Judicial Decisions and Juristic Writings

Judicial decisions and juristic writings are important subsidiary means for determining rules of Public International Law. They help courts and States identify, interpret and clarify existing international legal rules. Unlike treaties, international custom and general principles of law, they are not generally regarded as primary sources of international law.

Article 38(1)(d) of the Statute of the International Court of Justice recognises “judicial decisions” and the “teachings of the most highly qualified publicists” as subsidiary means for determining rules of law.

Meaning of Judicial Decisions

Judicial decisions are judgments, orders, advisory opinions and other decisions of courts and tribunals dealing with questions of international law.

They may assist in determining:

• the existence of an international legal rule;
• the interpretation of treaties;
• the existence of customary international law;
• the application of general principles;
• State responsibility;
• jurisdiction;
• legal consequences of internationally wrongful acts.

Judicial decisions are particularly valuable because international law develops through the interpretation and application of legal rules by international courts and tribunals.

However, a judicial decision does not automatically create a universally binding rule of international law.

Article 38(1)(d) of the ICJ Statute

Article 38(1)(d) identifies:

Judicial decisions and the teachings of the most highly qualified publicists of the various nations

as subsidiary means for the determination of rules of law.

This distinction is important.

Article 38(1)(a)–(c) identifies:

• international conventions;
• international custom;
• general principles of law.

Article 38(1)(d), on the other hand, identifies materials that assist in determining and understanding those rules.

Judicial Decisions as a Subsidiary Means

Judicial decisions may help establish what the applicable law is.

A court may examine previous decisions to determine:

• whether a customary rule exists;
• how a treaty provision has been interpreted;
• how a general principle has been applied;
• how international responsibility has been determined;
• how jurisdictional questions have previously been addressed.

Previous decisions therefore have considerable persuasive authority, even though they do not generally operate as universal binding precedent.

Article 59 of the ICJ Statute

Article 59 of the ICJ Statute provides that:

“The decision of the Court has no binding force except between the parties and in respect of that particular case.”

This establishes an important limitation on the authority of ICJ judgments.

An ICJ judgment is binding upon the parties to that particular dispute, but it does not automatically become binding precedent for every State.

Judicial Decisions and Precedent

The doctrine of stare decisis requires courts to follow applicable judicial precedents.

International law does not generally apply stare decisis in the same manner as some domestic common-law systems.

The ICJ frequently considers its earlier judgments and may follow previous reasoning where appropriate, but it is not formally bound by its previous decisions as a domestic court may be bound by precedent.

Therefore:

ICJ judgments are binding between the parties in the particular case but are not generally binding precedents for future cases.

Types of Judicial Decisions

International Court of Justice

The ICJ is the principal judicial organ of the United Nations.

Its judgments and advisory opinions are highly influential in determining and explaining international law.

Permanent Court of International Justice

The Permanent Court of International Justice operated under the League of Nations and made important contributions to the development of international law.

Its decisions continue to be relevant to the study of international legal principles.

International Arbitral Tribunals

International arbitral tribunals have contributed to areas including:

• territorial disputes;
• maritime delimitation;
• State responsibility;
• investment law.

International Criminal Tribunals

International criminal tribunals have contributed to the development and interpretation of rules relating to:

• genocide;
• crimes against humanity;
• war crimes;
• individual criminal responsibility.

National Courts

Domestic courts may also decide questions involving international law.

Their judgments can provide evidence of:

• State practice;
• treaty interpretation;
• customary international law;
• domestic application of international rules.

Their significance depends upon the particular legal issue and circumstances.

Judicial Decisions and Customary International Law

Judicial decisions are particularly useful in identifying customary international law.

Courts may examine:

• State practice;
• opinio juris;
• diplomatic statements;
• national legislation;
• government positions;
• official documents;
• previous judicial decisions.

A judgment itself does not automatically create customary international law.

Instead, it may help determine whether the necessary elements of customary international law already exist.

Judicial Decisions and Treaty Interpretation

International courts frequently interpret treaties.

Their decisions may clarify:

• ordinary meaning of treaty terms;
• context;
• object and purpose;
• subsequent practice;
• supplementary means of interpretation.

Previous judicial interpretations may therefore be persuasive when similar treaty provisions arise in later disputes.

Judicial Decisions and General Principles of Law

Courts may also rely upon previous decisions when identifying or applying general principles of law.

Judicial reasoning has contributed to the development and application of principles such as:

• good faith;
• res judicata;
• estoppel;
• reparation;
• procedural fairness.

However, the judicial decision itself should not automatically be confused with the legal principle being identified.

Important Judicial Decisions

S.S. Lotus Case, 1927

The Permanent Court of International Justice considered questions relating to State jurisdiction and sovereignty.

