International Court of Justice (ICJ)

Introduction

The International Court of Justice (ICJ) is the principal judicial organ of the United Nations. It was established by the UN Charter and operates in accordance with the Statute of the International Court of Justice, which forms an integral part of the Charter.

The ICJ is based at the Peace Palace in The Hague, Netherlands, and is the principal international court dealing with disputes between States.

Its functions can broadly be divided into two categories:

• Contentious jurisdiction — deciding legal disputes between States through binding judgments.
• Advisory jurisdiction — giving advisory opinions on legal questions referred to it by authorised UN organs and specialised agencies.

The ICJ is therefore one of the most important institutions for the judicial settlement of international disputes.

Establishment and Legal Basis

The ICJ derives its authority primarily from:

• UN Charter, Article 92
• Statute of the International Court of Justice
• Rules of Court
• UN Charter, Article 93 concerning membership of the Statute
• UN Charter, Article 94 concerning compliance with judgments
• UN Charter, Article 96 concerning advisory opinions

Article 92 of the UN Charter

Article 92 provides that the ICJ is the principal judicial organ of the United Nations.

It also states that the Court functions in accordance with its Statute, which is based upon the Statute of the Permanent Court of International Justice and forms an integral part of the UN Charter.

Seat of the Court

The ICJ has its seat at the Peace Palace in The Hague, Netherlands.

The Hague is therefore commonly described as the judicial centre of international law.

Composition of the ICJ

The Court consists of 15 judges.

Election of Judges

Judges are elected by:

• the General Assembly, and
• the Security Council.

They are elected independently by the two organs.

A candidate must obtain an absolute majority in both the General Assembly and the Security Council.

Term

Each judge serves a nine-year term and may be re-elected.

The terms are staggered so that approximately one-third of the Court is elected every three years.

Qualifications of Judges

Under Article 2 of the ICJ Statute, judges should be persons of:

• high moral character; and
• qualifications required in their respective countries for appointment to the highest judicial offices; or
• recognised competence in international law.

The Court therefore seeks both legal expertise and judicial independence.

Independence of Judges

Judges do not represent their States in the manner of diplomatic representatives.

Once elected, they serve as independent judges and are expected to decide cases according to international law.

This distinction is important:

ICJ Judge ≠ State Representative

Nationality of Judges

No two judges may be nationals of the same State.

However, a State may have a judge of its nationality sitting on the Court.

The presence of a judge of a party’s nationality does not mean that the judge acts as that State’s representative.

Ad Hoc Judges

A party to a case may appoint an ad hoc judge where the Court does not already include a judge of its nationality.

This mechanism is intended to ensure equality between parties in the composition of the Court.

An ad hoc judge participates in the case with the same judicial responsibilities as the other judges.

Presidency and Vice-Presidency

The judges elect:

• a President, and
• a Vice-President.

They serve three-year terms and may be re-elected.

The President has important procedural responsibilities and ordinarily presides over hearings and deliberations.

Jurisdiction of the ICJ

The ICJ’s jurisdiction is one of the most important examination topics.

The Court does not automatically have jurisdiction over every international dispute.

Its contentious jurisdiction is fundamentally based upon State consent.

This reflects the consensual nature of international law.

Basic Principle

No State can generally be brought before the ICJ in a contentious case without a valid basis of jurisdiction.

Consent may be given in different ways.

Forms of State Consent

Special Agreement

States may jointly agree to submit a particular dispute to the Court.

This is known as a special agreement or compromis.

Example:

State A + State B → Agreement → ICJ

The parties themselves determine that the dispute should be submitted to the Court.

Compromissory Clause

A treaty may contain a provision stating that disputes concerning the interpretation or application of the treaty may be submitted to the ICJ.

Such a provision is commonly called a compromissory clause.

Therefore:

Treaty → Jurisdiction Clause → ICJ

Optional Clause Declaration

Under Article 36(2) of the ICJ Statute, States may declare that they recognise as compulsory, in relation to any other State accepting the same obligation, the jurisdiction of the Court over specified categories of legal disputes.

This is commonly known as the optional clause system.

Forum Prorogatum

Jurisdiction may also arise where a State that did not initially accept jurisdiction subsequently accepts it in relation to a particular dispute.

