Bargaining and Focal Points

To develop our argument on the role of international law in the peaceful resolution of territorial disputes, we draw on the rationalist bargaining literature on international cooperation (e.g., Blaydes Reference Blaydes2004; Fearon Reference Fearon1998; Koremenos, Lipson, and Snidal Reference Koremenos, Lipson and Snidal2001; Morrow Reference Morrow1994). Specifically, we focus on how leaders must solve distribution problems if they are to reach an agreement (e.g., Fearon Reference Fearon1998; Garrett and Weingast Reference Garrett, Weingast, Goldstein and Keohane1993; Keohane and Martin Reference Keohane and Martin1995; Koremenos, Lipson, and Snidal Reference Koremenos, Lipson and Snidal2001; Krasner Reference Krasner1991; Martin and Simmons Reference Martin and Simmons1998; Morrow Reference Morrow1994). Leaders have incentives to solve the problem and reach an agreement because, as other scholars have argued, allowing a dispute to continue can carry considerable political and military costs (Simmons Reference Simmons1998).Footnote ¹⁶

Distribution problems are central to territorial disputes for several reasons. First, any piece of contested territory can be divided an infinite number of ways. Second, leaders will have conflicting preferences over which of these possible solutions they would accept as the final settlement. In addition, because there is usually private information over the minimum amount of territory a leader is willing to accept, it is possible for states to misrepresent their bargaining positions. In light of these three common aspects, it is not surprising that disputes are often resolved over time through a series of offers and counteroffers as leaders try to avoid concessions while holding out for a better deal.

We argue that when legal principles are able to act as a focal point, they can help resolve the distribution problem and break the bargaining impasse by indicating how the disputed territory should be divided between the two states. This is true for at least two reasons. First, international law can help leaders identify which legal principles are relevant to the dispute. In doing so, international law provides a way to frame the problem by focusing on evidence and arguments that establish the legal merits of each state's claims to the territory in question. Once these legal principles have been identified, states can then begin to craft an agreement based on the merits of legal claims.

Second, as Schelling (Reference Schelling1960, 71) argues, focal points help leaders overcome distribution problems by providing them with a way for leaders to “coordinate their expectations.” The need for convergent expectations is critical because many failures to settle stem from the fact that bargaining “includes maneuver, indirect communication, jockeying for position, or speaking to be overheard, or [a confusion of] a multitude of participants and divergent interests” (74). If parties are to reach an agreement, Schelling posits, then they must identify a single point (or a narrow range of points) within the bargaining range that neither side expects the other to reject. Recognizing this strategic element of bargaining wherein one state attempts to predict what its adversary expects it to offer, as well as how this facilitates the convergence of expectations, is crucial to understanding how focal points can help parties overcome distribution problems.

On a related point, the ability of the focal point to narrow the range of acceptable outcomes also helps make negotiations more productive by limiting the ability of a state with weak legal claims to persist in misrepresenting the strength of its bargaining position in negotiations over a possible settlement. Leaders with weak legal claims are less able to make credible bluffs about the terms they are willing to accept if those terms are inconsistent with the distribution of territory called for by the focal point. For instance, if a focal point indicates the leader of state A should receive 75% of the territory, whereas the leader of state B is only entitled to 25%, then state B's leader knows that the leader of state A will not accept B's preferred settlement of an even split. Given this, leader B knows he or she must offer a division to A that is closer to 75% than to 50% to reach an agreement and avoid the costs of allowing the dispute to continue. The focal point also curtails the ability of the disputants to misrepresent what they think they are entitled to. That is, the leader of state B cannot credibly demand 90% of the disputed good when the focal point allocates only 25% to him or her. By narrowing the set of possible agreements, the focal point solves both the coordination and distribution problems by identifying which of the infinite number of potential settlements to start with. It also makes negotiations more efficient by deterring states from offering terms their adversaries would reject. Consequently, even though the existence of a distribution problem necessarily implies that parties have divergent preferences regarding the terms of the final settlement, having a focal point that identifies a particular solution can still influence leader behavior.