The case is historically important for understanding the relationship between State sovereignty and international law.

Chorzów Factory Case, 1928

The Permanent Court of International Justice considered the consequences of an internationally wrongful act.

The Court established the principle of full reparation, according to which reparation should, as far as possible, eliminate the consequences of the wrongful act.

The case remains fundamental to the law of State responsibility.

Corfu Channel Case, 1949

The ICJ considered questions concerning State responsibility, sovereignty and evidence.

The case is important for understanding the obligations of States and the role of judicial reasoning in international law.

North Sea Continental Shelf Cases, 1969

The ICJ examined the formation of customary international law.

The case is particularly important for understanding:

• State practice;
• opinio juris;
• the relationship between treaties and custom;
• formation of customary rules.

Barcelona Traction Case, 1970

The ICJ distinguished between obligations owed to particular States and obligations owed to the international community as a whole.

The case contributed significantly to the development of the concept of obligations erga omnes.

Nicaragua v. United States, 1986

The ICJ examined:

• prohibition of force;
• non-intervention;
• self-defence;
• customary international law.

The case demonstrated that customary international law can exist alongside treaty obligations.

Meaning of Juristic Writings

Juristic writings are scholarly works produced by recognised experts in international law.

They include:

• textbooks;
• treatises;
• legal commentaries;
• academic articles;
• research studies;
• expert analyses.

Article 38(1)(d) refers to the teachings of the most highly qualified publicists of the various nations.

Such writings assist courts and practitioners in understanding, organising and interpreting international law.

Role of Juristic Writings

Juristic writings may assist in:

• explaining complex legal principles;
• identifying State practice;
• analysing customary international law;
• interpreting treaties;
• tracing historical development;
• comparing different legal approaches;
• identifying areas of disagreement;
• developing systematic explanations of international law.

They are particularly useful when a legal rule is uncertain or developing.

Highly Qualified Publicists

Article 38(1)(d) does not treat every legal publication as having the same authority.

The usefulness of a juristic work may depend upon:

• expertise of the author;
• quality of research;
• depth of analysis;
• accuracy;
• recognition within the field;
• relevance to the particular legal question.

A highly respected scholarly work may have considerable persuasive value, but it does not become binding law merely because it is influential.

Important Jurists

Several scholars have historically made significant contributions to the study and development of international law.

Hugo Grotius

Grotius is regarded as one of the foundational figures in the development of modern international legal thought.

His writings examined subjects including:

• war;
• peace;
• treaties;
• relations between States;
• law of nations.

Emer de Vattel

Vattel made important contributions to theories of:

• sovereignty;
• equality of States;
• international relations;
• rights and duties of States.

Lassa Oppenheim

Oppenheim’s writings became highly influential in the systematic study of international law.

Hersch Lauterpacht

Lauterpacht contributed significantly to international legal scholarship, particularly concerning:

• judicial settlement;
• international courts;
• human rights;
• sources of international law.

Ian Brownlie

Brownlie’s writings have been widely used in the study of:

• customary international law;
• State responsibility;
• use of force;
• international legal principles.

James Crawford

Crawford made significant contributions to the study of:

• State responsibility;
• Statehood;
• international legal doctrine.

Historical Role of Juristic Writings

Juristic writings played a particularly important role before the development of modern international institutions.

Early jurists attempted to:

• identify rules governing relations between States;
• explain sovereignty;
• regulate warfare;
• analyse treaties;
• systematise the law of nations.

Their writings helped transform international law from a collection of practices and political relationships into a more systematic legal discipline.

Today, treaties, customary international law and institutional practice have a more direct role in establishing legal rules, but juristic writings remain important for interpretation and analysis.

Judicial Decisions vs Juristic Writings

Point	Judicial Decisions	Juristic Writings
Meaning	Decisions of courts and tribunals	Scholarly works of qualified experts
Article 38	Article 38(1)(d)	Article 38(1)(d)
Main function	Determine and interpret legal rules	Explain and analyse legal rules
Binding effect	ICJ judgment binding between parties	Not binding
Authority	Generally highly persuasive	Persuasive depending on expertise
Example	ICJ judgment	International law treatise

Primary Sources vs Subsidiary Means

Primary Sources	Subsidiary Means
Treaties	Judicial decisions
Customary international law	Juristic writings
General principles of law	Used to determine and interpret rules
Establish legal rules according to their legal basis	Do not generally create universally binding rules independently

This distinction is important because judicial decisions and juristic writings are sometimes incorrectly described as independent primary sources of international law.

Importance of Judicial Decisions

Judicial decisions contribute to international law by:

Clarifying Existing Rules

Courts explain the meaning and application of international legal rules.

