Military and Paramilitary Activities in and againstNicaragua (Nicaragua v. United States of America)

1. Case overview  

Case Title: Military and Paramilitary Activities in and against Nicaragua (Nicaragua v.  United States of America) 

Citation: Military and Paramilitary Activities in and against Nicaragua (Nicaragua v.  United States of America), Merits, Judgment, I.C.J. Reports 1986, p. 14. 

Court: International Court of Justice (ICJ), the principal judicial organ of the United  Nations. 

Bench: The case was adjudicated by the full court. The bench was presided over by  President Nagendra Singh and included Vice-President de Lacharrière and Judges Lachs,  Ruda, Elias, Oda, Ago, Sette-Camara, Schwebel, Sir Robert Jennings, Mbaye, Bedjaoui,  Ni, and Evensen. 

Note: Judge Stephen Schwebel (United States) appended a lengthy Dissenting Opinion to  the judgment. 

Date of Judgment : The judgment on the merits was delivered on 27 June 1986.

Parties Involved 

Applicant: The Republic of Nicaragua. The Sandinista government, which had  come to power in 1979, initiated the proceedings. 

Respondent: The United States of America. The Reagan Administration, which  was providing extensive support to the Contras (anti-Sandinista rebels), was the  defending party. 

2. Facts of the Case 

The case arose in the context of the Cold War and regional conflicts in Central America during  the 1980s. Following the overthrow of the Anastasio Somoza regime in 1979, the new  Nicaraguan government, dominated by the Sandinista National Liberation Front (FSLN), initially received U.S. aid. However, relations soured rapidly as the U.S. government grew concerned  about the Sandinistas’ leftist ideology, their ties to Cuba and the Soviet Union, and allegations of  their support for Marxist rebels in El Salvador (the FMLN). 

By 1981, the U.S. had terminated aid to Nicaragua and, pursuant to a presidential finding, the  Central Intelligence Agency (CIA) began to fund, train, and equip Nicaraguan exiles and rebels collectively known as the Contras to conduct military operations against the Sandinista  government.1 Nicaragua alleged that U.S. activities escalated to include: 

∙ Direct attacks by U.S. military personnel on Nicaraguan ports and oil installations; 

∙ The laying of magnetic mines in Nicaraguan internal and territorial waters, damaging  both Nicaraguan and foreign-flagged vessels; and 

∙ Comprehensive control over the Contra forces, whom Nicaragua characterized as being  de facto organs of the U.S. government.2 

The U.S. justified its actions as a lawful exercise of the inherent right of collective self defense under Article 51 of the UN Charter, arguing it was responding to armed aggression by  Nicaragua against its allies, particularly El Salvador, through the provision of weapons and  support to the FMLN.3The U.S. initially participated in the proceedings to challenge the Court’s  jurisdiction but, after this challenge failed, refused to take part in the merits phase. 

3. Issues Raised 

The Court framed the central legal questions as follows: 

1. Jurisdiction and Admissibility: Did the Court have jurisdiction to hear the case,  particularly in light of the U.S. reservation excluding disputes arising under multilateral  treaties? 
2. Merits: Had the United States, through its military and paramilitary activities in and against Nicaragua, violated its obligations under international law, specifically concerning: 

1. The principle of non-use of force? 
2. The principle of non-intervention in the affairs of another State? 
3. The sovereignty and territorial integrity of Nicaragua? 
4. The freedom of maritime commerce and navigation? 
5. Its obligations under the 1956 Treaty of Friendship, Commerce and Navigation  between the two parties? 

        4.Arguments of the Parties 

Arguments of Nicaragua: 

Nicaragua contended that the U.S. was engaged in an “unlawful use of force and intervention”  tantamount to an undeclared war.4Its core arguments were: 

∙ The U.S. had orchestrated and financed the Contra war, directly violating the prohibition  on the use of force found in both the UN Charter and customary international law. 

∙ The mining of its harbors was a blatant act of war and a breach of the 1956 Treaty of  Friendship, Commerce and Navigation. 

∙ The U.S. was responsible for the acts of the Contras under the doctrine of state  responsibility. 

∙ Nicaragua requested the Court to declare these acts unlawful and order the U.S. to cease  its activities and pay reparations for the extensive damage caused. 

Arguments of the United States: 

The U.S., in its preliminary objections and public statements, argued:5 

The Court lacked jurisdiction due to the “Vandenberg Reservation” in its 1946  declaration accepting the Court’s compulsory jurisdiction. This reservation excluded  “disputes arising under a multilateral treaty” unless all parties to the treaty affected by  the decision were also before the Court. 

Its actions were a justified and proportional response to Nicaragua’s aggressive acts  against El Salvador, constituting lawful

collective self-defense. 

It characterized the Contra forces as an independent insurgency and denied that its  support amounted to direct control. 

5. Judgment / Final Decision 

The Court found overwhelmingly in favour of Nicaragua on the merits. 

