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World Court Digest

Summaries of the Decisions

Military and Paramilitary Activities in and against Nicaragua

Nicaragua v. USA

Judgment of the Court of June 27,1986

On April 9,1984, Nicaragua had initiated proceedings against the United States of America in the International Court of Justice. The action was based on the allegation that the United States had supported by its policy and actions a mercenary army, the contras, in launching attacks on the territory of Nicaragua, with the purpose of overthrowing the (Sandinista) Government of Nicaragua. By funding and assisting, covertly and overtly, the "contra" movement, the United States was using - according to Nicaragua - armed force against Nicaragua in violation of the international obligations of the United States under general international law as well as under the United Nations Charter, the OAS Charter and the bilateral United States-Nicaragua Treaty of Friendship and Commerce. In particular, it was submitted by Nicaragua that the United States was violating the prohibition of the use of force in international relations and the parallel rule on prohibition of intervention.

As a first step, the Court had decided on the interim measures requested by Nicaragua. By Order of 10 May 1984, the Court had indicated some provisional measures. By Order of 15 August 1984, the Court had then rejected the declaration to intervene under Article 63 of the Statute made by El Salvador. At the end of the first phase, the Court finally had decided in its judgment on jurisdiction and admissibility of 26 November 1984 that it had jurisdiction under Article 26 para. 2 of the Statute.

Having lost in the jurisdiction and admissibility phase, however, the United States did not cease to continue in contesting the Court's jurisdiction and decided not to appear before the Court in the proceedings on the merits. That decision made the dispute even more complicated to resolve for the Court, but the Court came to the conclusion that the United States' non-appearance did not prevent it from giving a decision in the case. A requirement to be respected in such a situation was only established by Article 53 of the Statute, according to which the Court has to satisfy itself that the claim of the party appearing is well founded in fact and law. There exists no possibility of a judgment automatically in favor of the applicant State, but the Court also has to ensure that the party which declines to appear should not be permitted to profit from its absence. This leads to a result in which a particular emphasis is placed on the active role of the Court in establishing the facts and the law relevant for deciding the case. As to determination of the facts and the production of evidence, the Court further stressed that it had freedom in estimating the value of the various elements of evidence. Although the Court found it necessary to treat these sources with caution, some types of alleged evidence like certain documentary material, evidence of witnesses presented by the applicant and certain governmental publications can contribute to corroborate the existence of a fact and can be taken into account to show whether facts are matters of public knowledge, even when they do not constitute evidence capable of proving facts.

Concerning the United States' preliminary objection that the questions of the use of force and collective self-defence raised in the case were not justiciable, the Court argued that as a "legal dispute" the case did not necessarily involve it in evaluation of political or military matters, but that the issues raised of collective self-defence were legal questions which it had competence to determine. The multilateral treaty reservation invoked by the United States, however, was confirmed by the Court to be a relevant obstacle to further exercise of its jurisdiction, at least in part. In the first (procedural) phase the Court had declared that the objection to jurisdiction based on the reservation did "not possess, in the circumstances of the case, an exclusively preliminary character" since it contained both preliminary aspects and other aspects relating to the merits and that, accordingly, it had to be dealt with at the stage of the merits. The reservation had excluded from the jurisdiction of the Court all "disputes arising under a multilateral treaty" which could affect third States which are parties to the treaty but which are not participating in the proceedings before the Court. Now, after a careful examination of the reservation, the Court concluded that it would be impossible to say that a ruling on the alleged breaches of the Charter of the United Nations as well as of the OAS Charter would not "affect" third parties, in particular El Salvador as the supposed beneficiary of the claimed actions of collective self-defence. Therefore, the jurisdiction conferred on the Court by the United States declaration under Article 36 para. 2 of the Statute did not permit the Court to entertain the claims based on violations of multilateral treaties such as the United Nations Charter and the OAS Charter. But the effect of the reservation was confined to barring the applicability of these two multilateral treaties as multilateral treaty law; as far as the application was based on principles of international customary law enshrined also in treaty law provisions, the multilateral treaty reservation did not exclude the Court's jurisdiction under the United States optional clause.

As to the facts, the Court found it established that some incidents were directly imputable to the United States. For example it was clear, after examining the facts, that, on a date in late 1983 or early 1984, the President of the United States had authorized a U.S. Government agency to lay mines in Nicaraguan ports. Accordingly, in early 1984 mines had been laid in or close to several ports of Nicaragua, either in Nicaraguan internal waters or in its territorial sea or both, and they had been laid by persons in the pay and acting on the instructions of the U.S. agency, under the supervision and with the logistic support of United States agents. Directly to be attributed to the United States were also several operations against Nicaraguan oil installations, a naval base and other facilities of the State of Nicaragua, carried out as direct actions of United States personnel, or of persons in its pay. Although it could not be proved that any United States military personnel took a direct part in the operations, United States agents undoubtedly participated in the planning, direction and support of these operations.

