates how a state could be shown to break its obligation to cooperate, when cooperation takes the specific form of negotiating in good faith with a view to reaching an agreement.”

²⁸ The cost, construction, and operation of the project were to be borne in equal measure by the parties. Gabčíkovo-Nagymaros, supra note 3 at para. 18.

²⁹ Treaty Concerning the Construction and Operation of the Gabčíkovo-Nagymaros System of Locks, 32 I.L.M. 1247 (1993) [1977 Treaty], Article 15: The parties “shall ensure, by means specified in the joint contractual plan, that the quality of the water in the Danube is not impaired as a result of the construction and operation of the System of Locks.” Article 19: The parties “shall, through the means specified in the joint contracttial plan, ensure compliance with the obligations for the protection of nature arising in connection with the construction and operation of the System of Locks.” Article 20: The parties are to “take appropriate measures within the framework of their natural investments, for the protection of fishing interests in conformity with the Convention Concerning Fishing in the Waters of the Danube.”

³⁰ Gabčíkovo-Nagymaros, supra note 3 at para. 31. The Gabčíkovo sector was 70-95 percent complete on various projects.

³¹ Ibid, at para. 32.

³² Ibid, at para. 40.

³³ Ibid, at para. 35. The study of environmental impacts was not certain and would require “time-consuming studies.”

³⁴ Ibid, at 225, per Vereshchetin J. (dissenting).

³⁵ Ibid, at para. 37.

³⁶ Ibid, at para. 61.

³⁷ Ibid, at para. 37.

³⁸ This may have marked the point of no return in terms of a negotiated outcome, according to Fleischhauer J. Ibid, at 209.

³⁹ Ibid, at para, 91.

⁴⁰ Ibid, at para. 65.

⁴¹ Ibid, at para. 48.

⁴² Ibid, at para. 78.

⁴³ Ibid, at para. 89 ff.

⁴⁴ See Romano, C. P. R., The Peaceful Settlement of International Environmental Disputes: A Pragmatic Approach (The Hague: Kluwer, 2000) at 259—60.Google Scholar The author notes the “dogged defense” of the 1977 Treaty, notwithstanding the “continuous and reciprocal disregard” by both parties. However, upholding of a treaty was to be expected since the parties under the compromis put the focus on the 1977 Treaty.

⁴⁵ Gabčíkovo-Nagymaros, supra note 3 at para. 135. But see Romano, ibid, at 249. While the 1977 Treaty did not establish a priority for any one objective, “even a superficial reading of it showed the primacy of the hydroelectric element over the others.”

⁴⁶ Gabčíkovo-Nagymaros, supra note 3 at para. 139.

⁴⁷ Ibid, at para. 141.

⁴⁸ Ibid, at para. 44.

⁴⁹ Ibid, at para. 138. While the proposed dams and canals were the subject of the 1977 Treaty, peak power operation was not in the treaty but could be negotiated under joint contractual plan that implemented the technical requirements of the treaty obligations.

⁵⁰ Bilder, R., “The Role of Unilateral State Action in Preventing International Environmental Injury” (1981) 14 Vand. J. Transnat’l L. 53 Google Scholar, defines unilateral state action as “any action which a state takes solely on its own, independent of any express co-operative arrangement with any other state or international institution.” On the negative effects of unilateral measures on state cooperation, see de Chazournes, Boisson, “Unilateralism and Environmental Protection: Issues of Perception and Reality of Issues” (2000) 11 Eur. J. Int’l L. 320 Google Scholar, suggesting they lack legitimacy based on their individualistic nature [judge in its own cause] and tend to be a hegemonic weapon of powerful states.

⁵¹ See Collier, J. and Lowe, A. V., The Settlement of Disputes in International Law: Institutions and Procedures (Oxford: Oxford University Press, 1999) at 8 Google Scholar: “[T]he disputing parties perceptions of the strength of their respective legal arguments is a major factor influencing the outcome of the negotiations or the decision to move from negotiation to some other form of dispute settlement.”