Focal Points and International Law

Several scholars, drawing on the insights of Schelling and others, have argued that international law is capable of providing a focal point to help leaders divide a valuable good (e.g., McAdams Reference McAdams2000; McAdams and Nadler Reference McAdams and Nadler2005, Reference McAdams and Nadler2008; Norman and Trachtman Reference Norman and Trachtman2005; Powell and Mitchell Reference Powell and Mitchell2007; Swaine Reference Swaine2002; Trachtman Reference Trachtman2008).Footnote ¹⁷ This notion rests on two assertions about the characteristics of international law.

First, international law and legal principles are common knowledge among states (McAdams and Nadler Reference McAdams and Nadler2005, Reference McAdams and Nadler2008), having been established through either formal channels (e.g., treaties, agreements, court rulings) or less formal means (e.g., customary international law, general principles, writings of legal scholars).Footnote ¹⁸ Consequently, they are a well-known source of third-party expression for leaders to reference when they disagree. Indeed, leaders will have strong incentives to invest the time and resources necessary to determine the strength of their state's legal claims.Footnote ¹⁹ For instance, if a leader suspects he or she has a legal advantage relative to his or her adversary, then he or she will want to investigate the relevant legal principles to support his or her claim. Leaders who are unsure about the strength of their state's claim will also have an incentive to determine their standing to prepare themselves against a possible legal challenge. Leaders that know they are at a legal disadvantage will, obviously, want to avoid drawing attention to specific legal principles that undercut their territorial aspirations. Their opponents, of course, will have every incentive to draw attention to the state's legal disadvantage, especially when they have strong legal claims. In sum, leaders will want to investigate and assess the merits of their legal-based claims to disputed territory, and, typically, at least one disputant per dispute will want to make the legal merits of rival claims to disputed territory known to third parties. The process of exchanging offers and counteroffers enables leaders to become more aware of how their adversary conceives of the legal issues and the possible merits of its legal claims. In doing so, information about the relative strength of the parties’ legal claims that was initially private becomes common knowledge as the disputants update their legal assessments based on new information.

Second, international law provides a common set of standards to assess the relative merits of competing claims. This feature is particularly important for resolving the distribution problems because it provides a means of identifying which of the many potential ways to divide the contested territory the leaders should choose. Some have questioned whether international law is capable of acting as an exogenous force on state behavior because critics claim it is often created by powerful states to further their own interests (Danilenko Reference Danilenko1993; De Visscher Reference De Visscher and Corbett1968; Goldsmith and Posner Reference Goldsmith and Posner2005). Although we recognize this concern, we second the claims of other scholars that it is possible for law to play a role independent of the states that created it (e.g., Abbott and Snidal Reference Abbott and Snidal1998; Byers Reference Byers1999, 17; Chayes and Chayes Reference Chayes and Chayes1995; Franck Reference Franck1990; Henkin Reference Henkin1979; Ikenberry Reference Ikenberry2000; Keohane and Martin Reference Keohane and Martin1995; Slaughter, Tulumello, and Wood Reference Slaughter, Tulumello and Wood1998). We have at least three reasons for arguing this.

First, many of the legal principles relevant to territorial disputes predate the territorial disputes we examine here. Therefore, although the great powers may have originally crafted specific legal principles to serve their interests in a particular dispute, it is possible that those same principles will work against the interests of the leaders of those same states in the future when new disputes arise. Second, international law is not simply a reflection of past or current great power preferences; the roster of great powers changes over time through war and other types of power shifts, and the number of new, smaller states has grown considerably in the post−World War II era. Third, the rulings from international courts and other legal bodies are seen by states as largely unbiased, or at least, not partial to a particular disputant before a decision is made.Footnote ²⁰

Conditions for a Focal Point

Having established international law's potential to provide a focal point for state leaders engaged in territorial disputes, we now turn to identifying the conditions under which we expect it to serve this function. In the existing literature, scholars have not specified when international law will be best equipped to provide a focal point. To address this lacuna, we posit that a focal point will most likely emerge if two conditions hold. First, the relevant legal principles must be clear and well-established. Second, and what is often overlooked, is that the relative strength of the disputant's legal claims must be asymmetric.Footnote ²¹ With regard to the first condition, without clarity, multiple interpretations of the law become possible, making it difficult for a single focal point (i.e., solution) to exist. With regard to the second condition, if neither state can make a superior legal case for their preferred solution, there is no reason to believe that international law will help them overcome the distribution problem. Thus, a compelling focal point is only likely to emerge if both conditions hold.Footnote ²²

