Top 10 Landmark Decisions by the International Court of Justice (ICJ)

From Borders to Rights: Exploring ICJ's Top 10 Legal Milestones

10 Key ICJ Rulings That Shaped Global Law


The International Court of Justice (ICJ), also known as the World Court, is the principal judicial organ of the United Nations. It settles legal disputes between states and gives advisory opinions to authorized UN organs and specialized agencies. The ICJ has been instrumental in shaping international law through its landmark judgments.

Whether the International Court of Justice (ICJ) can set a precedent?

The question of whether the International Court of Justice (ICJ) can set a precedent is a complex and controversial one. There is no clear answer, as different scholars have different views on the role and value of precedent in international law. Here are some of the main arguments for and against the idea of precedent in the ICJ:

For precedent:

Some scholars argue that precedent is essential for the legitimacy, consistency, predictability, and efficiency of the ICJ. They claim that precedent helps the ICJ to build its authority and persuade domestic courts and other actors to comply with its judgments. They also suggest that precedent promotes legal certainty and stability, as well as coherence and development of international law. They point out that the ICJ itself often relies on its own previous decisions and those of other international courts and tribunals, even though it is not formally bound by them. For example, one study found that the ICJ cited its own case law in 92% of its judgments and advisory opinions between 1946 and 20091. Another study proposed a weak version of horizontal stare decisis, which means that the ICJ should follow its own jurisprudence unless there are compelling reasons to depart from it. A former president of the ICJ also expressed the view that the Court’s jurisprudence is binding on itself and on other international courts and tribunals.

Against precedent:

Other scholars argue that precedent is inappropriate or unnecessary for the ICJ. They claim that precedent limits the ICJ’s flexibility and creativity, and prevents it from adapting to the changing circumstances and needs of the international community. They also suggest that precedent undermines the sovereignty and diversity of states, and imposes a uniform and rigid interpretation of international law. They point out that the ICJ is not a supreme court, but a judicial organ of the United Nations, which has a limited and consensual jurisdiction. They also note that the ICJ’s statute and rules do not mention precedent as a source of law and that the ICJ itself has stated that it is not bound by its own previous decisions or those of other international courts and tribunals. For example, in the Nicaragua case, the ICJ said that it “cannot regard itself as bound by a previous decision of its own, or of a predecessor court, if it is convinced that justice or the development of international law requires otherwise”. Another study argued that the ICJ’s use of precedent is not consistent or principled, but rather strategic and selective.

Here are some of the leading cases that helped in shaping the international law:

1. The Corfu Channel Case  UK v. Albania

Summary of the case:

This conflict resulted in three Court Judgments arising from mine explosions damaging British warships in the Corfu Channel in 1946. The United Kingdom accused Albania of laying or allowing mines after mine-clearing operations. In the first Judgment on March 25, 1948, the Court addressed jurisdiction, finding that Albania's communication on July 2, 1947, constituted voluntary acceptance. The second Judgment on April 9, 1949, held Albania responsible under international law for the explosions. The Court highlighted the challenge of proving responsibility when exclusive control hinders direct evidence, allowing a more liberal recourse to circumstantial evidence. Albania's counter-claim was partially rejected, with the Court finding the UK's innocent passage right but condemning minesweeping as a violation of Albanian sovereignty. In the third Judgment on December 15, 1949, the Court determined reparations, ordering Albania to pay £844,000 to the United Kingdom.

Voluntary Acceptance of Jurisdiction: The Court emphasized that Albania's communication constituted voluntary acceptance of jurisdiction, without specific conditions of form.

Responsibility under International Law: The Court found Albania responsible for the explosions under international law, emphasizing the knowledge of the Albanian government despite challenges in providing direct proof.

Liberal Recourse to Circumstantial Evidence: Recognizing exclusive state control hindering direct proof, the Court allowed a more liberal recourse to inferences of fact and circumstantial evidence, considering them weighty when logically linked.

