1.1 Introduction
As sovereign entities in pursuit of their domestic and foreign policy objectives, States invariably fall into dispute. The existence of disputes is not in and by itself a weakness of the international society – in fact, disputes can be an indicator of a vibrant, energetic, and healthy society.Footnote 1 That said, disputes run the risk of disrupting international relations and creating threats to international peace and security.Footnote 2 What is critical is that the international society puts in place measures, mechanisms, and means to ensure that disputes are resolved peacefully. Indeed, where disputes are settled peacefully this can be a driver of positive change within the international society, for example, by forging a closer sense of community between its members and by developing new norms and rules that set acceptable standards of behaviour.Footnote 3
In order to maintain international peace and security, States have developed a range of political and legal methods to facilitate the peaceful settlement of their disputes, including negotiation, conciliation, mediation, and arbitration, among others.Footnote 4 One of the cornerstones of this system is the obligation to settle disputes peacefully.Footnote 5
The scholarship on peaceful dispute settlement has traditionally adopted an ‘institutional’ approach to the subject,Footnote 6 with its focus being on the means and methods that can be used to settle disputes rather than on the substance of the peaceful settlement obligation itself. The reason for this is because the obligation to settle disputes peacefully is usually seen as the flip side of the prohibition on the threat or use of force,Footnote 7 meaning that the peaceful settlement obligation does no more than require States to refrain from the threat or use of force when seeking to resolve disputes. By effectively flattening the obligation to settle disputes peacefully into a reiteration of the duty to avoid force in international relations, this approach precludes an in-depth investigation into the content of the obligation of peaceful dispute settlement as an autonomous rule of international law.
This chapter rejects the conflation of the principles of non-use of force and peaceful dispute settlement and separates them out by examining the status, nature, content, scope, and consequences of the latter. In doing so, this chapter adheres to the following structure: Section 1.2 traces the emergence of the obligation of peaceful dispute settlement under international law and establishes its status as a binding rule of treaty and customary law. Section 1.3 examines the conditions for the engagement of the obligation to settle disputes peacefully. Section 1.4 explores what measures disputants must take in order to discharge their obligation to settle disputes peacefully. This section argues that the obligation of peaceful dispute settlement is dynamic in nature and, as such, the conduct it requires from disputing parties varies depending on the circumstances of each case. This section also shows that the obligation operates as an interstitial norm insofar as it influences the interpretation and application of other rules of international law relevant to the peaceful settlement of disputes. Section 1.5 offers some concluding remarks on the utility of the obligation of peaceful dispute settlement in contemporary international relations.
1.2 The Obligation of Peaceful Dispute Settlement: History and Status
The obligation of peaceful dispute settlement has a long history in international law and can be traced back at least as far as the 1899 Hague Convention on the Peaceful Settlement of Disputes.Footnote 8 This Convention requires State parties ‘to use their best efforts to insure the pacific settlement of international differences’Footnote 9 and identifies a range of methods they can use to help settle their disputes peacefully, including good offices, commissions of inquiry, mediation, and arbitration.Footnote 10
The obligation of peaceful dispute settlement has been confirmed in numerous treaties since the adoption of the Hague Convention in 1899.Footnote 11 Given its (almost) universal membership, the United Nations (UN) is most significant in this regard. Article 1 of the Charter sets out the UN’s overarching aims and objectives and, according to Article 1(1), one of its main purposes is to
maintain international peace and security, and to that end … to bring about by peaceful means, and in conformity with the principles of justice and international law, adjustment or settlement of international disputes or situations which might lead to a breach of the peace.Footnote 12
While Article 1 identifies the UN’s purposes, Article 2 enumerates its guiding principles and, with a view to maintaining international peace and security, Article 2(3) of the Charter provides that ‘all Member States shall settle their international disputes by peaceful means in such a manner that international peace and security, and justice, are not endangered’.
Article 2(3) is framed in binding terms: by using the imperative ‘shall’, UN members must settle their disputes peacefully as a matter of international law.Footnote 13 Article 33(1) of the UN Charter – located in Chapter VI titled ‘Pacific Settlement of Disputes’ – reaffirms the obligation upon member States to settle their disputes peacefully (again, note Article 33(1)’s use of the imperative ‘shall’) and provides a list of political and legal methods they can use to help realise this objective.Footnote 14 Article 33(1) therefore ‘complements’Footnote 15 Article 2(3) and reads:
The parties to any dispute, the continuance of which is likely to endanger the maintenance of international peace and security, shall, first of all, seek a solution by negotiation, enquiry, mediation, conciliation, arbitration, judicial settlement, resort to regional agencies or arrangements, or other peaceful means of their own choice.