As other scholars have noted (e.g., Chayes and Chayes Reference Chayes and Chayes1995; Fisher Reference Fisher1981), clarity in the relevant legal principles is often a necessary aspect for establishing a focal point. Although several legal principles may be relevant to a given dispute, there is no reason for us to expect them to be equally clear. Some laws may provide well-established standards for leaders to evaluate legal claims, whereas others might be more vague and therefore incapable of offering common standards for how states should interpret their claims. In addition, changes in the clarity of legal principles, although rare, are possible because a select number of legal issues relevant to territorial disputes have evolved over longer periods of time.Footnote ²³ This pattern of change is a product of the interaction between the compliance patterns of states, the terms of new international treaties, and the interpretation of legal principles by both legal bodies and experts.

In some cases, consistent and reinforcing patterns develop across these different sources of law, which promote future compliance. Other legal principles, however, may be subject to significant disagreement and different interpretations both by legal bodies and among states. As a result, the interpretations of some legal principles at any given time will vary in both their clarity and consistency. We expect those legal principles that are well developed and interpreted by states and courts in a consistent fashion to play a larger role in promoting dispute resolution. Conversely, legal principles that are subject to considerable debate and conflicting interpretations are unlikely to be helpful in resolving disputes peacefully.

The thalweg provides an example of a clear and well-established legal principle in the context of territorial disputes. The thalweg is the legal notion that a boundary line should lie in the center of the main navigable channel of the river. This general principle is both well known and clearly understood by leaders because customary state practice has used the thalweg as a guideline for establishing river boundaries for hundreds of years. By establishing a clear focal point, the thalweg helps leaders solve the distribution problem. Instead of debating over a large number of possible dividing lines across the entire width of the river, the parties can focus on identifying the main navigation channel and then situating the boundary line accordingly. In contrast, customary state practice is less clear and consistent in relying on the thalweg to determine sovereignty over islands in rivers. Consequently, although the thalweg is helpful in locating boundaries that correspond with rivers, it is less so with respect to settling disputes regarding sovereign rights to river islands.

Clear legal principles, however, although important, cannot resolve the distribution problem entirely. For a focal point to emerge that resolves the distribution problem, the legal principles must also favor one state. Only when the legal principles are clear and one state's legal claims are unquestionably stronger than the other's can international law help leaders find the bargaining solution that most accurately reflects the parties’ relative legal standing. If neither party has strong legal claims to the territory, then neither side will enjoy the bargaining leverage that comes with legal superiority. A mutual lack of bargaining leverage is consequential because it lessens the probability that the dispute will end in a settlement (and heightens the possibility of a stalemate) because neither leader will be able to muster a compelling reason for his or her opponent to make concessions. Consequently, without the backing of a focal point from international law, leaders will be less confident that they will be able to bring negotiations to a successful conclusion. They may instead be tempted to try to achieve their goals by issuing coercive threats or using force.Footnote ²⁴ A focal point, therefore, has a large role to play in guiding states down the path of peaceful dispute resolution. A focal point will also prompt states with weak legal claims to act in accordance with the legal-based distribution of territory because they lack the credibility to hold out for a better bargain.Footnote ²⁵

Hypotheses Regarding the Effect of the Focal Point

The preceding logic suggests two hypotheses for leader behavior in the first and second stages. For the first stage, the existence of a focal point should encourage leaders with a legal advantage to press for negotiations. There are at least two reasons for them to choose this option over either revising the status quo by force or leaving it unchallenged. First and foremost, because the terms of settlement suggested by international law align with their preferences for how their respective disputes should be resolved, they will be bargaining from a position of strength. Because a strong legal claim on their part necessarily implies that their opponents have weak legal positions, they should enter negotiations confident that they will be able to secure favorable settlements, via either a bilateral treaty or a formal legal ruling. As a result, once negotiations begin, they will be motivated to push their opponents to either accept agreements that reflect the legal superiority of their claims or consent to a formal process of legal dispute resolution. By a similar logic, they will also resist making significant territorial concessions to their adversaries.