This is known as forum prorogatum.

Reciprocity

Under the optional clause system, declarations operate on the basis of reciprocity.

A State can generally invoke another State’s acceptance only to the extent that the jurisdictional commitments of the two States overlap.

Therefore:

State A’s declaration + State B’s declaration → Common jurisdictional scope

Subject-Matter Jurisdiction

The ICJ deals with legal disputes between States.

Under Article 36(1) of the ICJ Statute, jurisdiction includes matters specially provided for in:

• treaties and conventions in force;
• the Statute;
• other bases of consent recognised by international law.

Parties Before the ICJ

Only States may be parties in contentious proceedings before the ICJ.

Under Article 34(1) of the ICJ Statute:

“Only states may be parties in cases before the Court.”

Therefore:

Individuals → Cannot directly bring contentious cases before ICJ

Companies → Cannot directly bring contentious cases

NGOs → Cannot directly bring contentious cases

States → May be parties

This distinguishes the ICJ from certain international human-rights courts and tribunals that permit individual applications.

UN Member States and the ICJ

Under Article 93(1) of the UN Charter, all UN Members are automatically parties to the Statute of the ICJ.

Non-UN members may also become parties to the Statute under the conditions determined by the General Assembly upon recommendation of the Security Council.

Important Distinction

Being a party to the ICJ Statute does not automatically mean that a State has accepted the Court’s compulsory jurisdiction over every dispute.

A separate jurisdictional basis is generally required.

Contentious Jurisdiction

Contentious jurisdiction refers to cases involving a legal dispute between States.

The Court determines:

• whether it has jurisdiction;
• whether the claim is admissible;
• what international law requires;
• whether a State has violated an international obligation;
• what legal consequences follow.

The proceedings culminate in a judgment.

Advisory Jurisdiction

The second major function of the ICJ is its advisory jurisdiction.

Under Article 65 of the ICJ Statute, the Court may give an advisory opinion on a legal question at the request of an authorised body.

Article 96 of the UN Charter

The General Assembly and Security Council may request advisory opinions from the ICJ on legal questions.

Other UN organs and specialised agencies may also request advisory opinions concerning legal questions arising within the scope of their activities, subject to the relevant authorisation.

Contentious vs Advisory Jurisdiction

Contentious Jurisdiction	Advisory Jurisdiction
Legal dispute between States	Legal question referred by authorised body
States are parties	Requesting UN organ/agency is not a party in the same sense
Results in judgment	Results in advisory opinion
Judgment binding on parties	Advisory opinion generally not binding
Based on jurisdictional consent	Based on authority to request and Court’s discretion
Article 36 important	Articles 65–68 important

Sources of International Law Applied by the ICJ

Article 38(1) of the ICJ Statute is one of the most important provisions for examinations.

The Court applies:

International Conventions

International treaties and conventions establish rules expressly recognised by the contesting States.

International Custom

The Court applies international custom as evidence of a general practice accepted as law.

General Principles of Law

The Court applies general principles of law recognised by nations.

Judicial Decisions and Teachings

Judicial decisions and the teachings of the most highly qualified publicists are used as subsidiary means for determining rules of law.

Article 38 Formula

Remember:

Treaties + Custom + General Principles

+ Judicial Decisions + Teachings as Subsidiary Means

Equity

Under Article 38(2), the Court may decide a case ex aequo et bono if the parties agree.

This means the Court may decide according to considerations of fairness rather than strictly applying existing legal rules, but only where the parties expressly agree.

Procedure Before the ICJ

An ICJ case generally passes through several stages.

Application / Special Agreement

↓

Written Pleadings

↓

Preliminary Objections, if raised

↓

Jurisdiction and Admissibility

↓

Oral Hearings

↓

Deliberation

↓

Judgment

↓

Implementation / Compliance

The exact procedure varies according to the circumstances of the case.

Written Proceedings

The written phase may involve documents such as:

• Memorial;
• Counter-Memorial;
• Reply;
• Rejoinder.

The Court determines the procedural timetable.

Oral Proceedings

After written pleadings, the Court may conduct public hearings.

Agents and counsel for the States present:

• arguments;
• evidence;
• legal authorities;
• responses to opposing arguments.