⁵² States generally do not consent to the compulsory jurisdiction of international courts and tribunals, preferring instead to preserve their freedom of action and maintain control over the outcome of dispute resolution. In environmental disputes, there are added reasons not to go to court. See Birnie and Boyle, supra note 4 at 178-79.

⁵³ Chayes, A. and Chayes, A. Handler, The New Sovereignty: Compliance loith international Regulatory Agreements (Cambridge, MA: Harvard University Press, 1995)Google Scholar. The starting point of this work is that states do not tend to intentionally flout their legal commitments but, to the extent that they do not comply, it is frequently related to problems of incapacity, ambiguity in treaty language, and/or transitional (or temporal) factors.

⁵⁴ Ibid, at 25-26. The concept of “justificatory discourse” resembles the requirement of “rational discussion” with respect to good faith negotiation in Canadian labour relations law. One corollary of rational discussion is that parties justify the negotiating positions that they take. The premise here is that parties can meaningfully negotiate and more likely reach agreement if they engage in a rational discussion, as opposed to hard bargaining. An employer or union cannot during good faith bargaining, for example, insist on their own interpretation of the law and refuse to discuss other interpretations. See Adams Canadian Labour Law, looseleaf (Aurora: Canada Law Book, 2003) at 10-93 ff and B. Adell, “The Duty to Bargain in Good Faith: Its Recent Development in Canada,” paper presented at the twenty-eighth Annual Conference of the McGill University Industrial Relations Centre, March 1980, Queens University Industrial Relations Centre, No. 48.

⁵⁵ Chayes and Handler Chayes, supra note 53 at 8.

⁵⁶ Ibid, at 12.

⁵⁷ Ibid, at 122.

⁵⁸ Ibid, at 26-27. The success of the managerial process is assured through the “new sovereignty,” where states, if they are to realize their own interests in an interdependent world, must “submit to the pressures of international regulation” in order to maintain their membership in good standing within regimes and in the international community.

⁵⁹ See Bodansky, D., “Symposium: Customary (and Not So Customary) International Environmental Law” (1995) 3 Ind. J. Global Leg. Stud. 105 Google Scholar, who argues that it is better to view international environmental norms not as how states behave but in how states speak to one another. This “declarative law” acts as “evaluative standards used by states to justify their actions and to criticize the actions of others” (at 115). Recognizing the dearth of third-party dispute resolution in international law, Bodansky views inter-state negotiation as the forum for declarative law and in this context (as opposed to adjudication) the legal status of a norm is not critical to its influence. In this regard, it has been documented in several cases that emanation of soft law norms from accepted channels has facilitated the resolution of international disputes. Others have also noted that the form of the instrument is not determinative of its influence. See Chinkin, C., “Normative Development in the International Legal System,” in Shelton, D.,ed., Commitment and Compliance: The Role of Non-Binding Norms in the International Legal System (Oxford: Oxford University Press, 2000) at 37 Google Scholar; D. Shelton, “Law, Non Law and the Problem of ’Soft Law,’” in Shelton, ed., ibid, at 11; and Brunnée, J. and Toope, S J., “The Changing Nile Basin Regime: Does Law Matter?” (2002) 43 Harv. Int’l L.J. 148.Google Scholar

⁶⁰ Mavrommatis Palestine Confession, (1924) P.C.I J. (Ser. A) No. 2, 12.

⁶¹ Draft Articles on the Law of the Non-Navigational Uses of International Watercourses, infra note 80, Article 7(2), which requires consultation when an affected state is caused significant harm despite the exercise of due diligence, indicates that when consultations fail to lead to a solution, the Article 33 dispute settlement procedures (including negotiation) will apply. See also Tanzi, A. and Arcari, M. The United Nations Convention on the Law of International Watercourses (The Hague: Kluwer Law, 2001) at 123 Google Scholar. The term “consultation” is employed in Article 6(2) since it was believed “negotiation” necessitated the existence of a dispute possibly requiring dispute settlement procedures, when instead dispute avoidance was the aim of the provision.

