Chapter 2 (Source of PIL) Notes of Public International Law

 Chapter 2

Sources of PIL

a.       Meaning of Source

Meaning of Sources in Public International Law

Definition of Sources

• The term "sources" of Public International Law (PIL) refers to the origins from which international legal rules derive their authority and validity.
• Malcolm N. Shaw defines a source of PIL as fulfilling two key requirements:
1. Legitimacy – It must be recognized by a legitimate authority.
2. Due Process – It must be established through an accepted law-making process.
• Andrea Bianchi also refers to "sources of PIL" as "international law-making processes," highlighting the procedural aspect of law creation.

Sources vs. Evidence of PIL

• Sources of PIL: These are the origins of legal rules (e.g., treaties, customs).
• Evidence of PIL: These are materials that help determine the existence of a legal rule (e.g., judicial decisions, scholarly writings).

Primary Sources of PIL (ICJ Statute, Article 38(1))

1.      Treaties (International Conventions)

• Formal written agreements between states or international organizations.
• Example: Vienna Convention on the Law of Treaties (VCLT), 1969.

2.      Customary International Law

• Derived from consistent state practice (material element) and a belief that such practice is legally binding (opinio juris).
• Example: Diplomatic immunity, as practiced historically.

3.      General Principles of Law

• Common principles found in most national legal systems.
• Examples: Good faith, estoppel, fairness.

4.      Judicial Decisions & Teachings of Publicists (Subsidiary Sources)

• Courts and tribunals use past rulings and scholarly opinions to interpret and apply international law.
• Example: ICJ rulings in landmark cases like Nicaragua v. USA (1986).

Additional Contemporary Sources

• Jus Cogens (Peremptory Norms): Fundamental principles from which no derogation is permitted (e.g., prohibition of genocide).
• Erga Omnes Obligations: Duties owed to the international community as a whole (e.g., prohibition of slavery).
• Resolutions of International Organizations: May be binding or non-binding depending on their legal basis (e.g., UNGA resolutions as soft law, UNSC resolutions under Chapter VII as binding).
• Unilateral Acts of States: Declarations or commitments by states that may create legal obligations.

Conclusion

The sources of Public International Law establish the framework for global legal order. Treaties, customs, and general principles serve as the primary legal foundations, while judicial decisions, scholarly writings, and resolutions contribute to interpretation and application.

b.      Treaties

Treaties as a Source of Law

1. Concept of Treaties

• Treaties are one of the primary sources of Public International Law (PIL), as recognized under Article 38(1)(a) of the ICJ Statute.
• They are formal written agreements between states or international organizations that create legally binding rights and obligations.
• Treaties are crucial in developing international law, as they codify existing customs or establish new legal rules.

2. Definition of Treaties

• According to Article 2(1)(a) of the Vienna Convention on the Law of Treaties (VCLT), 1969:

"Treaty" means an international agreement concluded between States in written form and governed by international law, whether embodied in a single instrument or in two or more related instruments, and whatever its particular designation."

• The Vienna Convention on the Law of Treaties between States and International Organizations (VCLTIO), 1986, expands this definition to include agreements between states and international organizations or between international organizations.

3. Forms of Treaties

A. Based on Parties Involved

• Bilateral Treaties: Agreements between two states. Example: Nepal-India Friendship Treaty.
• Multilateral Treaties: Agreements between three or more states. Example: Paris Agreement (2015) on climate change.

B. Based on Function in International Law

• Law-Making Treaties: Treaties that create general legal rules applicable to multiple states.
• Example: Universal Declaration of Human Rights (UDHR), 1948 (which later influenced binding human rights treaties).
• Contractual Treaties: Similar to contracts in national law, these establish specific obligations between parties.
• Example: Trade agreements, such as WTO agreements.

4. Treaty-Making Process

A treaty goes through several stages before becoming legally binding:

1. Negotiation – States or organizations discuss the terms.
2. Drafting & Adoption – The final text is prepared.
3. Signature – States express their preliminary agreement.
4. Ratification/Accession – States formally agree to be bound.
5. Entry into Force – The treaty becomes legally binding.