Depending on the extent of their obligations under international law, States may be compelled to participate in certain forms of dispute settlement – for example, States may accept the jurisdiction of the International Court of Justice (ICJ) under Article 36(2) of the Statute of the ICJ, or incorporate a compromissory clause within a treaty that grants the ICJ jurisdiction in relation to disputes emerging under that agreement. However, absent such a rule of international law, a corollary of the principle of the sovereign equality of States is the principle of free choice of means, which means that States are free to decide for themselves which peaceful means and methods to use to settle their disputes or, put differently, States cannot be compelled to participate in a dispute settlement process unless they have given their consent.Footnote 16 In fact, the methods listed in Article 33(1) are not exhaustive, with this provision explaining that States can settle their disputes through ‘other peaceful means of their own choice’. For instance, States often use good offices to help resolve their disputes and, while this method is not mentioned in Article 33(1), it is referred to in the 1899 Hague Convention and the UN General Assembly’s (UNGA) Manila Declaration. States can also combine methods and create bespoke processes aimed at settling their disputes.Footnote 17 Under Article 37 of the UN Charter, if States are unable to settle a dispute by peaceful means, they must refer it to the UN Security Council (UNSC).
The obligation of peaceful dispute settlement has undoubtedly acquired the status of customary international law.Footnote 18 This status is supported by the near-universal membership of the UN Charter,Footnote 19 together with the fact that the obligation is embedded in a number of successive treaties.Footnote 20 The customary law status of the obligation is also confirmed by its inclusion in multiple resolutions of the UNSCFootnote 21 and declarations of the UNGA.Footnote 22 Importantly, the obligation of peaceful dispute settlement is contained in the 1970 Friendly Relations Declaration (FRD),Footnote 23 whose adoption by the UNGA without the need for a vote ‘may be understood as an acceptance of the validity of the rule or set of rules declared by the resolution by themselves’.Footnote 24 The FRD explains:
Every State shall settle its international disputes with other States by peaceful means in such a manner that international peace and justice are not endangered.
States shall accordingly seek early and just settlement of their international disputes by negotiation, inquiry, mediation, conciliation, arbitration, judicial settlement, resort to regional agencies or arrangements or other peaceful means of their choice. In seeking such a settlement the parties shall agree upon such peaceful means as may be appropriate to the circumstances and nature of the dispute.
Additionally, the UNGA adopted the Manila Declaration on the Peaceful Settlement of International Disputes in 1982, which was also adopted without the need for a vote.Footnote 25 This Declaration explains that
States shall seek in good faith and in a spirit of cooperation an early and equitable settlement of their international disputes …. In seeking such a settlement, the parties shall agree on such peaceful means as may be appropriate to the circumstances and the nature.
The international society has developed a sophisticated system of peaceful dispute settlement that comprises a dense patchwork of principles, rules, procedures, and institutions. The obligation of peaceful dispute settlement is a critically important feature of this system and, while it represents an ontologically distinct obligation under international law, it sits alongside other international legal rules that work together to ensure the maintenance of international peace and security.Footnote 26 Take, for example, the principles of non-intervention and non-use of force. The principle of non-intervention is ‘part and parcel of customary international law’ and prohibits States from coercively intervening in the domaine réservé of other States.Footnote 27 The principle of non-use of force prohibits States from engaging in acts of violence (and threats thereof) against other States and is embedded in a number of treaties as well as customary law.Footnote 28 Most notably, this principle is enshrined in Article 2(4) of the UN Charter, which reads:
All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.
Action amounting to a breach of the non-intervention and non-use of force principles may also constitute a breach of the obligation of peaceful dispute settlement on the basis that it involves the use of a non-peaceful means to resolve a dispute.Footnote 29 Importantly, however, the obligation of peaceful dispute settlement goes beyond prohibiting the use of non-peaceful means to resolve disputes and imposes an ‘affirmative duty’ on States to work together to find a peaceful means to settle their disputes.Footnote 30 This was recognised by the ICJ in the Nicaragua judgment when it held that the obligation to settle disputes peacefully is ‘complementary to the principles of a prohibitive nature’ found in international law such as the principles of non-intervention and non-use of force.Footnote 31 Yet, to determine the content of the obligation of peaceful dispute settlement, it is first necessary to investigate the conditions for its engagement. The next section turns to this issue.
1.3 Conditions for the Engagement of the Obligation of Peaceful Dispute Settlement
Establishing the conditions for the engagement of the obligation of peaceful dispute settlement entails answering three questions: (1) when does a dispute come into existence; (2) whether a dispute should present certain features to engage the obligation; and (3) what parties are subject to the obligation. Each issue is addressed in turn.