The second reason legally advantaged leaders should prefer negotiations to revising the status quo through violence has to do with the clear legal principle against acquiring title to territory by force (e.g., Jennings Reference Jennings1963, 53–67; Korman Reference Korman1996; Oppenheim Reference Oppenheim1955, 570–75; Zacher Reference Zacher2001; but see Hensel, Allison, and Khanani Reference Hensel, Allison and Khanani2009). Since the end of World War II, a cornerstone of international law has been the illegality of changing borders through force. Although international boundaries routinely changed due to war in centuries past, resorting to military means in the post−World War II era would likely be an unproductive move for a challenger state with an otherwise strong legal claim to disputed territory. Not only might his or her aggression be countered by other states with sanctions or even direct military action, but it would also likely undermine the bargaining leverage he or she would have enjoyed had he or she pursued a more peaceful course of action and relied on his or her strong legal claims to the disputed territory in negotiations.Footnote ²⁶ The preceding logic implies the following hypothesis:

The existence of a focal point will also inform the behavior of both leaders in the second stage, where they must decide (collectively) to either end the dispute through some type of agreement or allow the dispute to continue. To understand why both leaders will have reason to accept a settlement that is grounded in international law, it is instructive to examine the strategic choices of each leader. For the leader of the state with the legal advantage, settling the dispute is the best option. As we argued previously, any settlements that materialize will likely favor leaders in this position. In light of this, they should have a strong preference to end the disputes rather than let them continue.

The asymmetric distribution of a legal advantage (and the associated focal point) will also affect the leader of the state with a weaker claim to the territory. If a focal point exists that favors the adversary, then the disadvantaged leader will be unable to marshal a compelling legal counter to the terms of settlement implied by international law because his or her claim to the disputed territory is, by definition, weak. He or she will also have a difficult time misrepresenting his or her reservation level regarding the distribution of territory. Although the leader of the weaker state could rebuff the stronger state's claims with military action, doing so is unlikely to further the weaker state's territorial goals. As we argued previously, in addition to the standard costs of conflict, using force could prompt other states to check such aggression with military retaliation or strong economic sanctions, making this a costly choice for the leader of the weaker state.

Moreover, the disadvantaged leader may also have incentives to accept the focal point, even if the associated terms of settlement will not favor him or her. As Fearon (Reference Fearon1998) points out, the military costs of continued disagreement between states can be substantial. Even if the states do not have a history of military confrontations, discordant relations stemming from an ongoing dispute can entail several other types of costs (e.g., political, economic) that the leader may want to avoid (Simmons Reference Simmons1998).Footnote ²⁷ Settling the dispute creates the possibility of a peaceful future and the associated benefits that come with it. Making peace with an adversary can free up resources that would otherwise be tied up in the dispute, allowing the leader to redistribute them to other domestic sectors (e.g., health care, education). Ending a dispute can also lead to a more collaborative and mutually beneficial relationship with the former adversary.Footnote ²⁸ In short, there are multiple reasons why a disadvantaged leader would choose to abide by the terms suggested by the focal point. The previous logic suggests the following hypothesis:

Domestic Cover

The preceding logic suggests that when international law can serve as a focal point, it can contribute to the peaceful settlement of territorial disputes through either bilateral negotiations or the formal process of dispute resolution (i.e., international adjudication or arbitration). We recognize, however, that a focal point cannot by itself predict which settlement venue disputants will choose for arbitration.Footnote ²⁹ In this section, we posit that the decision to pursue formal legal dispute resolution compared to bilateral settlements can be explained by identifying which leaders face higher political costs for making territorial concessions. Because territorial disputes are typically salient for the domestic public, leaders that are more accountable at home must consider the response of domestic actors before they agree to make concessions. Given this, we argue that leaders who require more domestic cover will be more likely to pursue legal dispute resolution. More specifically, we hypothesize that legally disadvantaged leaders of democracies will more often prefer a formal process of legal dispute resolution, whereas their autocratic counterparts will be more likely to accept a settlement brokered in bilateral negotiations.Footnote ³⁰

We believe that democratic leaders with weak legal claims require greater domestic cover because of two domestic political institutions that exist in modern democracies: a viable opposition and an electoral check. The combination of these two factors encourages the executive to distance him- or herself from politically unpopular decisions. Failing to do so will leave him or her open to accusations of policy incompetence that opposition elites will have every incentive to make as part of their effort to weaken the executive's hold on power. Such policy missteps will also trigger a negative reaction from domestic audiences, who prefer leaders who demonstrate political acumen, thereby decreasing the probability of reelection for the incumbent. This potential for domestic punishment is especially high for concessions made in the context of territorial disputes because nationalism is often linked to maintaining state borders, making leaders who agree to concessions vulnerable to charges of sacrificing national interests.