⁶² Statute of the International Court of Justice, in Brownlie, I.. ed., Basic Documents in International Law, 3rd edition (Oxford: Clarendon Press, 1983) at 387 Google Scholar. Article 38(1) also refers to general principles of law and, as subsidiary sources, judicial decisions, and the teachings of highly qualified publicists.

⁶³ “Treaty” is defined as “an international agreement concluded between States in written form and governed by international law, whether embodied in a single instrument or in two or more related instruments and whatever its particular designation. Vienna Convention, supra note 4, Article 2(1) (a).

⁶⁴ Custom need not be based on universal state practice and opinio juris, but there should be widespread participation including states whose interests are specially affected. Brownlie, I. , Principles of Public International Laxo, 5th edition (London: Clarendon Press, 1998) at 6.Google Scholar

⁶⁵ It is possible though not common, however, for custom to arise within a short period provided certain stringent conditions are met. See Case Concerning North Sea Continental Shelf (Federal Republic of Germany v. Denmark; Federal Republic of Germany v. Netherlands), [1969] I.C.J. Rep. 3 (20 February) at para. 73.

⁶⁶ Thurer, D., “Soft Law,” in Encyclopedia of Public International Law, volume 4 (Amsterdam: Elsevier, 2000), 452 Google Scholar. See also Chinkin, supra note 59 at 30, which provides a more comprehensive list of law that may be considered soft law: articulation in a non-binding form; terms that are vague and imprecise; the declaring body lacks international law-making authority; law directed at non-state actors; law without a “corresponding theory of responsibility”; and law based on voluntary adherence or non-judicial means of enforcement. See also Boyle, A., “Some Reflections on the Relationship of Treaties and Soft Law” (1999) 48 I.C.L.Q. 901 CrossRefGoogle Scholar, which identifies three possible meanings: soft law as non-binding; soft law as principles, not rules; and soft law as law that is not enforceable through binding dispute resolution.

⁶⁷ Indeed, some writers have rejected as oxymoron the possibility of law as not being coextensive with legal obligation. See Thurer, supra note 66 at 456.

⁶⁸ See D. Shelton, supra note 59 at 12-13; Chinkin, supra note 59 at 30-31 and4i; and A. Kiss, “Commentary and Conclusions,” in Shelton, ed., supra note 59, 237. Some other purposes of soft law are to avoid domestic legislative and constitutional barriers to treaty ratification and/or permit ease of amendment or termination and to elaborate upon hard law obligations.

⁶⁹ Where there is uncertainty in technical knowledge, soft law is an appropriate means “to formulate shared expectations at a lower level.” Thurer, supra note 66 at 453.

⁷⁰ Rio Declaration, supra note 24.

⁷¹ Soft law does this in a way that traditional forms of law-making — that is, custom and hard treaty commitments — are incapable of addressing, for example, in the way soft law influences state behaviour, sets negotiating agendas, and supplements and shades existing obligations. Chinkin, supra note 59 at 41.

⁷² Ibid, at 42.

⁷³ Thurer, supra note 66 at 453.

⁷⁴ Ibid, at 454.

⁷⁵ These criteria of law’s persuasive attributes are from Chayes and Handler Chayes, supra note 53 at 116.

⁷⁶ Thurer, supra note 66 at 457: “[T]he principle of good faith … has the effect that expectations produced by [soft law] are legally protected insofar as they are justified by the conduct of the parties concerned.”

⁷⁷ Commonwealth of Australia v. The State of Tasmania, (1983) 158C.L.R. 1 (Australian Supreme Court). Convention for the Protection of the World Cultural and Natural Heritage, 11 I.L.M. 1358 (1972).

⁷⁸ Chinkin, C. M., “The Challenge of Soft Law: Development and Change in International Law” (1989) 38 I.C.L.Q. at 866 CrossRefGoogle Scholar. See also Schachter, O., Sharing the World’s Resources (New York: Columbia University Press, 1977) at 3–4 Google Scholar: “Whether or not they [referring to declarations, charters and resolutions of UN organizations] are accepted as international legal rules, they are likely to engender expectations about future patterns of international distribution, and, in some cases, to delegitimize traditional norms which would otherwise be regarded as authoritative.”