1.3.1 Existence of a Dispute
The existence of a dispute is the trigger of the obligation of peaceful dispute settlement.Footnote 32 Yet, there is considerable uncertainty regarding what situations qualify as a ‘dispute’, or even whether a unitary definition of ‘dispute’ exists in international law.Footnote 33 The term ‘dispute’ appears in several international conventions and is not used consistently.Footnote 34 Indeed, the notion of a dispute may have different implications depending on the purpose for which it is sought. The existence of a dispute is often the precondition for the exercise of jurisdiction by an international court or tribunal.Footnote 35 In this regard, most international courts and tribunals define disputes by reference to the Mavrommatis case, where the Permanent Court of International Justice (PCIJ) held that a dispute is ‘a disagreement on a point of law or fact, a conflict of legal views or of interests between two persons’.Footnote 36 It is questionable, however, whether this definition is satisfactory for the purpose of the obligation of peaceful settlement. First, international courts and tribunals are only ever concerned with ‘justiciable’ disputes, that is, disputes that ‘can be resolved by the application of rules of law by judicial (including arbitral) processes’.Footnote 37 Second, the Mavrommatis definition is formulated in such general terms that, at best, it provides very little guidance when it comes to identifying specific disputes and, at worst, it may be overinclusive.Footnote 38 Indeed, the ICJ, followed by other international courts and tribunals,Footnote 39 has added several qualifications to this definition, stating in particular that a dispute comes into existence when ‘the claim of one party is positively opposed by the other’,Footnote 40 and that this ‘opposition’ may ‘be inferred from the failure of a State to respond to a claim in circumstances where a response is called for’.Footnote 41
These qualifications are also helpful when establishing the existence of a dispute for the purpose of the obligation of peaceful settlement, in that they shift the focus from the ‘conflict of views or interests’ (in itself a subjective condition) to the externalisation of such conflict through the conduct of the parties (which is capable of objective determinationFootnote 42). This notion was best captured by Judge Morelli, who described the essence of a dispute as the ‘contrast between the respective attitudes of the parties in relation to a certain conflict of interests’.Footnote 43 To be more precise, Judge Morelli found that the existence of a dispute requires ‘a manifestation of the will, at least of one of the parties, consisting in the making of a claim or of a protest’.Footnote 44 The opposition to this manifestation of will may take the form of a (counter-)claim, in which one party rejects the claim(s) put forward by the other party. It may also be inferred from the conduct of one party, so long as it is incompatible with the claim(s) advanced by the other parties.Footnote 45
The claims of (at least one of) the parties are thus an essential element for the establishment of a dispute. Through their claims, the parties control not only the moment at which the conflict of views or interests materialises but also, depending on the type of arguments used to support them, the content and nature of the dispute.Footnote 46 For instance, the use of ‘moral’ or ‘historical’ arguments will maintain the dispute in the ‘political’ sphere, but the move towards ‘legal’ arguments by one of the parties will give rise to a ‘legal’ dispute. Whether this has an impact on the engagement of the obligation of peaceful settlement will be explored in Section 1.3.2. For now, it is worth noting that, if the claims of the parties determine the existence and content of a dispute, some communications between the parties seem to be a necessary precondition for the emergence of a dispute (and thus for the engagement of the obligation of peaceful settlement). As Schreuer puts it, ‘the matter must have been taken up with the other party, which must have opposed the claimant’s position if only indirectly’.Footnote 47 At the same time, this should not imply that a particular ‘threshold’ of communications must be reached before it can be said that a dispute has arisen. In this regard, the ICJ has sparked debate – and criticismFootnote 48 – with its decision in the Nuclear Arms and Disarmament cases, where it held that ‘a dispute exists when it is demonstrated, on the basis of the evidence, that the respondent was aware, or could not have been unaware, that its views were “positively opposed” by the applicant’ and that this must have occurred ‘at the time of their submission’ to the Court.Footnote 49 Yet, the emphasis the ICJ placed on the time of the submission suggests that the Court was preoccupied not so much with disputes tout court but with specific disputes subject to the jurisdiction of the Court.Footnote 50
The existence of a dispute as the trigger of the obligation of peaceful dispute settlement is a different issue compared to its suitability for adjudication by international courts and tribunals. The externalisation of a conflict of views or interests through the claims of one of the parties is sufficient to give rise to a dispute so long as these claims are incompatible with the claims or conduct of the other party.Footnote 51 Such claims can be made in several ways and require no formalities;Footnote 52 they can be raised through diplomatic exchanges but also through more informal means of communication between the parties.Footnote 53 A parallel can be drawn between the dynamics by which a dispute arises and the means by which a State can invoke the responsibility of another State for internationally wrongful acts. As the International Law Commission (ILC) has highlighted, the invocation of responsibility may occur through ‘diplomatic contacts … [which] involve specific claims by the State concerned, such as for compensation for a breach affecting it, or specific action such as the filing of an application before a competent international tribunal, or even the taking of countermeasures’.Footnote 54 Indeed, with the exception of the Nuclear Arms and Disarmament cases, international courts and tribunals have rarely, if ever, declined jurisdiction on the basis of the non-existence of a dispute, particularly if, ‘at the latest by the date when the Court decides on its jurisdiction’, the applicant would be entitled ‘to bring fresh proceedings’.Footnote 55
This is not to say that communications between the parties are not necessary for the settlement of a dispute. However, the extent to which the parties should engage in exchanges to fulfil the obligation of peaceful settlement is a separate issue, which pertains to the content of the obligation.Footnote 56 As far as the engagement of the obligation is concerned, once a dispute has come into existence, what remains to be asked is whether such a dispute should possess certain features to give rise to the obligation of peaceful settlement. The next subsection turns to this.