Innocent Passage and Violation of Sovereignty: The Court affirmed the UK's right of innocent passage but condemned minesweeping as a violation of Albanian sovereignty, rejecting the notion of "self-help" asserted by the United Kingdom.

Reparations: In determining reparations, the Court ordered Albania to pay £844,000 to the United Kingdom.

2. Fisheries Case - Norway v. UK

Summary of the case:

The Norway-UK Fisheries Case, brought to the International Court of Justice in 1951, revolved around the delimitation of the Norwegian fishery zone in the North Sea.

The Court's judgment in this case concluded a significant maritime dispute between the United Kingdom and Norway. In 1935, Norway implemented a decree reserving fishing grounds off its northern coast exclusively for its fishermen, sparking controversy. The key question centered on the decree's validity under international law, given the complexities of Norway's coastal zone. The United Kingdom argued that some baselines set by the decree were inconsistent with the coast's general direction. However, in the judgment on December 18, 1951, the Court ruled that neither the method nor the specified baselines contradicted international law.

Validity of Territorial Waters Decree: The Court assessed the validity of Norway's 1935 decree reserving fishing grounds, examining whether its method for drawing baselines was in line with international law.

Baselines Compliance: The Court determined that the method and baselines outlined in the 1935 Decree were not contrary to international law, rejecting the United Kingdom's submissions.

Majority and Dissenting Opinions: The Court's decision, adopted by ten votes to two for the method and eight votes to four for the baselines, included declarations from Judges Alvarez, Hackworth, and Hsu Mo. Dissenting opinions were presented by Judges Sir Arnold McNair and Mr. J. E. Read, providing insights into their differing perspectives.

3. North Sea Continental Shelf Cases - Germany v. Netherlands and v. Denmark

Summary of the case:

These cases involved the continental shelf delimitation in the North Sea between Denmark and the Federal Republic of Germany and between the Netherlands and the Federal Republic of Germany. The Court, appointed through a Special Agreement, was tasked to define international law principles for subsequent delimitations. In the 1969 Judgment, the Court emphasized drawing boundary lines through mutual agreement and equitable principles, considering the natural prolongation of each party's land territory under the sea. The Court rejected the equidistance principle from the 1958 Geneva Convention, stating it wasn't a customary international law rule.

Boundary Determination by Agreement: The Court emphasized that the delimitation of the continental shelf should be based on mutual agreement between the parties, guided by equitable principles.

Equidistance Principle Rejection: The Court clarified that the equidistance principle from the 1958 Geneva Convention on the Continental Shelf was not binding, as it wasn't inherent in the basic concept of continental shelf rights and not a rule of customary international law.

Customary International Law Development: The Court acknowledged the possibility of Conventions evolving into customary international law, emphasizing the need for a fundamentally norm-creating character and extensive, virtually uniform state practice over time.

Opinio Juris Sive Necessitatis: To establish customary international law, the Court highlighted the subjective element of opinio juris sive necessitatis, requiring states to feel they are conforming to a legal obligation.

Equity Praeter Legem: The Court suggested equity beyond the law, urging parties to address incidental special features to avoid unjustifiable differences in treatment, demonstrating an application of equitable rules in the absence of clear legal provisions.

4. South West Africa Cases - South Africa v. Ethiopia, v. Liberia, and Namibia

Summary of the case:

Initiated by Ethiopia and Liberia in 1960, these cases challenged South Africa's compliance with the League of Nations Mandate for South West Africa.

The South West Africa cases (Ethiopia v. South Africa; Liberia v. South Africa) focused on the Mandate for South West Africa and South Africa's obligations as the Mandatory. In 1962, the Court dismissed South Africa's objections, affirming jurisdiction. However, in the second phase, the Court, with a tied vote, rejected the Applicant States' claims, stating they failed to establish a legal right or interest in the case.