⁷⁹ Thurer, supra note 66 at 459. See also Baxter, R., “International Law in ’Her Infinite Majesty’” (1980) 29 I.C.L.Q. 565 CrossRefGoogle Scholar (soft law as establishing a legal frame-work to guide negotiations).

⁸⁰ Draft Articles on the Law of the Non-Navigational Uses of International Watercourses, International Law Commission 46111 Session, Yearbook of the International Law Commission (1994), volume 2, Part 2, in Watts, A., ed., The International Law Commission 1949-1998, volume 2 “The Treaties,” Part II (Oxford: Oxford University Press, 1999) at 1332 Google Scholar [Draft Articles on Watercourses]. The Watercourse Convention was adopted through the UN General Assembly “without substantially departing from” the final ILC articles.

⁸¹ Statute of the International Law Commission, Article 13 (1) (a) of the Charter of the United Nations, in Anderson, M. R. et al., eds., The International Law Commission and the Future of International Law (London: British Institute of International and Comparative Law, 1998), 55 [ILC Statute].Google Scholar

⁸² ILC Statute, ibid., Article 15.

⁸³ Ibid., Article 8. See also M.R. Anderson and C. Wickremasinghe, “Introduction,” in Anderson et al., eds., supra note 81 at xv.

⁸⁴ Schwebel, S. M., “The Influence of the International Court of Justice on the Work of the International Law Commission and the Influence of the Commission on the Work of the Court,” in Making Better International Law: The International Law Commission at Fifty (New York: United Nations, 1998) at 161 Google Scholar. See also ILC Statute, supra note 81, Articles 16 and 17.

⁸⁵ Birnie and Boyle, supra note 4 at 22. And indeed, the ICJ in the Gabčíkovo-Nagymaros case, supra note 3, explicitly relied on the work of the ILC in four areas of law: treaties, state succession, state responsibility, and international watercourses.

⁸⁶ A.E. Boyle and A.V. Lowe, “Report of the Study Group on the Future Work of the International Law Commission,” in Anderson et al., eds., supra note 81 at 14.

⁸⁷ Ibid, at 22-23

⁸⁸ Ibid.

⁸⁹ Handl, G. “A Hard Look at Soft Law” (1988) 82 A.S.I.L. Proc. 371 Google Scholar. Soft law can be an expression of emerging notions of public international order — a basis for establishing “legitimate international concern” in areas that were previously the exclusive domain of state sovereignty. Further, soft law reflects a paradigm shift of “communality of purpose” as a result of deepening global interdependencies in international security, environmental, and economic mat-ters.

⁹⁰ CM. Chinkin, in Handl, supra note 89 at 391.

⁹¹ Byers, M., “Abuse of Rights” (2002) 47 McGill LJ. 417 Google Scholar, referring to reasonableness standard in international law, “(c)onstructing a hypothetical ’man on the Clapham omnibus’ requires a degree of cultural and situational commonality that has traditionally not been present among many of the states that make up the international community.”

⁹² Birnie and Boyle, supra note 4 at 146-47, referring to the principle of equitable utilization of watercourses. Interpreting the exercise of rights on the basis of state practice was also suggested by Sir Hersh Lauterpacht in the context of discussing the limits placed on rights under abuse of right doctrine. See Brownlie, supra note 62 at 296 and 305.

⁹³ Lac Lanoux, supra note 4 at 150.

⁹⁴ Franck, T. M., Fairness in International Law and Institutions (Oxford: Clarendon Press, 1995) at 30–45.Google Scholar

⁹⁵ Ibid, at 37.

⁹⁶ On this last point, it is interesting to note that Franck’s discussion of the draft Watercourse Convention (as it then was) suggests that there “is no reason why these standards (of the convention) cannot be appliedjust as effectively as standards found in more traditional normative rules.” Ibid, at 75.

⁹⁷ Discussed in Brunnée, j. and Toope, S. J., “International Law and Constructivism: Elements of an Interactional Theory of International Law” (2000) 39 Colum. J Transnat’l L. 45.Google Scholar

⁹⁸ Ibid, at 54.