1.3.2 Character of the Dispute
As Merrills stated, ‘international disputes can be about almost anything’.Footnote 57 It may thus be asked whether all disputes trigger the obligation of peaceful settlement or whether the latter should be reserved only for certain classes of disputes. In this regard, it is important to recall the function the obligation of peaceful dispute settlement serves under the UN Charter and general international law. The premise is that disputes, if left unchecked, may cause friction in international relations and have the potential to escalate, thereby threatening international peace and security. As will be further explored below, the obligation of peaceful dispute settlement aims at reducing this risk by compelling the States to ‘manage’ their disputes and ensure these do not spiral out of control. Although the potential for escalation may be very different in practice, in principle all disputes present such a risk. Thus, Article 33 of the UN Charter mandates member States to seek a solution to a dispute ‘the continuance of which is likely to endanger the maintenance of international peace and security’. To be sure, other provisions in the UN Charter appear to add qualifications to the obligation. In particular, Article 2(3) restricts the obligation of peaceful settlement to ‘international disputes’. This provision must be read in conjunction with Article 2(7), which provides that member States are not required to submit to settlement ‘matters which are essentially within the[ir] domestic jurisdiction’. The obligation of peaceful dispute settlement is thereby limited to disputes that are ‘international’ in the sense of not being ‘purely internal’.Footnote 58 Yet, the scope of this limitation is not static; the very notion of essential domestic jurisdiction excluding the international character of a dispute has shrunk over time.Footnote 59 Domestic jurisdiction can only be defined in the negative as the area in which a State has not taken up international obligations.Footnote 60 This, coupled with the growing number of inward-looking norms (i.e. ‘norms that aim to regulate State conduct within the domestic jurisdiction’Footnote 61), means that several disputes once regarded as purely internal are now unquestionably international in character – with human rights disputes being the most visible example.
The existence of a dispute concerning matters that are regulated by international law is therefore necessary for the engagement of the obligation of peaceful dispute settlement. At the same time, this does not imply that the arguments of the parties must be based on international law, as suggested by Peters.Footnote 62 As discussed above, the claims of the parties are key to the characterisation of the dispute. If the parties use international law in support of their claims, the dispute will be unquestionably ‘international’ in character, thereby giving rise to the obligation of peaceful settlement. Similarly, the choice of using legal arguments – and even more so the choice of some legal arguments to the exclusion of othersFootnote 63 – will have implications for the means available for its settlement. However, the risk of placing too much emphasis on the arguments used by the parties is to limit the obligation to legal disputes, ignoring those in which the parties rely on extra-legal (e.g. political, moral, historical) arguments.Footnote 64 Disputes of the latter kind, if left unchecked, may very well spiral out of control and threaten international peace and security as much as any legal dispute.Footnote 65 Thus, limiting the ambit of the obligation of peaceful dispute settlement to specific classes of disputes seems unwarranted. If a dispute pertains to matters that are regulated by international law, the obligation of peaceful dispute settlement is triggered for the simple fact that the issue is one of international concern. Further qualifications may contribute to shaping the content of the obligation of peaceful dispute settlement by determining the steps that should be taken to fulfil it. For instance, Article 36 of the UN Charter provides that ‘legal disputes’ should as a general rule be referred to the ICJ, while Article 52 suggests that ‘local disputes’ may involve settlement through regional agencies or agreements. However, the content of the obligation should not be conflated with the conditions for its engagement. If the ‘international’ character of a dispute is not only a necessary but also a sufficient condition for the engagement of the obligation, the question is whether international dispute settlement exclusively concerns disputes among States,Footnote 66 or whether the ever-growing phenomenon of ‘mixed’ disputes involving State and non-State actors is also affecting the scope of the obligation. The next subsection turns to this.
1.3.3 Subjects of the Obligation
The PCIJ’s definition of a dispute in the Mavrommatis case referred to ‘a disagreement … between two persons’.Footnote 67 This choice of words was almost certainly intended as a reference to ‘international legal persons’, which at the time equalled States.Footnote 68 This is reinforced by the fact that, under the system created by the 1899 Hague Convention, dispute settlement was essentially a matter of inter-State relations. Even disputes involving non-State actors acquired international relevance only to the extent that a State raised the issue against another State. Notably, the PCIJ held that ‘by taking up the case of one of its subjects and by resorting to diplomatic action or international judicial proceedings on his behalf, a State is in reality asserting its own rights’.Footnote 69 In the following decades, States, acting as ‘gatekeepers’ of the international legal system,Footnote 70 have recognised limited forms of international legal personality over non-State actors, such as international organisations, individuals, and corporations.Footnote 71 In several instances, these actors have been granted direct access to international judicial bodies for the settlement of disputes that affect them, particularly in human rights and investment matters.Footnote 72 The ‘proliferation’Footnote 73 of international courts and tribunals competent to settle disputes involving both States and non-State actors has led some to question whether ‘international dispute settlement properly so-called’ should be confined to cases involving States.Footnote 74 This question has an obvious impact on the extent to which the obligation of peaceful dispute settlement applies to State and non-State actors alike.
The starting point is that the obligation of peaceful dispute settlement is first and foremost an obligation binding on States. While instruments such as the 1970 FRD compel States to settle ‘international disputes with other States’, other instruments do not contain such limitations. Notably, Article 2(3) of the UN Charter sets out an obligation of the member States to settle ‘their international disputes’, and Article 33 of the UN Charter refers to ‘any dispute, the continuance of which is likely to endanger the maintenance of international peace and security’. It is reasonable to assume that, if a dispute may endanger international peace and security, the States remain under an obligation to seek a solution regardless of whether the other party is a State or non-State entity.Footnote 75 Whether non-State entities, in turn, bear an obligation in this sense is a more difficult question.