Identifying Custom

Courts examine State practice and opinio juris to determine whether customary rules exist.

Developing Legal Doctrine

Judgments have contributed to concepts such as:

• obligations erga omnes;
• State responsibility;
• self-defence;
• jurisdiction;
• maritime delimitation.

Promoting Consistency

Previous judgments provide legal reasoning that can guide future courts, States and international lawyers.

Importance of Juristic Writings

Juristic writings contribute by:

• analysing difficult legal questions;
• collecting State practice;
• explaining judicial decisions;
• identifying emerging legal principles;
• comparing competing interpretations;
• providing historical context.

They are especially useful for understanding the development and structure of international law.

Limitations

Judicial Decisions

Judicial decisions:

• are generally binding only within their legally defined scope;
• depend upon the jurisdiction of the relevant court or tribunal;
• must be understood in light of the facts and issues of the particular case;
• do not automatically establish universally binding rules.

Juristic Writings

Juristic writings:

• are not legally binding;
• may contain differing opinions;
• may become outdated;
• may reflect the author’s particular interpretation;
• cannot replace State practice or treaty obligations.

Common Confusions

Are judicial decisions a primary source of international law?

No.

They are a subsidiary means for determining rules of law under Article 38(1)(d).

Are ICJ judgments binding on every State?

No.

Article 59 limits their binding force to the parties and the particular case.

Does the ICJ follow its previous judgments?

It frequently considers them and may follow established reasoning, but it is not generally bound by them as a system of strict stare decisis.

Are juristic writings legally binding?

No.

They are persuasive subsidiary materials.

Can a scholar create a rule of international law by writing about it?

No.

Scholarly opinion may influence legal development and interpretation but does not itself create a binding rule.

Can a national court’s judgment create universal international law?

Not automatically.

A national judgment may provide evidence of State practice or legal opinion, but its significance must be assessed in context.

Are judicial decisions superior to treaties?

No.

Treaties are expressly recognised as a source under Article 38(1)(a), whereas judicial decisions are subsidiary means under Article 38(1)(d).

Relationship with Other Sources

Treaties

Judicial decisions interpret and apply treaties but do not replace the treaty itself.

Custom

Courts help identify customary rules by examining State practice and opinio juris.

General Principles

Judicial decisions can help identify and apply general principles of law.

Juristic Writings

Scholarly writings assist in understanding all of these sources.

Topic at a Glance

Point	Position
Source category	Subsidiary means for determining rules of law
Legal basis	Article 38(1)(d), ICJ Statute
Judicial decisions	Judgments and decisions of courts and tribunals
Juristic writings	Scholarly works of highly qualified publicists
ICJ judgments	Binding between parties under Article 59
General precedent	Not generally binding on all States
Main function	Identification, interpretation and clarification of international law
Custom	Decisions help determine State practice and opinio juris
General principles	Decisions may help identify and apply them
Important cases	Lotus, Chorzów Factory, North Sea Continental Shelf, Nicaragua
Major limitation	Neither category generally creates universally binding rules by itself

Quick Revision

• Judicial decisions and juristic writings are recognised under Article 38(1)(d) of the ICJ Statute.
• They are subsidiary means for determining rules of law.
• Judicial decisions include judgments and decisions of international and national courts and tribunals.
• Juristic writings include scholarly books, articles, commentaries and treatises.
• Article 59 of the ICJ Statute provides that an ICJ judgment is binding between the parties and in respect of the particular case.
• ICJ judgments are therefore not generally binding precedents for all States.
• International courts frequently consider previous decisions because of their persuasive value.
• Judicial decisions can assist in:
  • interpreting treaties;
  • identifying customary international law;
  • applying general principles;
  • clarifying international legal rules.
• Juristic writings help explain and systematise international law.
• The writings of highly qualified publicists may have significant persuasive value but are not binding.
• Chorzów Factory is important for reparation.
• North Sea Continental Shelf is important for State practice and opinio juris.
• Nicaragua v. United States is important for force, intervention and customary law.
• Lotus is historically important for jurisdiction and sovereignty.
• Judicial decisions and juristic writings must be distinguished from the primary sources identified in Article 38(1)(a)–(c).
• Neither judicial decisions nor scholarly writings automatically create universally binding international law.

Conclusion

Judicial decisions and juristic writings occupy an important supporting position within the system of Public International Law. Article 38(1)(d) of the ICJ Statute recognises them as subsidiary means for determining rules of law. Judicial decisions clarify and apply international legal rules, while juristic writings analyse, organise and explain those rules. Although neither category generally operates as an independent primary source of international law, both have played a major role in identifying customary rules, interpreting treaties, developing legal principles and promoting consistency in international legal reasoning.