⁹⁹ Ibid, at 53.

¹⁰⁰ Ibid, at 54.

¹⁰¹ Fuller, L., The Morality of Lain, 2nd edition (New Haven, CT: Yale University Press, 1969) at 33 ff.Google Scholar

¹⁰² Brunnée and Toope, supra note 9,7 at 56.

¹⁰³ Brunnée, J., “COPing with Consent: Law-Making under Multilateral Environmental Agreements” (2002) 15 Leiden J. Int’l L. 36.Google Scholar

¹⁰⁴ Brunnée, J. and Toope, S. J., “Persuasion and Enforcement: Explaining Compliance with International Law” (2002) 13 Finnish Y.B. Int’l L. 273 Google Scholar.

¹⁰⁵ Brunnée, supra note 103 at 44.

¹⁰⁶ Ibid. “Frequently, they will be in a dynamic relationship and will require lawmakers to strike a balance between them,”

¹⁰⁷ Ibid, at 46.

¹⁰⁸ I do not include here the criterion of “relative predictability” since the arduous process of negotiation between a global community of states ensures that these instruments do not arise frequently.

¹⁰⁹ On equitable utilization, see Article 5 of Watercourses Convention, supra note 2, and ILC commentary in Draft Articles on Watercourses, supra note 80 at 1352 ff, in particular para. (8). On the no significant harm principle, see Principle 2 of the Rio Declaration, supra note 24.

¹¹⁰ Expression is given to environmental protection, though in the view of some writers, it does not go far enough in incorporating international environmental law. See Hey, E., “The Watercourses Convention: To What Extent Does It Provide a Basis for Regulating Uses of International Watercourses? (1998) 7 R.E.C.I.E.L. 291.Google Scholar

¹¹¹ Draft Articles on Watercourses, supra note 80 at 1353. Sustainable use, while referred to in the article’s commentary, was included in the text of the Water-course Convention. One criticism of this formulation of sustainable use is that it is not specific enough in its requirements. States therefore have much discre-tion in giving effect to sustainable use. Furthermore, when states dispute conflicting uses, the question becomes not whether the use is sustainable, but sustainable for what purpose? See Birnie and Boyle, supra note 4 at 89 and 318.

¹¹² Draft Articles on Watercourses, supra note 80 at 1353. Adequate protection of the watercourse is broadly defined to include conservation, water-related disease, or security concerns as well as issues such as regulating flow and controlling floods. A specific application of adequate protection is Article 20, which formulates an obligation to “individually or jointly, protect and preserve the ecosystems of international watercourses” (at 1397). This essentially requires states to “shield” international watercourse ecosystems from harm or damage. The duty to “preserve” is made principally in relation to freshwater ecosystems in “pristine and unspoiled condition.” The duty to protect and preserve ecosystems assists in ensuring the continued viability of freshwater ecosystems as life support systems, “thus providing an essential basis for sustainable development” (at 1397). The standard of Article 20 is one of due diligence.

¹¹³ Ibid, at 1353-54. Equitable participation “flows from, and is bound up with, the rule of equitable utilization.”

¹¹⁴ Ibid, at 1354. Optimal use “implies attaining maximum possible benefits for all watercourse states and achieving the greatest possible satisfaction of all their needs, while minimizing the detriment to, or unmet needs of, each” and “the attainment of optimal utilization and benefits entails cooperation between watercourse states through their participation in the protection and development of the watercourse.” “[T]he failure of a state to negotiate and cooperate in good faith with its co-riparians in order to co-ordinate their respective interests … will make it difficult for that State to claim that its planned or actual use is ’optimal’ and, therefore, equitable under Article 5 of the Convention.” Tanzi and Arcari, supra note 61 at 109, suggest that the goal of optimal utilization in Article 5 implies a duty of cooperation. “Obviously, then, for a state to ensure that its own use is equitable or reasonable, it must be provided with a variety of kinds of data and information by its co-riparians,” otherwise it would be forced to make a “blind assessment.” McCaffrey, supra note 27 at 342. “[T]he obligation of equitable and reasonable utilization depends ultimately on good faith and ongoing cooperation between the states concerned” (at 343). See also Article 6(2), which requires states shall “when the need arises, enter into consultations in a spirit of cooperation.”