It is well known that the UN and other international organisations may have a significant role to play as settlers of international disputes.Footnote 76 Increasingly, however, international organisations may themselves be parties to international disputes concerning, for instance, the responsibility arising from their activities vis-à-vis member States, third States, and non-State parties (individuals, other organisations, etc.).Footnote 77 Considering that the obligation of peaceful dispute settlement exists as a matter of customary international law, international organisations are in principle bound by the same obligation with respect to the settlement of their disputes.Footnote 78 To be sure, access to the means of dispute settlement may be significantly more limited in cases involving international organisations.Footnote 79 Thus, what international organisations must do in order to fulfil their obligation may be different from what is required of States. At the same time, some of the steps explored further in Section 1.4 can be expected also from international organisations. This is a fast-evolving area of international law which has been recently added to the long-term programme of work for the ILC and therefore requires further scrutiny in the future.Footnote 80
Under customary international law, other non-State actors may be right-holders or duty-bearers in relation to the settlement of disputes.Footnote 81 Whether these obligations include the general obligation of peaceful dispute settlement depends on the circumstances of the specific entity. Some non-State actors, such as national liberation movements (particularly when exercising territorial control), may be bound by the general rules of international law that are not exclusively directed to the States.Footnote 82 Obligations pertaining to international dispute settlement would certainly fall within this category given the prominent role these actors play in the settlement of international disputes. The UNSC has frequently called on them to enter negotiations with their government opponents to achieve a settlement of their disputes.Footnote 83 These actors may have access not only to diplomatic means of dispute settlement but also to judicial means as demonstrated by the Abyei arbitration.Footnote 84 As to individuals in general, their international legal standing in the settlement of disputes is more limited compared to that of other international legal subjects. And yet, once individuals are granted direct access to international courts and tribunals (particularly if they are acting for the protection of a right of their own that is distinct from that of the StateFootnote 85), there are, in principle, no reasons to exclude them from the general rules of international law governing the settlement of international disputes to the extent applicable to them.Footnote 86 Once again, the key question is one not of engagement but of the content of the obligation of peaceful settlement.
1.4 Content and Effects of the Obligation of International Dispute Settlement
Having identified the conditions that trigger the application of the obligation of peaceful dispute settlement, the immediate question is what this obligation entails. To fully grasp the content of the obligation of peaceful dispute settlement, it is first necessary to identify the setting in which it operates, that is, to flesh out the character of the process of a peaceful dispute settlement (Subsection 1.4.1). This analysis will reveal that, given that the obligation operates in a dynamic context, its content is itself dynamic and varies depending on the circumstances of each case (Subsection 1.4.2). While the obligation has a normative content of its own and imposes specific conduct on the parties to a dispute, it will be shown that the obligation can also operate as an interstitial norm and influence the content of other obligations (Subsection 1.4.3).
1.4.1 Situating the Obligation in the Dynamic Process of International Dispute Settlement
As ‘historical facts’, disputes arise at a given moment, persist for a certain duration, and, if settled, come to an end.Footnote 87 It is therefore commonplace to think of the obligation of peaceful dispute settlement as operating in a linear fashion. However, this linear understanding of dispute settlement makes it extremely difficult to give any meaningful content to the obligation of peaceful dispute settlement.
The first obstacle is that the obligation of peaceful dispute settlement is one of conduct, not of result.Footnote 88 This is the case also when the obligation is formulated in seemingly strict terms such as those of Article 33 of the UN Charter (‘shall … seek a solution’). Because one party alone cannot settle a dispute without the agreement of the other party – lest the obligation mandates one of the parties to give up its claims – the obligation can only impose a duty to ‘undertake efforts towards that purpose’.Footnote 89 That the obligation cannot be one of result is also evidenced by the fact that the submission of a dispute to a means of dispute settlement is no guarantee that ‘settlement’ – in itself a vague conceptFootnote 90 – will be reached. This is evident in the case of diplomatic methods (negotiation, good offices, mediation, inquiry, and conciliation), where, in the absence of binding outcomes (unless the parties have made stipulations to this end),Footnote 91 settlement is completely reliant on extra-legal factors which may be outside the control of any individual party. Yet, even the submission to a judicial means of dispute settlement does not necessarily ensure that the disagreement at the heart of a dispute will be resolved.Footnote 92 In other words, regardless of the means chosen, the settlement of a dispute requires concerted and concordant action on behalf of all disputing parties – a ‘result’ that is beyond the exclusive control of a single party at any given moment.
Even when the obligation of peaceful dispute settlement is seen as one of conduct, it is not immediately evident what conduct it requires. As we saw above, it is a well-established principle that the parties to a dispute, unless they have agreed otherwise, are under no obligation to submit it to a specific means of dispute settlement. The absence of a specific course of action the parties must undertake to fulfil the obligation gives them a ‘wide margin of discretion’ and can even lead to an impasse.Footnote 93 Because States are not bound to submit to any specific means of dispute settlement, it may seem that they cannot be compelled to do anything concrete to settle their disputes despite being subject to an obligation to this end.