Jurisdictional Limitation: The Court clarified that the jurisdictional clause in the Mandate did not confer substantive rights. Acceptance of the Court's jurisdiction didn't automatically grant a legal right; it only determined the competence of the Court.

Mandates System Framework: The Court emphasized that the mandates system, created under Article 22 of the League of Nations Covenant, did not grant individual League members direct rights in the conduct of mandates. Members acted through League organs.

League Members' Rights: The Court rejected the notion that League members individually possessed legal rights in the Mandate's conduct. Members' rights were limited to those conferred explicitly in the mandates.

Post-League Dissolution: The dissolution of the League didn't transfer new legal rights to individual members. Declarations by mandatories expressing willingness to adhere to mandates post-dissolution did not create new legal rights.

Literal Interpretation: The Court dismissed a broad interpretation of the jurisdictional clause, emphasizing that such clauses, including the Mandate's, were procedural, not substantive, and didn't confer automatic legal rights.

Necessity Argument Rejection: The Court rejected the argument that individual members needed legal rights for the Mandate's efficacy, emphasizing that such an argument relied on post-factum considerations and lacked a basis in the law.

No Actio Popularis: The Court asserted that international law didn't recognize an actio popularis, where any member could take legal action for a public interest. Rights had to be specific and legally established.

In conclusion, the Court rejected the claims of Ethiopia and Liberia, asserting that the Applicants failed to prove a legal right or interest in the Mandate for South West Africa.

5. Military Activities in and against Nicaragua - Nicaragua v. USA

Summary of the case:

On April 9, 1984, Nicaragua filed a case against the United States, leading to a landmark judgment by the International Court of Justice (ICJ) on November 26, 1984. The ICJ's ruling highlighted several legal principles:

Sovereignty and Non-Intervention: The ICJ emphasized the importance of respecting Nicaragua's sovereignty and political independence, in line with the principles prohibiting the threat or use of force and non-intervention in a state's domestic affairs.

Jurisdiction and Admissibility: The ICJ affirmed its jurisdiction to address the case and deemed Nicaragua's application admissible. This underscored the significance of proper legal procedures and the adherence to international law.

Prohibition of the Use of Force: The judgment rejected the justification of collective self-defense, condemning the U.S. for military and paramilitary activities that violated customary international law's prohibition of the use of force against another state.

Humanitarian Law: The ICJ considered the dissemination of a manual to Contra forces as an encouragement of acts contrary to humanitarian law. It clarified that responsibility for such acts rested with the Contras, but the U.S. could be implicated if it exercised effective control.

Violation of Treaties: The Court found the U.S. in breach of the 1956 Treaty of Friendship, Commerce, and Navigation with Nicaragua, emphasizing the importance of honoring international agreements.

Reparation: The U.S. was ordered to cease its unlawful acts immediately and make reparations for the injury caused to Nicaragua. The form and amount of reparations would be determined by the Court if the parties couldn't reach an agreement.

Despite the ICJ's call, the U.S. refused compliance, citing withdrawal from the ICJ's compulsory jurisdiction. The UN General Assembly urged U.S. compliance in a non-binding resolution. 

In essence, the judgment reinforced key principles of international law, including sovereignty, non-intervention, the prohibition of the use of force, and the importance of treaty obligations.

6. Western Sahara Case

Summary of the case:

In the Western Sahara Case, an advisory opinion was sought by the United Nations General Assembly regarding the international law status of Western Sahara. The International Court of Justice (ICJ) concluded that the people of Western Sahara possessed the right to self-determination. Additionally, the ICJ determined that Morocco did not hold sovereignty over the territory. The ICJ ruled:

Territorial Status: The ICJ rejected the notion that Western Sahara was terra nullius (belonging to no one) during Spain's colonization.

Legal Ties: The court acknowledged legal ties of allegiance between the Sultan of Morocco and certain tribes in Western Sahara. Similar ties were identified between the Mauritanian entity and the territory. However, these ties did not imply territorial sovereignty or impact self-determination.