¹¹⁵ Draft Articles on Watercourses, supra note Ho at 1362. “[Protection” is used in the same sense as stated in note 1 12 of this article; “conservation” is defined as measures relating to conservation and management, degradation of water quality, and supraotably pollution), as well as to living resources, flood control, erosion, sedimentation, and salt water intrusion.

¹¹⁶ Tanzi and Arcari, supra note 61 at 124.

¹¹⁷ Draft Articles on Watercourses, supra note 80, Article 10(2).

¹¹⁸ Ibid, at 1379, the commentary cross-references this to Article 6(i)(b).

¹¹⁹ Principle 2 of Rio Declaration, supra note 24.

¹²⁰ Kaya, I., Equitable Utilization: The Law of the Non-Navigational Uses of International Watercourses (Aldershot, UK: Ashgate, 2003) at 157.Google Scholar

¹²¹ Draft Articles on Watercourses, supra note 80 at 1365. One writer attributes to due diligence “a minimum standard of conduct … usually measured by an emerging set of procedural rules on the conduct of States,” which includes, in the watercourse context, exchange of information, notification of planned measures as well as consultation and negotiation. See Hanquin, Xue, Transboundary Damage in International Law (Cambridge: Cambridge University Press, 2003) at 165–75.Google Scholar Gabčíkovo-Nagymaros, supra note 3 at para. 140, infers a duty to continually monitor the environmental impacts of projects, which arguably may form a part of due diligence in watercourse law. The case cannot be viewed as definitively staking out a place for the “no significant harm” rule vis-à-vis equitable utilization. Some commentators, however, take the view that the court implicitly rejected priority to the rule. The ICJ in Gabčíkovo-Nagymaros rejected Hungary’s “invitation to apply a no harm rule,” stating that the court made a number of references to general international law. McCaffrey, supra note 27 at 359. The court did not endorse the principle in its decision, “giving no credibility to the notion of the existence of a ‘no significant harm’ rule that qualifies the principle of equitable utilization.” Bourne, C. B., “The Case Concerning the Gabčíkovo-Nagymaros Project: An Important Milestone in International Water Law” (1997) 8 Y.B. Int’l Envtl. L. 10.Google Scholar

¹²² McCaffrey, supra note 27 at 379, concludes that for the no significant harm obligation to be breached, three conditions must be met: significant harm must result; the acting state must have been capable of preventing the harm by other conduct; and the conduct must be unreasonable in all the circumstances (at 367). He emphasizes “significant harm” as a threshold that triggers discussions (whether consultations or negotiations) to review the extent of the harm and whether it is reasonable for the affected state to insist on being free from the harm. Environmental harm forms part of equitable balancing only where harm is less than “significant” or where harm is significant but unavoidable even through the exercise of due diligence. Birnie and Boyle, supra note 4 at 30910. See Brunnee, J. and Toope, S. J., “Environmental Security and Freshwater Resources: Ecosystem Regime Building” (1997) 91 Am. J. Int’l L. 26 CrossRefGoogle Scholar, who add an extra element of procedural caution, suggesting a shifting of the burden in that even where significant harm will result despite the exercise of due diligence, the use will be “prima facie inequitable.”

¹²³ Draft Articles on Watercourses, supra note 80 at 1368.

¹²⁴ “[T]he obligation to prevent pollution that may cause significant harm includes the duty to exercise due diligence to prevent the threat of such harm.” And, later in the same paragraph, reduce and control pollution is said to relate to cases where pollution of the watercourse already exists, indicating “a general willingness to tolerate even significant pollution harm, provided that the watercourse State of origin is making its best efforts to reduce the pollution to a mutually acceptable limit.” Ibid, at 1403. See also Brunnée and Toope, supra note 122 at 63; Birnie and Boyle, supra note 4 at 307; and McCaffrey, supra note 27 at 386.