If States cannot be compelled to settle their disputes, it may be argued that, at the very least, they should be bound to refrain from engaging in acts that would aggravate the dispute.Footnote 94 However, the parties to a dispute may deem it necessary to resort to limited forms of escalation in order to persuade a recalcitrant counterparty to submit to a means of dispute settlement. It is generally accepted that unfriendly but lawful acts do not run into conflict with the obligation of peaceful dispute settlement.Footnote 95 These include measures of retorsion (such as the expulsion of diplomats) and countermeasures (which are breaches of international obligations whose wrongfulness is precluded by virtue of their function as a means to implement the international responsibility of wrongdoing States). The risk is that these exceptions may swallow the rule, given that States taking aggravating measures will almost always claim that they have valid reasons to do so.Footnote 96
A more meaningful effort to conceptualise the obligation of peaceful dispute settlement should therefore begin by acknowledging that disputes are not static phenomena; they arise, evolve, and mutate in response to the conduct of the parties. As seen above, the existence of a dispute can only be ascertained by contrasting the claims of a party with the action and/or claims of another party. The context continues to inform the required conduct of the parties as the dispute develops. Further claims or actions by either party may contribute to the evolution of the dispute by specifying its terms, or may create new disputes concerning the legality of the reaction or connected incidents. These steps cannot be seen in isolation; the legality of the conduct of the parties to a dispute is necessarily influenced by the context and must take into account their past and (possible) future interactions.
This is of particular significance when seeking to ascertain whether the continuance of a dispute is likely to endanger international peace and security under Article 33 of the UN Charter. A disagreement of a relatively minor character between two States with a history of friendly relations is unlikely to threaten international peace and security. In such a context, the parties to the dispute have significant leeway in deciding how to deal with it: they can set it aside temporarily to preserve their friendly relations in other fields; they can attempt to settle it via peaceful means; or they can take unfriendly measures in the form of retorsion or countermeasures that will be unlikely to endanger international peace and security. The same cannot be said when disputes arise between two States that are already experiencing hostile relations – in this environment, acts of escalation may spiral out of control. In fact, it may be argued that all unsettled disputes have the potential of escalating over time and threatening international peace and security. For this reason, Cassese reasoned that ‘the obligation of peaceful settlement might concern all disputes’.Footnote 97 The consequence is that the obligation of peaceful dispute settlement must be seen as a dynamic one, whose content varies according to the circumstances of the dispute.Footnote 98 In particular, as the next subsection shows, the greater the threat to international peace and security posed by a dispute, the more demanding the obligation becomes.
1.4.2 Dynamic Content of the Obligation
As seen above, the obligation of peaceful dispute settlement does not just proscribe the use of non-peaceful means to resolve disputes, but also imposes a positive duty upon the States to engage with each other and work together with a view to settling their disputes. That the obligation of peaceful dispute settlement requires ‘active efforts’Footnote 99 from the States is indicated by the language of Article 33(1) of the UN Charter, which explains that the UN members must ‘seek a solution’ to their disputes. In a similar vein, the FRD explains that ‘States shall accordingly seek early and just settlement of their international disputes’, and the Manila Declaration provides that ‘States shall seek in good faith and in a spirit of cooperation and early and just settlement of the international disputes’. All these authorities point to the fact that States cannot remain inert or inactive in the face of a dispute.Footnote 100 However, when it comes to identifying the concrete steps that States must take when faced with a dispute, the picture is more nuanced.
A number of commentators have interpreted the obligation of peaceful dispute settlement broadly. For them, this obligation does not just require the States to work together to identify a peaceful means that can be used to settle their disputes, but it imposes a more arduous duty to enter into negotiations and attempt to resolve the substance of the dispute itself.Footnote 101 In this context, the duty to negotiate requires, as a baseline minimum, the disputants to listen to the arguments of the opposing parties, reflect on their own positions in light of these arguments, and engage in meaningful dialogue in an attempt to resolve the dispute.Footnote 102
This interpretation of the obligation of peaceful dispute settlement is problematic. In the Bolivia v. Chile case, Bolivia maintained that Chile had failed to comply with its duty to negotiate an agreement that granted Bolivia access rights through Chile’s territory to the Pacific Ocean.Footnote 103 Reaffirming its previous jurisprudence,Footnote 104 the Court held that an obligation to negotiate can only arise where the parties have expressed an intention to be legally bound.Footnote 105 Bolivia argued that Chile’s intention to be bound by a duty to negotiate could be derived from the obligations to settle disputes peacefully as contained in Articles 2(3) and 33(1) of the UN Charter, but the Court rejected this interpretation when it held that ‘there is no indication … that the parties to a dispute are required to resort to a specific method of settlement, such as negotiation’.Footnote 106 Correctly in our view, the Court justified this conclusion on the basis that a duty to negotiate is at odds with the principle of free choice of a means of dispute settlement.Footnote 107
Despite this, there is a grain of truth in the argument that, without a minimum conduct baseline, the obligation to settle disputes peacefully would be devoid of any meaning.Footnote 108 While the States cannot be compelled to submit their disputes to a specific means of dispute settlement, the fact that they are required, in principle, to seek to settle their disputes by peaceful means and to do so in good faithFootnote 109 entails that they must, at the very least, engage in a meaningful exchange of views.Footnote 110 This is not the same as an obligation to negotiate the substance of the dispute; it concerns ‘the ways in which the dispute will be settled rather than … the merits of the dispute’.Footnote 111 The difference is most evident in the UN Convention on the Law of the Sea, where the obligation to exchange views is a precondition for access to the dispute settlement mechanism of the Convention.Footnote 112 As mentioned above, the very existence of a dispute requires a minimum baseline of communication that allows the parties to be aware of the nature and scope of their disagreement. An exchange of views is also necessary to give meaningful content to the obligation of peaceful dispute settlement, because in order to settle a dispute, the parties must at least assess whether dispute settlement mechanisms would be practically available.