Principle of Self-Determination: The ICJ emphasized that the legal ties identified did not hinder the application of the principle of self-determination for the people of Western Sahara. The 1960 UN resolution on decolonization and self-determination remained applicable.

Despite the ICJ's findings, the interested parties largely disregarded the decisions. The subsequent events, including the Madrid Accords and military interventions, led to the complex geopolitical situation in Western Sahara.

7. Fisheries Jurisdiction Case (United Kingdom v. Iceland)

Summary of the case:

In 1972, the International Court of Justice addressed a fisheries dispute between Iceland and the United Kingdom. Iceland sought to extend its exclusive fishing jurisdiction from 12 to 50 nautical miles. Despite Iceland's objection and non-participation, the Court asserted jurisdiction. In 1974, it ruled that Iceland's unilateral extension of fishing rights was not binding on the UK, emphasizing the need for negotiations. The Court recognized two customary law principles: the concept of a fishery zone, generally accepted up to a 12-mile limit, and the idea of preferential rights for coastal states with special dependence on coastal fisheries. The ruling underscored the obligation for equitable resource exploitation and conservation in bilateral negotiations.

Exclusive Fishing Jurisdiction: The case underscores the concept of exclusive fishing jurisdiction, allowing states to claim rights independently beyond their territorial sea.

Unilateral Extension: The ruling establishes that a unilateral extension of fishing rights, as demonstrated by Iceland, must be subject to international legal scrutiny and is not automatically binding on other nations.

Bilateral Negotiations: Emphasizes the obligation of nations to engage in good-faith bilateral negotiations to achieve an equitable solution to disputes, particularly in matters related to fisheries.

Preferential Rights: Acknowledges the concept of preferential rights for coastal states with a special dependence on coastal fisheries, recognizing their entitlement to a significant share in the distribution of fishing resources.

Customary Law Principles: Affirms the acceptance of certain principles as part of customary law, including the concept of a fishery zone and preferential rights for coastal states, which nations are expected to adhere to in resolving fisheries-related disputes.

8. Nuclear Tests (Australia v. France; New Zealand v. France)

Summary of the case:

Australia and New Zealand (Plaintiffs) sought an injunction from the International Court of Justice (ICJ) to stop France (Defendant) from conducting atmospheric nuclear tests in the South Pacific. France, after completing the tests, declared no plans for further testing. The central issue was whether unilateral declarations could create legal obligations.

Unilateral Acts and Legal Obligations: The case establishes that declarations through unilateral acts can indeed result in legal obligations. The President of France's statements were deemed a commitment by the state, holding legal significance.

State Engagement: Recognizes that statements by a State's officials, like those made by the President of France, can constitute an engagement of the State and carry legal significance.

Jurisdiction of International Court: The ICJ had jurisdiction to address matters related to unilateral declarations, emphasizing its role in overseeing and adjudicating international disputes.

General Nature: Emphasizes that the legal impact of unilateral acts is based on their general nature and characteristics, irrespective of the specific state initially addressed.

Achievement of Object: The Court considered the objective of Australia and New Zealand achieved since France publicly declared the cessation of further nuclear tests. This reflects the court's attention to the practical impact and accomplishment of the legal actions brought forth.


The Court dismissed the application based on France's unilateral declarations, considering them legally binding and the objectives of Australia and New Zealand achieved.

9. Legal consequences of the construction of the wall in Palestine

Summary of the case:

The General Assembly, in 2003, sought an advisory opinion from the International Court of Justice (ICJ) on the legal consequences of Israel's construction of a wall in the Occupied Palestinian Territory. The ICJ, after considering jurisdiction and the propriety of the opinion, concluded that the wall and its associated measures breached international law. The Court found violations of the right to self-determination, liberty of movement, and various humanitarian and human rights principles. Israel was directed to cease construction, dismantle parts within Palestinian Territory, and provide reparations. States were obligated not to recognize the illegal situation and take action to end impediments to Palestinian self-determination.