Quite to the contrary, the question of imputability of operations created numerous difficulties in the case of the field activities of the `contra' force. In contrast to the Nicaraguan allegation that the `contra' forces were a mercenary army created and controlled by the United States, the Court, on the basis of the available information, was notable to satisfy itself beyond doubt that the United States had "created" the 'contra' force; the Court only held it established that the United States largely financed, trained, equipped, armed and organized the FDN, one main element of the force. In the light of the evidence and material available to it, the Court was not satisfied that all the operations launched by the `contra' force, at every stage of the conflict, reflected strategy and tactics solely devised by the United States. Despite all the evidence of logistic support, the supply of intelligence information, the use of United States military advisers etc., the evidence did not warrant a finding that the United States gave direct combat support (in the sense of a direct intervention by United States combat forces) nor did it warrant a finding that the `contras' could be equated, for legal purposes, with an organ of the United States Government, or as acting on behalf of that Government. Such a direct attribution of `contra' forces to the United States Government as an organ acting on behalf of that Government would have required an extreme degree of control over the rebel forces, a degree of control that could have been inferred only from the fact of total dependence of the `contras' on United States aid; that the United States exercised such a degree of control, however, could not be deduced from the evidence collected by the Court. In conclusion, the Court took the view that the `contras' remained responsible for their acts, and in particular for the alleged violations by them of humanitarian law. United States participation, even if preponderant or decisive, in the financing, organizing, training, supplying and equipping of the `contras', the selection of its military or paramilitary targets, and the planning of the whole of its operation, in the view of the Court was still insufficient in itself for the purpose of attributing to the United States the acts committed by the `contras' in the course of their military or paramilitary operations in Nicaragua.

Concerning the measures of an economic nature complained of by Nicaragua as an indirect form of intervention in its internal affairs, the Court centred its attention on the suspension (and subsequent termination) of economic aid in the spring of 1981, the American actions to block loans to Nicaragua from international financial bodies, the reduction of the sugar import quota in September 1983 and the total trade embargo declared by executive order in May 1985.

As to the reverse factual allegations brought up by the United States in order to justify its actions as an exercise of collective self-defence, the Court had to cope with the difficulties created by the non-participation of the applicant side. There was no evidential material presented by the United States in the proceedings on the merits, and it was not easy to substantiate the alleged assistance of Nicaragua to armed rebel forces operating in neighbouring countries, particularly in El Salvador. Confined to rudimentary investigations of the facts by the Court itself, the factual basis of the allegations could not really be clarified. Evidence of military aid from or through Nicaragua to rebel forces in El Salvador remained weak, although the Court could not conclude that no transport of or traffic in arms had taken place. Thus, the Court could only take note "that the allegations of arms-trafficking are not solidly established" and that it "has not, in any event, been able to satisfy itself that any continuing flow on a significant scale took place after the early months of 1981", the date until which support for the armed opposition in El Salvador could be established as a fact by the Court.

But the Court went even further by raising the question of imputability of deliveries to the Government of Nicaragua: it noted that, having regard to the circumstances characterizing this part of Central America, it is scarcely possible for Nicaragua's responsibility for an arms traffic taking place on its territory to be automatically assumed. On the contrary, the Court considered it more realistic, and consistent with the probabilities, to recognize that an activity like arms-trafficking, if on a limited scale, may very well be pursued unbeknown to the territorial government". Accordingly, the Court came to the result that the evidence was insufficient to satisfy it that the Government of Nicaragua was responsible for any flow of arms at either period. The fact that certain trans-border military incursions into Honduras and Costa Rica were imputable to Nicaragua, however, was considered by the Court to be established.

As to the law applicable to the dispute, the Court confined its reasoning in principle to the body of customary international law. Given its approach to the United States multilateral treaty reservation, the Court had to analyze the scope and content of the customary law rules parallel to the multilateral treaty norms excluded by the American reservation. Even in cases where a treaty norm and a customary norm were to have exactly the same content, the Court did not see that as a reason to judge the customary norm as being necessarily deprived of its separate applicability. Consequently, the Court felt in no way bound to uphold customary rules only in so far as they differ from the treaty rules which it was prevented by the United States reservation from applying. The Court held that in the field in question customary law continues to exist alongside treaty law. The areas governed by the two sources of law often do not overlap exactly, and in many cases the rules also do not have the same content.