As an obligation of conduct rather than result, where the States have co-operated in good faith and that, after all reasonable efforts have been exhausted, they are still unable to agree on a means for resolving their disputes, they do not have to consult ad infinitum.Footnote 113 The reason for this is because some disputes may be so entrenched and adversarial that it is practically impossible for the parties to agree on which means to use to resolve their disputes. In these circumstances, forcing the States to continue to discuss their disputes when it is clear that no agreement can be reached may be counterproductive and may actually exacerbate the dispute. Instead, the parties may be under an obligation to freeze the dispute and pause discussions until an environment emerges that is more conducive to a peaceful settlement of the dispute.Footnote 114 But given the dynamic nature of the obligation of dispute settlement, where there is a material change in circumstances surrounding the dispute – for example, the political climate improves because there is a change in government in one or all of the disputing States – the duty to seek a peaceful settlement is reactivated, and the disputants must resume their consultations and again work together in an attempt to find a means to settle their dispute.
On top of this, the obligation of peaceful dispute settlement has a role to play in preventing disputes from escalating and spiralling out of control. As seen above, limited forms of escalation are, in principle, permissible in the context of a dispute so long as they involve lawful measures (retorsion or countermeasures). At the same time, this freedom must be reconciled with the duty of the parties to a dispute to ‘refrain from any action which may aggravate the Situation so as to endanger the maintenance of international peace and security’.Footnote 115 The obligation of peaceful dispute settlement therefore includes a principle of non-aggravation that proscribes acts of escalation under certain circumstances.Footnote 116
The principle of non-aggravation inherent in the obligation of peaceful dispute settlement has an element of vagueness and indeterminacy.Footnote 117 However, it is in the interaction with other norms that the obligation most visibly exercises its normative pull. From this perspective, the obligation may colour the legality of the conduct of the parties by informing the content of other rules of international law, which in turn proscribe acts antagonistic to the settlement of disputes. In other words, the obligation of peaceful dispute settlement, alongside its status as a self-standing rule of international law, may also share some features with what Lowe describes as ‘interstitial norms’.Footnote 118
1.4.3 Interstitial Character of the Obligation
According to Lowe, interstitial norms are ‘normative concepts operating in the interstices between … primary norms’Footnote 119 and ‘direct the manner in which competing or conflicting norms that do have their own normativity should interact in practice’.Footnote 120 For the reasons mentioned above, the obligation of peaceful dispute settlement does have a normative charge of its own. However, this does not exhaust the normative pull of the obligation, which can also be appreciated by looking at its effects on other rules of international law. International law provides several norms which are inextricably linked to the process of dispute settlement and whose content is dependent on the circumstances of each case. Two examples are particularly emblematic in this regard.
The first concerns the regulation of countermeasures under the law of State responsibility. There is a clear connection between countermeasures and dispute settlement; as Simma noted, ‘recourse to counter-measures not involving the threat or use of force is in itself a peaceful means of settling a dispute arising from an internationally wrongful act’.Footnote 121 Yet, as Arangio-Ruiz pointed out, countermeasures are evidently ‘non-amicable’ when compared to other means of dispute settlement and thus have the potential of aggravating the dispute.Footnote 122 In his capacity as the ILC Special Rapporteur on State Responsibility, Arangio-Ruiz proposed to subject resorting to countermeasures to the ‘prior … exhaustion of all the amicable settlement procedures available under general international law, the Charter of the United Nations or any other dispute settlement instrument to which it [the reactor State] is a party’.Footnote 123 This proposal was deemed unrealistic by other ILC members and was ultimately rejected.Footnote 124 After several iterations, the ILC finally settled on the text of Article 52(1) of the Articles on State Responsibility, 2001 (ASR), which requires an injured State to ‘call on the responsible State … to fulfil its obligations’ and to ‘notify the responsible State of any decision to take countermeasures and offer to negotiate with that State’. Even the mere ‘offer’ to negotiate as a precondition to the taking of countermeasures gave rise to ‘lively debates’ within the ILC, evidencing a ‘central disagreement’ on the point.Footnote 125 Still, the fact remains that, in the normative conflict between the rules allowing the taking of countermeasures and those protecting the sovereignty of the target State, the obligation of peaceful dispute settlement exercises its normative pull. The injured State wishing to resort to countermeasures must first ensure that reasonable attempts to settle the dispute have been made. What is reasonable depends on the circumstances of the case and is tempered by the exception for ‘urgent’ countermeasures pursuant to Article 52(2) of the ASR.Footnote 126 Still, measures taken without any consideration for the settlement of the dispute will likely run counter to customary international law.