Preliminary Objections

A respondent State may challenge:

• jurisdiction;
• admissibility;
• other preliminary matters.

The Court may decide these objections before considering the merits.

Important Point

Jurisdiction comes before merits.

The Court must establish that it has authority to decide the dispute.

Provisional Measures

Under Article 41 of the ICJ Statute, the Court has the power to indicate provisional measures where circumstances so require to preserve the respective rights of the parties.

These measures are intended to prevent serious harm while the case is pending.

Example

If there is a risk that one State may take irreversible action affecting disputed territory or rights, the Court may indicate provisional measures.

Binding Nature of Provisional Measures

The ICJ has established that its provisional measures are legally binding.

A major authority is:

LaGrand (Germany v United States)

The Court held that provisional measures indicated under Article 41 have binding effect.

Judgment of the Court

The Court’s judgment is the final decision in a contentious case.

Under Article 59 of the ICJ Statute, the decision of the Court has binding force between the parties and in respect of that particular case.

Therefore:

ICJ Judgment → Binding on parties

but

ICJ Judgment → Not a universal binding precedent for all States

Finality of Judgment

Under Article 60, the judgment is final and without appeal.

However, the Statute provides limited mechanisms for:

• interpretation of a judgment; and
• revision in specified circumstances.

Interpretation of Judgment

Under Article 60, a dispute regarding the meaning or scope of a judgment may be referred to the Court for interpretation.

Revision of Judgment

Under Article 61, revision may be sought where a decisive fact was unknown to the Court and to the party seeking revision when the judgment was given, subject to the strict conditions of the provision.

Revision is therefore an exceptional remedy.

Compliance with ICJ Judgments

Article 94 of the UN Charter is important.

Under Article 94(1), each UN Member undertakes to comply with the decision of the ICJ in any case to which it is a party.

Under Article 94(2), if a party fails to perform its obligations under a judgment, the other party may have recourse to the Security Council.

The Security Council may make recommendations or decide upon measures where it deems necessary.

Does the ICJ Have Its Own Police Force?

No.

The ICJ does not possess an independent police or enforcement force.

Its effectiveness therefore depends significantly on:

• State compliance;
• international political pressure;
• the Charter framework;
• diplomatic consequences.

Evidence and Fact-Finding

The ICJ may consider various forms of evidence, including:

• documentary evidence;
• maps;
• diplomatic correspondence;
• witness material;
• expert evidence;
• State practice;
• official records.

The Court evaluates evidence according to the circumstances of each case.

Intervention by Third States

A State that is not originally a party may seek to intervene in proceedings under certain circumstances.

Article 62

A State may request permission to intervene if it considers that it has an interest of a legal nature which may be affected by the decision in the case.

Article 63

Where the construction of a convention to which States other than the parties are parties is in question, those States have a right to intervene in accordance with the Statute.

Diplomatic Protection and the ICJ

States may bring claims before the ICJ through diplomatic protection in appropriate circumstances.

An individual does not personally appear as the claimant in a contentious ICJ case.

Instead:

Individual injured by another State

↓

State of nationality

↓

Diplomatic protection

↓

State brings international claim

↓

ICJ, if jurisdiction exists

The Mavrommatis principle is important in understanding the traditional character of diplomatic protection.

Important ICJ Cases

Corfu Channel Case

United Kingdom v Albania

Important for:

• State responsibility;
• territorial sovereignty;
• evidence;
• innocent passage;
• judicial settlement.

It was one of the ICJ’s earliest contentious cases.

Nottebohm Case

Liechtenstein v Guatemala

Important for:

• nationality;
• diplomatic protection;
• genuine connection.

The case is particularly important for understanding the relationship between nationality and diplomatic protection.

North Sea Continental Shelf Cases

Federal Republic of Germany v Denmark; Federal Republic of Germany v Netherlands

Important for:

• customary international law;
• continental shelf delimitation;
• treaty principles;
• equitable principles.

The Court examined the formation and evidence of customary international law.

Barcelona Traction Case

Belgium v Spain

Important for:

• diplomatic protection;
• corporations;
• nationality;
• obligations erga omnes.

The Court famously discussed obligations owed to the international community as a whole.