On Jurisdiction: The Court found it had jurisdiction under the compulsory jurisdiction  declarations of both states and the 1956 Treaty of Friendship. It ingeniously sidestepped  the U.S. multilateral treaty reservation by ruling that the principles of non-use of force  and non-intervention invoked by Nicaragua existed independently in customary  international law, and the case could therefore be adjudicated on that basis without  needing to apply the UN Charter directly as a multilateral treaty.6 

On the Merits: The Court held that the United States had violated international law by: 

1. Breaching its customary international law obligation not to use force against  another state (by training, arming, and funding the Contras and mining Nicaraguan waters). 
2. Violating the principle of non-intervention (by seeking to coerce Nicaragua into  changing its internal policies). 
3. Violating Nicaraguan sovereignty (through direct military attacks and  unauthorized over flights). 
4. Interrupting peaceful maritime commerce (by mining harbors). 
5. Breaching obligations under the 1956 Treaty of Friendship with Nicaragua (by  failing to ensure freedom of navigation and commerce).7

The Court rejected the U.S. justification of collective self-defense. It found no evidence  that Nicaragua had engaged in an “armed attack” against El Salvador as defined in  international law (which requires a scale and effects equivalent to a regular military  attack). The provision of arms or logistical support to opposition groups in another  country was found to be insufficient to constitute an armed attack.8Furthermore, the  Court noted that El Salvador had not officially declared itself a victim of an armed attack  or requested U.S. assistance until after the U.S. had begun its activities, invalidating the  collective self-defense claim. 

The Court ordered the U.S. to cease and refrain from all acts constituting violations of its  legal obligations and to make reparations to Nicaragua for the injury caused. 

6. Legal Reasoning / Ratio Decidendi 

The Nicaragua case is a cornerstone of modern international law for several key reasons: 

1. Separation of Customary Law from Treaty Law: The Court’s most significant  contribution was its clear demarcation between customary international law and treaty  law. It held that the core principles of the UN Charter—such as the prohibitions on the  use of force and intervention—also exist as rules of customary international law, binding  on all states regardless of their treaty commitments. This allowed the Court to adjudicate  the case without applying the UN Charter directly, thus neutralizing the U.S. multilateral  treaty reservation.9
2. Definition of “Armed Attack”: The Court introduced a crucial distinction between a  mere “frontier incident” or the provision of support for rebels, and a full-scale “armed  attack” that triggers the right to self-defense under Article 51 of the UN Charter. This  created a high threshold for justifying the use of force in response, aiming to restrict  military reprisals.10
3. The “Effective Control” Test for Attribution: The Court established a strict standard  for attributing the conduct of non-state actors (like the Contras) to a state. It held that for  8 Merits Judgment, paras. 195, 230-231. a state to be responsible for the acts of a group, it must have effective control over the  specific operations in which the unlawful acts occurred. General financing, training, and  equipping were insufficient to attribute all of the Contras’ actions to the U.S.11 This test,  though later nuanced by the International Criminal Tribunal for the former Yugoslavia  in Tadić, remains a fundamental precedent. 
4. Requirements for Collective Self-Defense: The judgment clarified the procedural  prerequisites for invoking collective self-defense: the victim state (e.g., El Salvador) must  formally declare that it has been attacked and must expressly request assistance from the  defending state (e.g., the U.S.). The Court found the evidence for this lacking. 

        7.Conclusion / Observations 

The Nicaragua judgment is a landmark of profound legal significance and equally profound  political ramifications. Legally, it stands as one of the strongest judicial affirmations of the  principles prohibiting the use of force and intervention. Its rigorous methodology for identifying  customary international law and its articulation of key jus ad bellum concepts continue to be  foundational texts in international legal scholarship and practice. 

However, the case also starkly revealed the limitations of international law in the face of power  politics. The United States, a permanent member of the UN Security Council, rejected the  judgment, vetoed draft resolutions calling for compliance, and ultimately never paid the  reparations ordered by the Court.12 This underscored the challenge of enforcing ICJ rulings  against powerful states. 

Despite this, the judgment’s legal authority remains largely untarnished. It has been extensively  cited in subsequent cases before the ICJ and other international tribunals. It serves as a powerful  legal and moral benchmark, condemning covert warfare and foreign intervention and reinforcing the framework of a rules-based international order, even if political realities sometimes prevent  its full realization. 

Reference(S): 

Franck, Thomas M., ‘Some Observations on the ICJ’s Procedural and Substantive  Innovations’ (1987) 81 American Journal of International Law 116. (A  

contemporary analysis of the decision’s legal innovations). 

Military and Paramilitary Activities in and against Nicaragua (Nicaragua v. United States of America), Merits, Judgment, I.C.J. Reports 1986, p. 14. 

Military and Paramilitary Activities in and against Nicaragua (Nicaragua v. United  States of America), Jurisdiction and Admissibility, Judgment, I.C.J. Reports 1984,  p. 392. 

Ruiz, Christy, ‘The Principle of Non-Intervention and the Nicaragua v. USA Case’ (2020)  15 Journal of International Law and International Relations 45. (A more modern  reflection on the case’s enduring significance). 

UN Security Council, Provisional Verbatim Record of the Two Thousand Seven Hundred  and Fourth Meeting, U.N. Doc. S/PV.2704 (Provisional) (28 July 1986) (record of  the US veto of a draft resolution on compliance with the judgment).