• Ratification vs. Accession:
• Ratification: A state that has signed a treaty officially confirms its consent through its internal legal process.
• Accession: A state that did not sign the treaty at first later agrees to be bound by it.

5. Legal Principles Governing Treaties

A. Pacta Sunt Servanda (VCLT, Article 26)

• This Latin principle means "agreements must be kept."
• Once a treaty is in force, states are legally obligated to uphold its terms in good faith.

B. Jus Cogens and Invalidity of Treaties (VCLT, Article 53)

• A treaty is void if it conflicts with peremptory norms of international law (jus cogens).
• Example: A treaty permitting genocide or torture would be automatically void.
• Case Example: Nicaragua v. USA (1986) – ICJ ruled that the prohibition of force is jus cogens, making violations legally unacceptable.

6. Termination of Treaties

Treaties may be terminated under certain conditions:

• By mutual consent of the parties.
• By material breach (VCLT, Article 60).
• By fundamental change of circumstances (VCLT, Article 62).
• By emergence of a new jus cogens norm (VCLT, Article 64).
• Case Example: Gabcikovo-Nagymaros Case (Hungary v. Slovakia, ICJ, 1997) – Hungary attempted to terminate a treaty based on changed circumstances, but the ICJ ruled that changes must be fundamental and unforeseen.

7. Treaties and Non-Party States

• General Rule (VCLT, Article 34):
• Pacta tertiis nec nocent nec prosunt – Treaties do not create obligations or rights for third parties without their consent.
• Exceptions:
• If a non-party explicitly agrees to be bound (VCLT, Article 35).
• If the treaty reflects customary international law, it makes it binding even on non-parties.

8. Role of Treaties in Public International Law

• Primary source of international law: Treaties provide clarity and predictability in legal relations.
• Codification of customs: Many treaties help convert customary international law into written rules.
• Mechanism for cooperation: States use treaties to address global challenges (e.g., climate change treaties, trade agreements, human rights conventions).
• Binding legal framework: Unlike soft laws (e.g., UNGA resolutions), treaties create legal obligations enforceable under international courts and tribunals.

9. Conclusion

• Treaties are essential instruments in international law, binding parties to agreed-upon rules.
• Governed by VCLT, they ensure legal certainty and cooperation among nations.
• Their legal force depends on ratification, compliance, and their relationship with customary law and jus cogens norms.

c.       Customs

Customs as a Source of Law

1. Concept of Customary International Law

• Customary International Law (CIL) is one of the oldest and most fundamental sources of Public International Law (PIL).
• It consists of long-standing practices of states that are accepted as legally binding.
• Recognized under Article 38(1)(b) of the ICJ Statute, which states:

"International custom, as evidence of a general practice accepted as law."

• Customary law often develops before written agreements (treaties) and serves as a foundation for many international legal principles.

2. Definition of Customary International Law

·         According to Malcolm N. Shaw, CIL consists of:

1. State practice – A consistent and general pattern of behavior by states.
2. Opinio juris – The belief that such practice is legally required.

·         The International Law Commission (ILC) describes CIL as:

"A general practice accepted as law, rather than merely habitual conduct."

3. Elements of Customary International Law

There are two essential elements for a rule to qualify as CIL:

A. State Practice (Material Element)

·         Refers to consistent, uniform, and widespread conduct by states.

·         Does not have to be universal, but must be followed by a majority, especially states directly affected.

·         Forms of State Practice:

• Diplomatic correspondence
• Official government statements
• National legislation
• Judicial decisions
• Military manuals and rules of engagement
• UN resolutions and declarations

·         Case Example: The Asylum Case (Colombia v. Peru, ICJ, 1950)

• Colombia argued that granting diplomatic asylum was a regional customary practice in Latin America.
• ICJ ruled that state practice must be consistent and uniform—the evidence presented was not enough to establish a binding custom.