¹²⁵ From Kaya, supra note 120 at 161-62.

¹²⁶ Draft Articles on Watercourses, supra note 80 at 1 389. The notified state, under Article 15, is to communicate its findings, and provide detailed explanations should it conclude the planned measure would be inconsistent with Article 5 (equitable utilization) or Article 7 (the no harm rule). Importantly for cases of scientific uncertainty, the ILC commentary suggests that the word “would” is used rather than “might” because “the notified state must conclude that a violation of articles 5 or 7 is more than a mere possibility.”

¹²⁷ Ibid, at 1392 (commentary to Article 17).

¹²⁸ The Fish Stocks Agreement, supra note 4, was adopted by consensus including all major distant water and coastal fishing states. Birnie and Boyle, supra note 4 at 673. There were fifty-two ratifications as of May 2005. See <http://www.un. org/Depts/los/reference_files/c h ronological_l is ts_of ratifications. htm#AgreementfortheimplementationoftheprovisionsoftheConvention relatingtotheconservationandmanagementofstraddlingfishstocksandhighly migratoryfishstocks> (26 June 2005). Article 7 of the Fish Stocks Agreement explicates legitimate interests in fish stocks conservation.

¹²⁹ One legal issue that is still unresolved in the international trade jurisprudence is whether rights of environmental protection under Article XX of the General Agreement on Tariffs and Trade, 30 October 1947, 55 U.N.T.S. 194, can be asserted outside of a state’s jurisdiction — that is, whether the right to take measures under Article XX (g) “relating to the conservation of exhaustible natural resources if such measures are made effective in conjunction with restric-tions on domestic production or consumption” extends to environmental protection concerns outside of a state’s jurisdiction. In two cases, United States – Restrictions on Imports of Tuna, 39 GATT B.I.S.D. 155 (1993), reprinted in 30 I.L.M. 1594 (1991), panels came to different conclusions on the issue. In Shrimp-Turtk, supra note 4 at para. 133, the Appellate Body held that, because the sea turtle species being regulated occur at times within US waters, “there is a sufficient jurisdictional nexus between the migratory and endangered marine populations involved and the United States for the purposes of Article XX (9).” A wider conception of law, as advanced through legitimacy criteria, may help resolve this controversy. Widely ratified global conservation treaties identify a legitimate interest of the international community in endangered species protection, regardless of location, as a matter of common concern, for example, the preamble to the Convention on Biological Diversity, (1992) 31 I.L.M. 822 [CBD], identifies the conservation of biological diversity as “a common concern of humankind” (at preamble, recital 3). The Convention on International Trade in Endangered Species of Wild Fauna and Flora, (1973) 12 I.L.M. 1085, recognizes that wild fauna and flora must be protected for future generations and lists most migratory sea turtles as “species threatened with extinction” (at preamble, recital 1). The Convention on Conservation on the Conservation of Migratory Species of Wild Animals, (1980) 19 I.L.M. 15 [CMS Convention], recognizes that wild animals are to be conserved for “the good of mankind” and for future generations (at preamble, recital 1 and 2).

¹³⁰ See Shrimp-Turtle, supra note 4 at para. 130. The Appellate Body looked to modern international environmental treaties and instruments, most of which the United States was not a party to — LOSC, supra note 4; CMS Convention, supra note 129; CBD, supra note 129; and Agenda 21, 13 June 1992, UN Doc. A/CONF. 151/ 26 (1992) — to support an interpretation of exhaustible natural resources as including living natural resources.

¹³¹ Vicuna, Francesco Orrego , The Changing international Law of High Seas Fisheries (Cambridge: Cambridge University Press, 1999) at 2–3 Google Scholar: “Important as cooperation is, it nonetheless rests on weak grounds since it assumes a degree of good will and spirit of accommodation that is not always available among highly competitive entities … In addition this co-operative approach has been one of the important flaws in the historical experience of international law (of high seas fisheries).”

¹³² States acting unilaterally are rarely opposed to the principle of multilateralism. Bilder, supra note 50 at 91.