The continuing normative pull of the obligation of peaceful dispute settlement on the law of countermeasures is further demonstrated by Article 50(2)(a) of the ASR, according to which ‘a State taking countermeasures is not relieved from fulfilling its obligations … under any dispute settlement procedure applicable between it and the responsible State’ and, most importantly, by Article 52(3)(b) of the ASR, which provides that ‘countermeasures may not be taken, and if already taken must be suspended without undue delay if … the dispute is pending before a court or tribunal which has the authority to make decisions binding on the parties’. This is an important aspect of the connection between the legality of countermeasures and the dynamic nature of the obligation of peaceful dispute settlement. Where a means of dispute settlement has been selected, ‘for so long as the dispute settlement procedure is being implemented in good faith, unilateral action by way of countermeasures is not justified’;Footnote 127 any countermeasure would constitute in and of itself an aggravation of the dispute running counter to the obligation of dispute settlement. As the ILC commentary explains, this is because ‘once the parties submit their dispute to such a court or tribunal for resolution, the injured State may request it to order provisional measures to protect its rights’.Footnote 128 At the same time, the obligation of peaceful dispute settlement continues to expand or contract according to the evolving circumstances. Thus, the ASR go on to specify that this limitation on the taking of countermeasures ‘does not apply if the responsible State fails to implement the dispute settlement procedures in good faith’.Footnote 129 Once again, the obligation is flexible enough to allow a party to resort to unilateral measures when the conduct of the other party is thwarting the peaceful settlement of a dispute.Footnote 130
An even more striking example of the normative pull exercised by the obligation of peaceful dispute settlement is the notion that, under certain circumstances, resorting to a judicial means of dispute settlement may be antagonistic to the settlement of a dispute and should therefore be deemed unlawful. This idea is captured in the principles of ‘abuse of right’ and ‘abuse of process’, which, according to Kolb, consist of ‘the use of procedural instruments or rights by one or more parties for purposes that are alien to those for which the procedural rights are established, especially for a fraudulent, procrastinatory or frivolous purpose, for the purpose of causing harm or obtaining an illegitimate advantage, for the purpose of reducing or removing the effectiveness of some other available process or for purposes of pure propaganda’.Footnote 131
Dispute settlement bodies have been reluctant to find that an abuse of process has occurred for multiple reasons.Footnote 132 Chief among them is the fact that the threshold for an abuse of process is high and a party often has several reasons to institute judicial proceedings; this makes it difficult for the other party to prove that proceedings have been improperly used.Footnote 133 The ICJ has never recognised as well-founded a claim of this kind and, on several occasions, has stated that ‘it cannot concern itself with the political motivation which may lead a State at a particular time, or in particular circumstances, to choose judicial settlement’.Footnote 134 Despite this, there is little doubt that abuse of process is firmly rooted in the general principle of good faith and, as such, is part of international law.Footnote 135 States have continued to plead abuse of process before international courts and tribunals in recent years,Footnote 136 and the claim has encountered some success before investment tribunals.Footnote 137
The notion of abuse of process is another way in which the obligation of international dispute settlement acquires a concrete normative dimension. It is imbued with the idea that the context in which the actions of a party to a dispute take place ultimately determines their legality. As seen above, the dynamic nature of the obligation means that certain steps that would be permissible (or even desirable) under different circumstances become impermissible when a party to a dispute is no longer seeking in good faith to achieve the peaceful settlement of that dispute.
1.5 Conclusion
The obligation to settle disputes peacefully is a critical element of the international society’s dispute settlement system and is embedded in multiple treaties as well as customary law. To date, the academic literature has largely focused on the means and methods to settle disputes without inquiring into the content of the peaceful dispute settlement obligation itself other than to the extent to which it prohibits resorting to force. To fill this gap in the literature, this chapter has elaborated on the conditions that activate this obligation and on the substance of the obligation. In doing so, this chapter has demonstrated that the obligation of peaceful dispute settlement is a complex and multifaceted rule that exercises ‘an immense gravitational pull’ both on its own terms and on the rules that surround it.Footnote 138 At a minimum, it requires a degree of communication that allows the disputing parties to be aware of the nature and scope of their disagreement and to assess the viability of a potential means to settle it. Even when no agreement concerning the settlement of a dispute can be reached, the obligation of peaceful dispute settlement continues to guide the behaviour of the disputing parties, and as a dynamic norm, its content changes in line with the mutating circumstances.
This chapter has also demonstrated that the obligation of peaceful dispute settlement operates as an interstitial norm insofar as it informs the interpretation and application of other rules of international law linked with the process of dispute settlement. Understood in this way, the obligation of peaceful dispute settlement ensures that the conduct of the disputing parties, even when not bound by obligations concerning specific means of dispute settlement, remains within tolerable boundaries and does not stray too far from the goal of peaceful dispute settlement. Far from being a mere duplicate of the prohibition on the threat or use of force, the obligation of peaceful dispute settlement is rich in normative content and plays an essential role in preventing disputes from spiralling out of control and maintaining international peace and security more generally.