B. Opinio Juris (Psychological Element)

• States must believe that the practice is legally obligatory, not just done out of habit or convenience.
• Distinguishes legal customs from mere state practices.
• Case Example: The North Sea Continental Shelf Case (Germany v. Denmark & Netherlands, ICJ, 1969)
• ICJ ruled that the "equidistance principle" was not a binding custom because state practice was inconsistent and lacked opinio juris.

4. Evolution and Formation of Customary Law

• CIL does not require a fixed time duration, but should show consistent and widespread practice.
• Special consideration is given to the practice of powerful or directly affected states.
• Example: The rule of diplomatic immunity developed over centuries before being codified in the Vienna Convention on Diplomatic Relations (1961).

5. Customary International Law vs. Treaty Law

Feature	Customary Law	Treaty Law
Form	Unwritten	Written agreement
Binding Nature	Automatically binding	Binding only on ratifying states
Modification	Evolves over time	Requires formal amendments
Application	Universal (unless objected)	Limited to signatory states

 

• Interaction: Some treaties codify customary law (e.g., the Geneva Conventions on the Laws of War), while some customs fill gaps in treaty law.

6. Special Rules Related to Customary Law

A. Persistent Objector Rule

• A state can refuse to be bound by an emerging custom if it has persistently and explicitly objected to it from the beginning.
• Case Example: Fisheries Case (UK v. Norway, ICJ, 1951)
• Norway objected to the "10-mile rule" in maritime boundary law and was not bound by it.

B. Jus Cogens and Customary Law

• Jus Cogens norms (peremptory norms) override customary rules.
• Examples: Prohibition of genocide, slavery, torture, and aggression.
• Case Example: Nicaragua v. USA (ICJ, 1986)
• ICJ ruled that the prohibition of the use of force is a customary norm and a jus cogens rule.

7. Evidence of Customary International Law

• Sources from which state practice and opinio juris can be determined:
• ICJ and PCIJ judgments
• UN resolutions
• Statements by state officials
• National court decisions
• Treaties that reflect customs
• Practices of international organizations

8. Customary Law in International Court Cases

A. The Paquete Habana Case (US Supreme Court, 1900)

• The US Navy seized fishing vessels during the war.
• The court ruled that customary law protects small fishing boats from seizure in war, proving that customs can be legally binding even without treaties.

B. The Lotus Case (France v. Turkey, PCIJ, 1927)

• France argued that only the flag state (France) had jurisdiction over crimes on the high seas.
• PCIJ ruled that no binding customary rule restricted Turkey’s jurisdiction, emphasizing the importance of proving both state practice and opinio juris.

9. Customary Law and Non-State Actors

• Traditionally, CIL applied only to states, but now it also applies to:
• International organizations (e.g., UN, WHO)
• Individuals (e.g., criminal responsibility for war crimes)
• Corporations (e.g., responsibility under international human rights law)

10. Conclusion

• Customary International Law is a primary source of international law, binding on all states unless persistently objected to.
• It evolves through state practice and opinio juris, making it flexible but sometimes difficult to prove.
• It plays a critical role in filling legal gaps, especially where no treaty exists.

d.      General Principles of Law

General Principles of Law as a Source of Law

1. Concept of General Principles of Law

• General Principles of Law (GPL) serve as a foundational source of international law, particularly when treaties and customary law do not provide a clear solution.
• Recognized under Article 38(1)(c) of the ICJ Statute, which states:

"The general principles of law recognized by civilized nations."

• These principles act as gap-fillers, ensuring that courts do not find a case non liquet (a situation where no law exists).

2. Definition of General Principles of Law

• Malcolm N. Shaw defines GPL as:

"Principles common to major legal systems, which can be applied in international law to maintain justice and fairness."

• The International Law Commission (ILC) notes that GPL:
• Serve as a legal compass to guide judicial decisions.
• Are derived from domestic legal systems and international legal principles.

3. Origin of General Principles of Law

GPL originates from two primary sources:

A. General Principles Derived from National Legal Systems

·         Common legal principles found in most domestic laws.

·         Examples:

• Good faith (bona fide) – Acting honestly and fairly in legal agreements.
• Estoppel – A party cannot contradict its previous statements if another party has relied on them.
• Equity and justice – Ensuring fairness in legal decisions.