Nicaragua v United States

Military and Paramilitary Activities in and against Nicaragua

Important for:

• use of force;
• non-intervention;
• self-defence;
• customary international law;
• State responsibility.

It is one of the most significant ICJ cases concerning the relationship between treaty and customary international law.

United States Diplomatic and Consular Staff in Tehran

Important for:

• diplomatic immunity;
• consular relations;
• State responsibility;
• protection of diplomatic personnel.

Gabčíkovo-Nagymaros Project

Hungary v Slovakia

Important for:

• necessity;
• treaty law;
• environmental considerations;
• State responsibility;
• termination and suspension of treaties.

Bosnia Genocide Case

Bosnia and Herzegovina v Serbia and Montenegro

Important for:

• Genocide Convention;
• State responsibility;
• prevention of genocide;
• attribution;
• international judicial settlement.

LaGrand

Germany v United States

Important for:

• Article 41;
• provisional measures;
• their binding character;
• Article 94 of the UN Charter.

Jadhav Case

India v Pakistan

Important for:

• consular access;
• Vienna Convention on Consular Relations;
• diplomatic protection;
• individual rights within the context of consular relations.

ICJ and International Law

The ICJ has played a major role in clarifying international law concerning:

• State responsibility;
• use of force;
• self-defence;
• territorial sovereignty;
• maritime delimitation;
• treaty interpretation;
• diplomatic relations;
• nationality;
• genocide;
• customary international law;
• environmental obligations;
• human rights-related questions.

Its judgments and reasoning have significantly contributed to the development and clarification of international law.

ICJ vs Permanent Court of Arbitration

ICJ	PCA
Permanent international court	Permanent arbitral institution
15 permanent judges	Case-specific arbitral tribunals
Principal judicial organ of UN	Independent intergovernmental arbitral institution
States appear as parties	States and other entities may participate depending on applicable rules
Judicial procedure	Arbitration
Judgments	Arbitral awards
Jurisdiction based on consent	Jurisdiction based on consent
Located in Peace Palace	Based at Peace Palace

ICJ vs Arbitration

ICJ	International Arbitration
Permanent court	Tribunal constituted for dispute
15 elected judges	Arbitrators selected under applicable agreement
UN principal judicial organ	Not a UN judicial organ
Formal judicial procedure	Generally more flexible
Judgment	Award
Public institutional framework	Greater procedural party control
Consent required for jurisdiction	Consent required

ICJ vs International Criminal Court

These two courts should not be confused.

ICJ	ICC
International Court of Justice	International Criminal Court
Principal judicial organ of UN	Independent international criminal court
Cases primarily between States	Cases concerning individuals
State responsibility	Individual criminal responsibility
Civil/inter-State disputes	International crimes
Genocide may arise as State responsibility	Genocide may be prosecuted as individual crime

Easy Memory Trick

ICJ → States

ICC → Individuals

Importance of the ICJ

The ICJ is important because it:

• provides peaceful judicial settlement;
• clarifies international law;
• resolves disputes between States;
• contributes to the development of customary international law;
• provides authoritative judicial reasoning;
• offers advisory opinions on important legal questions;
• strengthens the rule of law in international relations.

Limitations of the ICJ

Consent-Based Jurisdiction

The Court cannot simply assume jurisdiction over every international dispute.

Only States in Contentious Cases

Individuals and private entities cannot generally initiate contentious proceedings directly.

Enforcement Difficulties

The Court lacks its own enforcement machinery.

Political Context

Even judicial disputes can arise within politically sensitive international situations.

Time and Cost

Complex cases can require years of written and oral proceedings and substantial resources.

Reservations and Jurisdictional Limits

Treaty reservations and limitations contained in declarations may restrict the Court’s jurisdiction.