In light of this heightened likelihood of punishment, we expect that a democratic leader facing probable concessions as part of a territorial settlement will attempt to disassociate him- or herself from the terms of settlement as much as possible to insulate against any domestic political fallout.Footnote ³¹ As other scholars have argued (Allee and Huth Reference Allee and Huth2006; Simmons Reference Simmons and Diehl1999), pursuing a settlement through a formal process of legal dispute resolution is capable of providing a leader with useful political cover for at least three reasons that stem from the nature of the legal institutions involved in the settlement.

First, as many scholars have argued (e.g., Eyffinger Reference Eyffinger1996; Franck Reference Franck1990, Reference Franck1995; Voeten Reference Voeten2008), international legal bodies that would undertake the dispute resolution process are generally able to serve as unbiased third parties.Footnote ³² Second, within these legal bodies, it is customary to place a primacy on the importance of following formal procedures and giving both parties an equal chance to state their case. Third, and perhaps most importantly from the executive's perspective, the fact that both parties must agree in advance to the arbitrator's or court's terms of settlement helps to absolve the legally disadvantaged leader of any direct responsibility for the final outcome. This advantage is apparent when one considers the more direct and obvious role the executive would play if the settlement emerged from bilateral negotiations, where the leader would have had more control over the terms of the agreement.

Taken together, these institutional characteristics imply that domestic opponents of the executive will have a difficult time questioning the agreement on grounds of fairness or neutrality, or attributing the settlement as a failure on the part of the leader.Footnote ³³ This logic suggests the following hypothesis:

Control Variables

In addition to the variables of theoretical interest, we also control for several factors that may also influence leader behavior at the various stages. First, we control for whether both parties to the dispute are democracies. We expect joint democracy to exert a pacifying effect on states in the first stage, and encourage leaders to settle in the second. (e.g., Dixon Reference Dixon1994; Mitchell Reference Mitchell2002; Raymond Reference Raymond1994; Russett and Oneal Reference Russett and Oneal2001). Second, we control for the challenger's military capabilities relative to the target. We include this variable because we expect that, all else equal, stronger states will be more likely to take action in the first stage, be it thorough opening negotiations (and seeking to secure concessions in the shadow of power) or initiating a militarized dispute. In the second and third stages, because we are interested in behavior at the dispute level, we measure the military imbalance between the states (i.e., how far they are from parity). We expect that disputes characterized by an imbalance of forces are more likely to reach an agreement (on terms favoring the stronger party) and less likely to go to arbitration as the stronger party should prefer bilateral talks as the venue for reaching a settlement.

We also include a variable that captures whether the disputants have an alliance. We expect that, when interacting with an ally, the leader of a challenger state is more likely to pursue talks in the first round and will avoid using force. Likewise, in the second stage, we expect that allied states are more likely to resolve the dispute. We also control for the presence of coethnics. In the first stage, if the challenger state has ethnic ties to the population living in the contested territory, then we expect that the leader will challenge the status quo by either opening talks or threatening force. In the second and third stages, if both states lack ethnic ties to the disputed territory, then they will be more likely to reach a resolution and to do so through direct, bilateral negotiations.Footnote ³⁴ We also controlled for a history of stalemates between the disputants. When a dispute is marked by a lack of progress, challengers are less likely to pursue negotiations in the first stage. In the event that negotiations materialize and both disputants proceed to the second stage, they are unlikely to reach a final settlement. We also expect that disputes comprised of enduring rivals are more likely to have challengers use force in the first stage, fail to reach agreement in the second and opt for a process of international legal dispute resolution in the third. In the third equation, we also include a variable to highlight disputes in which the merits of each state's legal claims are either uncertain or highly complex. We expect this legal uncertainty to encourage states to favor either arbitration or adjudication over direct negotiations to reach a final agreement. Finally, to account for the possibility of duration dependence, we control for the effects of time by including a cubic polynomial of time (Beck, Katz, and Tucker Reference Beck, Katz and Tucker1998).