·         Case Example: Temple of Preah Vihear Case (Cambodia v. Thailand, ICJ, 1962)

• The ICJ applied estoppel, ruling that Thailand could not deny Cambodia's sovereignty over the temple after previously accepting French maps showing it as Cambodian territory.

B. General Principles Derived from International Law

·         Principles that exist independently of national laws but are recognized as fundamental to the international legal system.

·         Examples:

• Sovereign equality of states – All states are equal in international law.
• Exclusive jurisdiction within a state's territory – States have full control over legal matters within their borders.
• Prohibition of abuse of rights – States cannot use their legal rights in a way that harms others unfairly.

·         Case Example: Barcelona Traction Case (Belgium v. Spain, ICJ, 1970)

• The ICJ reaffirmed the principle of legal personality, stating that companies have rights under international law.

4. Role of General Principles in International Law

A. Filling Legal Gaps

• GPL ensures that courts do not fail to deliver justice due to a lack of explicit rules.
• Example: The ICJ and other tribunals rely on the GPL when treaties or customs do not provide direct guidance.

B. Interpreting Existing Laws

• Courts use the GPL to clarify ambiguous provisions in treaties or customary law.
• Case Example: Golder v. UK (ECHR, 1975)
• The European Court of Human Rights applied the principle of access to justice, even though it was not explicitly stated in the treaty.

5. Relationship with Other Sources of Law

Feature	Treaties	Customary Law	General Principles of Law
Binding Force	Only for parties	Universal (unless objected)	Universal
Codification	Written agreements	Unwritten but established	Inferred from legal systems
Function	Creates new rules	Establishes long-standing practices	Fills gaps in law

 

6. Criticism of General Principles of Law

• Vagueness – Some argue that the GPL lacks clear definitions and consistency.
• Civilized Nations Clause – The phrase "recognized by civilized nations" in Article 38(1)(c) is now considered outdated and discriminatory.
• Judicial Discretion – Courts may interpret GPL differently, leading to inconsistent rulings.

7. Conclusion

• General Principles of Law serve as a crucial safety net in international law.
• They ensure justice, fairness, and consistency when other sources do not provide clear guidance.
• Despite criticisms, GPL remains a fundamental part of the legal framework, shaping international jurisprudence.

e.       Judicial Decisions and ICJ Practices

Judicial Decisions and ICJ Practices as a Source of Law

1. Concept of Judicial Decisions as a Source of Law

• Judicial decisions refer to rulings by international and national courts that help in the interpretation, application, and development of international law.
• Recognized under Article 38(1)(d) of the ICJ Statute, which states:

"Subject to the provisions of Article 59, 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."

• Judicial decisions are considered subsidiary sources—they do not create law but help in clarifying and applying existing legal principles.

2. Legal Status of Judicial Decisions in International Law

• Declaratory, not legislative – Unlike treaties and customs, judicial decisions do not create binding law but clarify existing rules.
• Binding only between the parties – As per Article 59 of the ICJ Statute, an ICJ ruling is binding only on the parties to the case and only for that case.
• No formal doctrine of precedent – Unlike common law systems, international law does not follow strict stare decisis (binding precedent). However, courts often consider past judgments as persuasive authority.

3. Role of the ICJ in Developing International Law

The International Court of Justice (ICJ) plays a significant role in shaping international law through its judgments and advisory opinions.

A. ICJ's Function in Resolving Disputes

• The ICJ settles legal disputes between states based on international law.
• It provides authoritative interpretations of treaties, customary international law, and general principles of law.

B. ICJ's Advisory Opinions

• The ICJ also gives advisory opinions on legal questions referred by UN bodies.
• Although not legally binding, advisory opinions influence state practice and treaty interpretations.

Case Example: Legal Consequences of the Construction of a Wall in the Occupied Palestinian Territory (ICJ, 2004)

• The ICJ ruled that Israel’s construction of a wall in the occupied territory violated international law.
• This influenced UN resolutions and shaped global legal debates on self-determination and occupation law.