In its analysis of the concrete rules of customary law to be applied in the dispute, however, the Court decisively relied on the treaty law of the UN Charter in establishing the content of the applicable law, despite its theoretical emphasis on `opinio juris' and actual practice.

Concerning the substance of the customary rules relating to the use of force in international relations, the Court stated that the principles as to the use of force incorporated in the United Nations Charter correspond, in essentials, to those found in customary international law. In order to be satisfied that there exists in customary law an 'opinio juris' as to the binding character of the obligation to refrain from the threat or use of force, the Court mainly dealt with the practice in the United Nations. The Court argued that an 'opinio juris' may, though with all due caution, be deduced from the attitude of the Parties and the attitude of other States towards certain General Assembly resolutions, in this case particularly the "Friendly Relations Declaration" of 1970. Consent to such resolutions is, as the Court stressed, not to be understood as merely a "reiteration or elucidation" of the treaty commitment undertaken in the Charter, but has to be qualified as an acceptance of the validity of the rule declared by the resolution, here: as one of the forms of expression of `opinio juris' with regard to the principle of non-use of force.

Even more reliance on the set of rules created by the system of the United Nations Charter characterized the considerations of the Court relating to the right of self-defence. That the general rule of customary law prohibiting force allows for certain exceptions was viewed as undisputed by the Court. Already the terms of Article 51 of the United Nations Charter demonstrate that the State community starts from the assumption that there exists an "inherent right" of self-defence based in customary law which, in principle, covers both collective and individual self-defence. In defining, however, the specific conditions which may have to be met for its exercise, in addition to the conditions of necessity and proportionality, the Court distinguished "the most grave forms of the use of force" (those constituting an armed attack) from "other less grave forms". Without further attempting to base this distinction in an analysis of State practice, the Court erected its subsequent argumentation on the crucial concept of "armed attack" established by Article 51 of the UN Charter. Whether self-defence be individual or collective, its exercise is, according to the Court, subject to the State concerned having been the victim of an armed attack. To the Court there appeared to be general agreement on the nature of the acts which can be treated as constituting armed attacks. An armed attack in the construction of the Court must be understood as including not merely action by regular armed forces across an international border, but also the sending by a State of armed bands or groups on to the territory of another State, if such an operation, because of its scale and effects, would have been classified as an armed attack had it been carried out by regular armed forces. In this respect the Court quoted the definition of aggression annexed to General Assembly resolution 3314 (XXIX), which in the view of the Court may be taken to reflect customary law. Not to be included in the concept of "armed attack", however, are acts of mere assistance to rebels in the form of the provision of weapons or logistical or other support. Such assistance may, the Court believed, be regarded as a threat or use of force, or may amount to intervention in the internal or external affairs of other States, but it may not justify an action of self-defence.

Furthermore, the Court found it to be clear that it is the State which is the victim of an armed attack which must form and declare the view that it has been so attacked. The Court stated that there is no rule in customary international law permitting another State to exercise the right of collective self-defence on the basis of its own assessment of the situation; what is always required is a formal request by the State which is a victim of the alleged attack, a requirement mainly deduced by the Court from Article 3 of the OAS Charter.

Also the principle of non-intervention, which involves the right of every sovereign State to conduct its affairs without outside interference, was construed by the Court with particular reference to the numerous declarations and resolutions on that subject-matter adopted by international organizations and conferences. As regards the content of the principle, the Court noted that a prohibited intervention must be one bearing on matters in which each State is permitted, by the principle of State sovereignty, to decide freely (for example the choice of a political, economic, social and cultural system). Intervention is regarded to be wrongful when it uses, in regard to such choices, methods of coercion. The element of coercion, which in the view of the Court forms the very essence of prohibited intervention, is particularly obvious in the case of an intervention which uses force, either in the direct form of military action, or in the indirect form of support for subversive or terrorist armed activities within another State. With regard to the second question raised by the Court, namely the question whether the practice is sufficiently in conformity with the principle of non-intervention for this to be a rule of customary international law, the Court concluded, notwithstanding the fact that there had been in recent years a number of instances of foreign intervention for the benefit of opposition groups, that the practice of States does not justify the view that any general right of intervention in support of an opposition within another State exists in contemporary international law.