Measurement

Given both the novelty and importance of the international law variable, it is worth discussing the process we used to construct it in more detail. First, once the disputes were identified using the process described previously, we needed to assess the strength of each state's legal claims. To do so, we first searched systematically for expert legal assessments from scholars, rulings from international legal bodies, and government documents and archival materials for every territorial dispute.Footnote ⁴⁰ Next, we identified multiple expert sources for each territorial dispute and coded the legal judgments presented in the sources for each legal principle raised by the expert source.

We followed several guidelines when determining what constituted the superior legal claims of the state in question. First, we generally did not use public documents or statements by governments that were parties to a dispute to determine the merits of legal claims.Footnote ⁴¹ These public sources were often useful for understanding the legal claims put forward by states, but we did not use them for assessing the merits of those legal claims. However, when we were able to identify internal government sources that contained legal analyses and conclusions, we included them to determine the majority views among the expert sources.Footnote ⁴²

Second, we had to be aware of the potential for bias in legal assessments by scholars who are citizens of one of the countries in the dispute. When these scholars gave uniformly supportive analyses of their country's legal claims and uniformly negative assessments of the adversary country, we considered that source to be too biased to use in assessing the merits of legal claims. We often used this type of source, however, to identify what legal issues are relevant to the dispute and what kinds of legal arguments the country advanced in the dispute. If a national source is critical in some respects of its own state's legal claims, then we regarded that source as sufficiently balanced to include it when drawing conclusions about the majority position as represented in the expert sources.

To ensure intercoder reliability across the entire data set, a sample of 20 territorial disputes was initially examined independently by two coders who then exchanged their codings and discussed any differences and problems that arose in order to increase consistent coding of the cases. After this preliminary round of codings, we updated and clarified the coding rules and definitions. We then randomly assigned the population of territorial disputes to three different coders, while we randomly coded 80 of the cases that the three other coders were working on. Intercoder reliability on these 80 double-coded cases was quite high. The independent coding decisions were identical 84% of the time (67 cases).

Once we collected the necessary information, we aggregated the legal principles to establish state-level legal claims for both disputants. We considered a country's legal claim to be superior relative to its adversary if at least a majority of the following conditions was metFootnote ⁴³: (1) a history of customary state practice supported its legal claim and opposed the adversary's claim; (2) existing legal principles, as deemed by previous court rulings, backed the validity of the state's claim and found the adversary's claim lacking; and (3) the historical evidence and facts of the case clearly and consistently supported the state's claim when compared to the claim of its adversary. Importantly, not all criteria are relevant to every case. For example, in disputes where customary state practice is the key source of law backing legal principles (e.g., river boundaries and the thalweg principle), then past and recent international court rulings are less relevant. In contrast, when a state's legal claims failed to meet a majority of the preceding criteria, we coded the state as having weak legal claims.Footnote ⁴⁴

We operationalized this variable using a 3-point scale for each state, where 3 represented strong legal claims, 2 mixed legal claims, and 1 weak legal claim. If a state received a 3 on all legal issues relevant to the dispute, this state's position is either (1) strongly supported by existing legal principles according to the legal sources and experts or (2) a majority of the state's legal claims are judged to be strongly backed, whereas any remaining legal claims are judged as no worse than mixed. In short, a coding of strong legal claims requires that expert sources regarded at least a majority of the state's legal claims very favorably and saw none of its claims as weak.