Important Articles for Examination

Provision	Importance
UN Charter Article 92	ICJ as principal judicial organ
UN Charter Article 93	States as parties to the Statute
UN Charter Article 94	Compliance with ICJ judgments
UN Charter Article 96	Advisory opinions
ICJ Statute Article 1	Status of the Court
Article 2	Qualifications of judges
Article 3	Number and nationality of judges
Article 4	Election procedure
Article 13	Nine-year terms
Article 34	States as parties
Article 36	Jurisdiction
Article 38	Sources of international law
Article 41	Provisional measures
Article 59	Binding force of judgments
Article 60	Finality and interpretation
Article 61	Revision
Article 62	Intervention
Article 63	Intervention concerning treaty interpretation
Article 65	Advisory jurisdiction

Complete ICJ Structure

International Court of Justice

↓

Principal Judicial Organ of the UN

↓

15 Judges

↓

Two Major Functions

↓

Contentious Jurisdiction

→ State vs State

→ Consent-based jurisdiction

→ Judgment

→ Binding on parties

OR

↓

Advisory Jurisdiction

→ Legal question

→ Authorised UN organ / specialised agency

→ Advisory opinion

→ Generally non-binding

ICJ Jurisdiction Flowchart

International dispute

↓

Are the parties States?

↓

Yes

↓

Is there a valid basis of ICJ jurisdiction?

↓

Special Agreement / Treaty Clause / Optional Clause / Other Accepted Basis

↓

ICJ examines jurisdiction

↓

If jurisdiction established

↓

Merits

↓

Judgment

↓

Binding on parties – Article 59

↓

Compliance – Article 94 UN Charter

Quick Revision

Question	Answer
Full form	International Court of Justice
Status	Principal judicial organ of the UN
Established under	UN Charter
Statute	Integral part of UN Charter
Seat	Peace Palace, The Hague
Judges	15
Term	9 years
Election	General Assembly + Security Council
Main jurisdiction	Contentious + Advisory
Contentious parties	States
Main jurisdiction principle	State consent
Special agreement	Direct consent for particular dispute
Treaty clause	Compromissory clause
Optional clause	Article 36(2)
Main sources	Article 38
Provisional measures	Article 41
Binding force	Article 59
Finality	Article 60
Revision	Article 61
Intervention	Articles 62–63
Advisory jurisdiction	Article 65 Statute / Article 96 Charter
Compliance	Article 94 Charter
Main limitation	Consent + enforcement

Key Exam Points

• The ICJ is the principal judicial organ of the United Nations.
• It is governed by the UN Charter and its Statute.
• It has 15 judges, elected by the General Assembly and Security Council.
• Judges serve nine-year terms.
• Only States may be parties to contentious cases before the ICJ.
• ICJ contentious jurisdiction is fundamentally based on State consent.
• Consent may arise through a special agreement, treaty clause, optional clause declaration or other recognised basis.
• Article 36 of the Statute is central to jurisdiction.
• Article 38 identifies the principal sources applied by the Court.
• Article 41 concerns provisional measures.
• Provisional measures are legally binding according to the Court’s jurisprudence, particularly LaGrand.
• Article 59 establishes the binding force of judgments between the parties and in the particular case.
• Article 60 establishes the finality of judgments.
• Article 61 provides for revision under strict conditions.
• Article 65 concerns advisory opinions.
• Article 94 of the UN Charter concerns compliance with judgments.
• The ICJ does not have its own police force.
• The Court contributes significantly to the clarification and development of international law.
• ICJ → State responsibility and inter-State disputes
• ICC → Individual criminal responsibility

Conclusion

The International Court of Justice occupies a central position in the international legal system. As the principal judicial organ of the United Nations, it provides States with an institutional mechanism for resolving legal disputes through the application of international law.

Its authority rests fundamentally on State consent, making jurisdiction one of the most important aspects of ICJ proceedings. The Court exercises both contentious jurisdiction, resulting in binding judgments between States, and advisory jurisdiction, through which it provides legal opinions to authorised UN organs and agencies.

Through cases concerning territorial disputes, use of force, treaty interpretation, State responsibility, diplomatic relations, genocide and customary international law, the ICJ has made a substantial contribution to the development and clarification of international law.

For examination purposes, the core framework is:

ICJ = Principal Judicial Organ of UN

15 Judges → 9-Year Terms

Contentious → State vs State → Consent → Binding Judgment

Advisory → Legal Question → Advisory Opinion

Article 36 → Jurisdiction

Article 38 → Sources

Article 41 → Provisional Measures

Article 59 → Binding Force

Article 94 UN Charter → Compliance

Article 96 UN Charter → Advisory Opinions