As a consequence of its ruling that collective self-defence requires the existence of an armed attack, the Court then had to deal with the question whether there exists a right to take counter-measures (individually as well as collectively) in response to conduct not amounting to armed attack but in breach of the principle of non-intervention. Such a right to take collective counter-measures would be analogous to the right of self-defence in the case of armed attack, but the act giving rise to the reaction, as well as the reaction itself, would be less grave, not amounting to armed attack. In the view of the Court, however, under international law in force today, States do not have a right of "collective" armed response to acts which do not constitute an "armed attack"; at the same time the Court left open the question what direct reactions are lawfully available to a State which considers itself the victim of another State's acts of intervention, possibly involving the use of force.

In dealing with the principle of respect for State sovereignty, which extends, as the Court recalled, to the internal waters and territorial sea of every State and to the airspace above its territory, the Court noted that the laying of mines within the ports as well as in the territorial sea necessarily affects the sovereignty of the coastal State. Besides, the customary right of innocent passage and the right of free access to ports, which both follow from the freedom of communications and of maritime commerce, are also infringed by such mining operations. Accordingly, the Court found it certain that interference with navigation by the laying of mines prejudices both the sovereignty of the coastal State over its internal waters, and the right of free access enjoyed by foreign ships. It was further observed by the Court that the absence of any warning or notification with regard to the mining was not only an unlawful act but also a breach of the principles of humanitarian law underlying the Hague Convention No. VIII of 1907.

Since the evidence available was insufficient for the purpose of attributing to the United States the acts committed by the `contras', the Court could not judge the alleged violations by the `contra' forces of the principles of international humanitarian law. What remained as a question, however, according to the construction of the Court, was the law applicable to the acts of the United States in relation to the activities of the `contras'. The Court analyzed that question not from the perspective of the treaty law laid down in the four Geneva Conventions of 12 August 1949, but as a question of the "fundamental general principles of humanitarian law" stated in Article 3 common to the four Geneva Conventions; in the Court's view, the Geneva Conventions are in some respects a development, and in other respects no more than the expression, of such principles. For the Court there was no doubt that these rules constitute a minimum yardstick, reflecting what the Court already in 1949 had called "elementary considerations of humanity". The Court therefore found them applicable to the dispute, with the effect that the United States was seen to be under an obligation to "respect" the Conventions and even to "ensure respect" for them, and thus not to encourage persons or groups engaged in the conflict in Nicaragua to act in violation of these "fundamental general principles".

The Court ultimately used as a legal yardstick the bilateral Treaty of Friendship, Commerce and Navigation signed at Managua on 21 January 1956. In its Judgment on jurisdiction and admissibility of 26 November 1984, the Court had concluded that it had jurisdiction also on the basis of the 1956 Treaty of Friendship, Commerce and Navigation, concerning disputes as to the interpretation or application of the treaty. The Court now found that it had to determine the meaning of the various relevant provisions, in particular the derogation clause of Article XXI para. 1 (c) and 1 (d) of the treaty.

In the final part of the Judgment, the Court then related its abstract statements on the applicable law to the factual findings it had made earlier. Beginning with the question of the lawfulness of the use of force and the alleged justification of the American actions under the right of self-defence, the Court appraised the facts as proved by the available evidence to constitute infringements of the principle of non-use of force, unless justified by circumstances which exclude their uniawfulness. The laying of mines in the internal waters and territorial sea of Nicaragua, the attacks on Nicaraguan ports, oil installations and naval bases directly imputable to the United States, but also the arming and training of the `contras' were judged by the Court to be a prima facie violation of the prohibition of the use of force, unless these actions could be justified as an exercise of the right of self-defence. To fulfil the requirements of a lawful action of collective self-defence, the Court would have had to find that Nicaragua engaged in an armed attack against El Salvador, Honduras or Costa Rica, since only such an attack could have justified reliance on the right of self-defence according to the Court's construction of the relevant principles of customary international law. With regard to El Salvador, however, the Court considered that the provision of arms to the opposition in another State did not constitute an armed attack on that State; concerning Honduras and Costa Rica, the Court stated that, in the absence of sufficient information as to the transborder incursions into the territory of those two States from Nicaragua, it was difficult to decide whether they amounted to an armed attack by Nicaragua. The Court found that neither these incursions nor the alleged supply of arms might be relied on as justifying the exercise of the right of self-defence. The Court also came to the conclusion that the procedural requirements put up for the exercise of this right, namely that the States allegedly attacked believed themselves that they were the victim of an armed attack, and expressly requested the assistance of the State claiming to act in collective self-defence, were not present. In addition, the Court regarded the United States activities as not satisfying the criteria of necessity and proportionality. The Court thus decided, by 12 votes to 3, that it had to reject the justification of collective self-defence maintained by the United States in connection with the military and paramilitary activities in and against Nicaragua, and that accordingly the United States had acted in breach of its customary law obligation not to use force against another State.