For example, in the dispute between Ecuador and Peru over the Maranon border region, two legal principles are relevant to the dispute—pacta sunt servanda and rebus sic standibus.Footnote ⁴⁵ Several expert sources all rated Peruvian claims as strong except one source, which assessed the merits of Peru's claims on grounds of pacta sunta servanda as mixed (e.g., Barreto Reference Barreto1995). Ecuador sought to challenge the border established by the treaty of 1942 on the grounds that they were forced to sign it under duress. Moreover, new evidence from aerial photography in 1946 during demarcation indicated that the location of the border as presented in the Rio Protocol of 1942 was in error. As a result, Ecuador argued that the Rio Protocol was null and void. Legal sources, however, do not support this claim for two reasons. First, even after invoking the aerial photography evidence in 1946, Ecuador nevertheless recognized the validity of the Rio Protocol in official communications with both Peru and the United Nations. Second, scholars point out that the Ecuadorian Congress ratified the treaty after Peruvian troops left, which indicates that Ecuador accepted it willingly. Given this, rebus sic standibus does not apply, and Ecuador is bound by the principle of pacta sunt servanda (e.g., Barreto Reference Barreto1995; Puyo Reference Puyo1995).

The dispute between Afghanistan and the Soviet Union provides another example of clear legal principles giving one side a decisive advantage. In this case, the challenger, Afghanistan, had a stronger claim to the disputed territories in the Oxus River, based on the fact that Afghan claims to the location of the land border were based on previously agreed-on terms in the Treaty of Friendship signed by both states in 1921. Thus, the Afghans emphasized that their territorial claims were consistent with prior treaty obligations, whereas the Soviet's were not. In addition, Afghanistan pushed for the location of river boundaries based on the long-established customary principal of the thalweg. These legal advantages served Afghanistan well in negotiations; as our theory would predict, the final terms of the settlement in 1946 favored Afghanistan (Biger Reference Biger1995; Brownlie Reference Brownlie1979; Sharma Reference Sharma1997).

A state has mixed legal claims if, on balance, the expert sources determined that a state's legal claims to the contested territory are strong in some areas and either ambiguous or weak in others. Ambiguous claims are those in which the expert sources deem the relevant evidence to be either incomplete or contradictory, making the state's legal claims subject to qualification and reservations. Furthermore, the expert sources must agree that any strong legal merits of the state's claim do not compensate for the legal principles associated with the weaker legal claims. In the event that a majority of sources agree that a single legal principle outweighs the others, then the coding of the case rests on that legal principle.

Finally, a state received a coding of one if on the majority of the relevant legal issues, the legal sources believed that the state's position was either weak or was based on legal merits that were no better than “uncertain.” Put differently, a weak coding implies that legal experts do not judge a state's claims strong on any relevant legal principles. Returning to the Ecuador-Peruvian dispute, all expert sources agreed that Ecuador's legal claims were weak with respect to the principles of pacta sunt servanda and rebus sic standibus.

To illustrate the coding process more fully, it is useful to consider another example where states’ legal claims were either mixed or weak. Between 1934 and 1974, Britain/the United Arab Emirates (UAE) and Saudi Arabia were involved in a territorial dispute over claims to and around the Buraimi Oasis and other bordering territories along what has become the Qatari coastline. The relevant legal principles and issues in the dispute include (1) effective control, (2) the validity of the Blue Line found in the 1913 Anglo-Ottoman Convention and the 1914 Treaty, and (3) territorium nullius.Footnote ⁴⁶

First, legal scholars are divided on whether Saudi Arabia demonstrated continuous and effective control over the Buraimi Oasis and the tribes living in this area. Specifically, from 1800 to 1869, Albaharna (Reference Albaharna1975) argues that Saudi Arabia exhibited effective control over the disputed area. After 1869, however, the legal scholars note that the Saudis’ control was less certain than it had previously been. For instance, Albaharna claims that from 1869 to 1952, Saudi Arabia did not conform to the standards of “peaceful and continuous control,” which is necessary to demonstrate effective control. In addition, Wilkinson (Reference Wilkinson1991, 265) argues that Saudi Arabia's application of shari'a law in collecting zakat (taxes) was inconsistent until 1955, when it realized that it needed to conform to effective control to support its legal claim over the disputed territory. With respect to the other issues, scholars agree that Saudi Arabia was not bound by the Blue Line because Saudi Arabia was not party to the original convention between Great Britain and the Ottoman Empire, and the preceding treaties were never formally ratified. In addition, Great Britain did not consistently rely on the boundaries of Blue Line in its dealing with other states until the 1930s, when oil became an issue. As a result, this area was terra nullius, leaving Saudi Arabia free to extend its control. Nevertheless, because Saudi Arabia failed to fully comply with the requirements of effective control, we coded their legal claims as mixed.