Unilateral Advisory Opinion: The case establishes the authority of the General Assembly to seek an advisory opinion from the ICJ on matters falling within its competence.

Jurisdiction of ICJ: The ICJ clarified its jurisdiction, emphasizing the broader frame of reference beyond bilateral disputes and its role in addressing issues directly concerning the United Nations.

International Humanitarian Law: The Court relied on international humanitarian law, including the Fourth Geneva Convention, to assess the legality of Israel's actions in the Occupied Palestinian Territory.

Right to Self-Determination: The case underscores the importance of respecting the right to self-determination, emphasizing its breach due to the construction of the wall.

Reparation for Damages: Israel was mandated to provide reparation for damages suffered by individuals affected by the wall's construction.

State Obligations: All states were obligated not to recognize the illegal situation resulting from the wall's construction and to ensure compliance with international humanitarian law.

Role of the United Nations: The General Assembly and the Security Council were urged to consider further actions to address the illegal situation, promoting efforts for a negotiated solution based on international law.

Contextual Consideration: The Court emphasized placing the construction of the wall in a broader context, highlighting the obligations of both Israel and Palestine to comply with international humanitarian law and relevant Security Council resolutions.

Legal Ramifications: The judgment was invoked in a 2006 case brought by Al-Haq against the UK government, urging the cessation of export licenses to Israel based on the ICJ Advisory Opinion. The case was dismissed in 2008.

United Nations Resolution: The ICJ judgment was referred to in a United Nations General Assembly Resolution in December 2011, underscoring its significance in international discourse.

10. Legal Consequences for States of the Continued Presence of South Africa in Namibia (South West Africa) notwithstanding Security Council Resolution 276 (1970)

Summary of the case:

In 1971, the International Court of Justice (ICJ) declared South Africa's continued presence in Namibia as illegal, urging its immediate withdrawal. The General Assembly had terminated the Mandate for South West Africa in 1966, revoking South Africa's administration rights. The ICJ emphasized the illegality of South Africa's acts concerning Namibia post-Mandate termination. States were obligated to recognize this illegality, refraining from actions implying support. The ICJ emphasized the principle that illegal acts should not gain legal recognition, safeguarding the basic human rights of Namibia's inhabitants.

Termination of Mandate: The General Assembly's decision to terminate the Mandate for South West Africa established a legal precedent for ending colonial mandates.

Illegality Doctrine: The ICJ invoked the principle of ex injuria jus non oritur, asserting that acts contrary to international law cannot gain legal recognition.

Withdrawal Obligation: The ICJ's ruling established a legal principle that an occupying power, post-mandate termination, is under an obligation to immediately withdraw its administration.

Recognition of Illegality: States were legally obliged to recognize the illegality of South Africa's presence in Namibia and refrain from actions implying support.

International Human Rights: The ICJ emphasized the application of basic human rights, particularly regarding birth, marriage, and death certification, to inhabitants of the occupied territory.

Preventing Perpetuation: The ICJ's emphasis on not granting legal recognition to illegal acts serves as a precedent to prevent the perpetuation of unlawful actions by states.

Principle of Consent: The case underlines the principle that consent is vital in legal settlements, reinforcing the idea that individuals or territories cannot be bound by actions without their consent.


"In conclusion, the International Court of Justice has played a pivotal role in shaping the landscape of international law through a series of landmark decisions. From territorial disputes to human rights matters, the ICJ has been a beacon of justice, providing crucial interpretations and setting precedents for the global community. As we reflect on these 10 leading decisions, it becomes evident that the ICJ's impact extends far beyond individual cases — it contributes to the development of a more just and harmonious world. The court's unwavering commitment to upholding international legal principles serves as a testament to the power of diplomacy and the pursuit of justice on a global scale."

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