As regards the principle of non-intervention, the Court found it clearly established that the United States intended, by its support of the `contras', to coerce Nicaragua in respect of matters in which each State is permitted to decide freely. It considered that if one State, with a view to the coercion of another State, supports and assists armed bands in that State whose purpose is to overthrow its government, that amounts to an intervention in its internal affairs, whatever the political objective of the State giving support. Basing its further reasoning on the conclusion that intervention in the internal affairs of another State does not produce an entitlement to take collective counter-measures involving the use of force, and that the acts of intervention of which Nicaragua was accused could only have justified proportionate counter-measures on the part of the State which had been the victim of these acts, the Court stated that there was no justification for counter-measures taken by a third State, the United States. The Court therefore found, by 12 votes to 3, that the support given by the United States to the military and paramilitary activities of the `contras' in Nicaragua, by financial support, training, supply of weapons, intelligence and logistic support, constituted a clear breach of the obligation under customary law not to intervene in the affairs of another State. With regard to the form of "indirect" intervention which Nicaragua saw in the taking of certain economic sanctions, however, the Court felt unable to regard such action as a breach of the customary law principle of non-intervention.

Also by 12 votes to 3, the Court decided that the direct attacks on Nicaraguan ports, oil installations etc., the unauthorized overflights of Nicaraguan territory and the mining operations in Nicaraguan ports infringed the principle of respect for territorial sovereignty. The laying of mines in or near Nicaraguan ports additionally was qualified as constituting an infringement, to Nicaragua's detriment, of the freedom of communications and of maritime commerce. Concerning the mining operations, the Court further decided, by 14 votes to 1, that the United States, by failing to give notice of the existence and location of the mines laid by it, was responsible for a breach of customary principles of international humanitarian law. Also constituting a breach of its obligations under the general principles of humanitarian law was the publication and dissemination in 1983 of a manual entitled "Operaciones sicológicas en guerra de guerrillas", since by virtue of the general principles of humanitarian law the United States was bound to refrain from encouragement of groups engaged in conflict to commit violations of the humanitarian minimum standard laid down in Article 3 common to the four Geneva Conventions.

As to the other grounds mentioned by the United States in justification of its acts, the Court reaffirmed that there does not exist a new rule opening up a right of intervention by one State against another on the ground that the latter has opted for some particular ideology or political system; that alleged violations of human rights could not be taken as a justification for the use of force, since the use of force could not be the appropriate method to monitor or ensure respect for human rights; and that the alleged militarization of Nicaragua may not be accepted as justifying the use of force, since in international law there are, according to the Court, no rules, other than such rules as may be accepted by the State concerned, whereby the level of armaments of a sovereign State can be limited.

Finally, the Court turned to the claims of Nicaragua based on the Treaty of Friendship, Commerce and Navigation. Nicaragua had accused the United States of depriving the Treaty of its object and purpose and of emptying it of real content. Although the Court felt unable to regard all the acts complained of in that light, it considered that there were certain activities of the United States which were such as to undermine the whole spirit of the agreement. These were, according to the Court, the mining of Nicaraguan ports, the direct attacks on ports, oil installations etc., and the general trade embargo. By 12 votes to 3, the Court thus decided that these were acts calculated to deprive of its object and purpose the Treaty of Friendship, Commerce and Navigation of 21 January 1956. Also by 12 votes to 3, the Court decided that by the attacks on Nicaraguan ports and oil installations as well as by the declaration of a general trade embargo, the United States had acted in breach of the clause on freedom of commerce and navigation contained in Article XIX of the Treaty. The contention that by the mining of Nicaraguan ports the United States had acted in manifest contradiction with the freedom of navigation and commerce guaranteed by Article XIX of the Treaty, was upheld by the Court with 14 votes to 1.

The remaining task of the Court was to adjudge on the Nicaraguan claim concerning reparation. Alter satisfying itself that it had jurisdiction to order reparation, the Court declared as appropriate the request of Nicaragua for the nature and amount of the reparation to be determined in a subsequent phase of the proceedings, and considered only the fundamental question whether Nicaragua had a legal claim to demand compensation at all. The Court decided that the United States is under an obligation to make reparation for all injury caused to Nicaragua by the breaches of obligations under customary law and the 1956 Treaty on Friendship, Commerce and Navigation, and that the form and amount of such reparation, failing agreement between the parties, will be settled by the Court, which reserved for this purpose the subsequent procedure in the case. Finally, the Court unanimously recalled to both parties to the case the need to co-operate with the Contadora efforts in seeking a definitive and lasting peace in Central America, in accordance with the customary law principle of peaceful settlement of international disputes.