However, the scholars were unanimous in their assessment of the British/UAE case as weak (Albaharna Reference Albaharna1975; Kelly Reference Kelly1956; Leatherdale Reference Leatherdale1983; Wilkinson Reference Wilkinson1991). The Blue Line was not a legal and binding boundary and Britian/UAE never demonstrated effective control east of it (Leatherdale Reference Leatherdale1983, 230). Scholars also determined that Britian/UAE legal claims were weak based on territorium nullius. In sum, then, neither state had strong legal claims to the disputed territory. The legal scholars were mixed regarding Saudi Arabia's legal claims and clearly believed that Britian/UAE had weak legal claims.

Once we had collected and coded these state-level data based on the 3-point scale provided the means for coding the final variables used in our statistical analyses. Table 1 presents all possible combinations of our coding scheme, the actor-level codings for the challenger and target's legal claims, and the resulting dispute-level coding for the final variables used in the first two stages.Footnote ⁴⁷ For example, with regard to the distribution of the state-level codings, in the 165 disputes, we code challengers as having strong legal claims 16 times, mixed legal claims 77 times, and weak legal claims 72 times. Targets, however, have strong legal claims in 56 disputes, mixed legal claims 80 times, and weak legal claims 29 times.Footnote ⁴⁸

TABLE 1.

Coding Scheme and Descriptive Statistics for Legal Claims Variables

In the first equation, we created a dummy variable (“challenger strong legal claims”) to capture the relative legal merits of the challenger's claims to the territory in question.Footnote ⁴⁹ This variable received a 1 if the challenger had superior legal claims compared to the target and a 0 otherwise (three and one in the state-level coding, see row 7, Table 1). The zero category for this variable, therefore, consists of all cases in which the challenger had weak or mixed legal claims in the state-level codings, irrespective of the target's legal claims. The point of this coding scheme is to create a variable that identifies instances in which a legal-based focal point favoring the challenger is most likely to emerge—that is, cases in which the challenger has a legal claim that is clearly superior to the target. As shown in Table 1, the challenger has strong legal claims in 14 disputes (8.5%).

In the second equation, we used the state-level codings to create a dispute-level variable (“asymmetric legal claims”) that identifies cases in which one party has a legal advantage over its adversary. This variable is not only similar to the variable used in the first equation, but it also highlights instances in which the target has a legal superiority, which occurs in 48 disputes in our data set. This variable, therefore, takes on a value of 1 if either the challenger or the target has strong legal claims, whereas their opponent has weak or mixed claims in the state-level codings (a condition that holds in 62 disputes, or roughly 38% of the time—see rows 3 and 7 in Table 1). The variable equals zero when both sides have mixed or weak claims (which happens in 103 disputes, or 62% of the time).

For the final equation, we created a variable to integrate a disputant's regime type with the asymmetric legal advantage variable used in the second equation. This variable received a coding of 1 if the dispute had an asymmetry in terms of legal advantage and the weaker state (be it the challenger or target) was a democracy. We do not restrict the regime type of the state with strong legal claims because we expect that the leader of such a state will be indifferent to the settlement venue. This is the case because any agreement, regardless of its source, will reflect his or her legal advantage. The zero category of this variable, therefore, includes disputes in which the state with weak legal claims was a nondemocracy and disputes in which both states had mixed or weak legal claims, regardless of their regime type.

Although this variable may strike some as a simple interaction term between the “asymmetric legal claims” variable and a democracy variable, this is not the case; the former describes the dyad, whereas the latter captures a characteristic of an individual party. Because the asymmetric legal claims variable does not tell us which party is legally disadvantaged, the product of it and a regime-type dummy variable would not highlight the cases of interest (i.e., where the democratic state was the party with the weaker legal claims). Although one could, theoretically, create the necessary components for a true interaction (i.e., two variables that highlight instances where the challenger and target have weak legal claims, whereas their adversaries have strong claims, which would then be interacted with variables capturing the states’ regime types), data limitations prevent us from doing so for both states.Footnote ⁵⁰