4. Notable ICJ Cases Influencing International Law

Case	Legal Principle Established
Nicaragua v. USA (1986)	Customary prohibition on the use of force
North Sea Continental Shelf Case (1969)	Elements of customary law formation
Barcelona Traction Case (1970)	Concept of erga omnes obligations
Fisheries Case (1951)	Persistent objector rule in customary law
Genocide Case (Bosnia v. Serbia, 2007)	Responsibility of states for genocide prevention

 

5. Judicial Decisions Beyond the ICJ

Other international courts and tribunals also contribute to international law:

• Permanent Court of Arbitration (PCA) – Settles disputes between states and private parties.
• International Criminal Court (ICC) – Develops international criminal law (e.g., war crimes, genocide).
• International Tribunal for the Law of the Sea (ITLOS) – Resolves maritime disputes.
• Regional courts (e.g., European Court of Human Rights, African Court on Human and Peoples’ Rights).

6. Influence of Judicial Decisions on State Behavior

• Guidance for future disputes – States consider past ICJ rulings in their legal arguments.
• Shaping customary law – Repeated legal reasoning in cases can influence state practice and opinio juris.
• Reference in treaty interpretation – Many treaties incorporate ICJ jurisprudence into their application.

7. Criticism of Judicial Decisions as a Source of Law

• Limited enforcement power – ICJ rulings depend on voluntary compliance by states.
• No binding precedent – Lack of strict stare decisis can lead to inconsistent interpretations.
• Political influence – Some ICJ rulings face criticism for being influenced by political considerations.

8. Conclusion

• Judicial decisions, particularly from the ICJ, serve as authoritative guides in international law.
• Although not primary sources, they help in interpreting, applying, and shaping legal rules.
• The ICJ remains the most influential international tribunal, and its rulings significantly impact state practice and global legal norms.

f.        Resolutions Adopted by International Organizations

Resolutions Adopted by International Organizations as a Source of Law

1. Concept of Resolutions in International Law

• Resolutions are formal decisions or declarations adopted by international organizations, such as the United Nations (UN), World Health Organization (WHO), and other international bodies.
• They can be binding or non-binding, depending on the nature of the organization and the legal authority granted by its charter.
• Article 38(1) of the ICJ Statute does not explicitly mention resolutions as a source of law, but they are often considered subsidiary sources or influential in shaping customary international law.

2. Legal Status of Resolutions

Resolutions can be classified based on their binding nature:

A. Binding Resolutions ("Hard Law")

• Some resolutions are legally binding on member states, particularly those adopted under specific provisions of international treaties or charters.
• Examples:
• United Nations Security Council (UNSC) Resolutions under Chapter VII of the UN Charter (e.g., sanctions, use of force).
• WHO International Health Regulations which require states to report certain disease outbreaks.
• Example: UNSC Resolution 1373 (2001) required all states to take measures against terrorism, making it binding under Article 25 of the UN Charter.

B. Non-Binding Resolutions ("Soft Law")

• Many resolutions serve as recommendations or guidelines rather than enforceable rules.
• These resolutions may influence state behavior, treaty negotiations, and customary law development.
• Examples:
• UN General Assembly (UNGA) Resolutions – Generally non-binding but influential (e.g., UDHR, 1948).
• Declarations by International Conferences – Set global norms but do not impose legal obligations.

3. Role of Resolutions in International Law

A. Influence on Customary International Law

• Resolutions contribute to the formation of customary international law (CIL) by reflecting state practice and opinio juris.
• Example: The Universal Declaration of Human Rights (UDHR, 1948) was initially non-binding but later influenced the development of human rights treaties and customary law.

B. Guiding Treaty Interpretation

• Courts and tribunals use resolutions to interpret and clarify treaty provisions.
• Example: The 1974 UNGA Resolution on the Definition of Aggression has been referenced by the ICJ and ICC in cases related to the use of force.

C. Political and Diplomatic Impact

• Resolutions shape international policies and encourage states to adopt new legal frameworks.
• Example: UNGA resolutions condemning apartheid led to international pressure and the eventual dismantling of South Africa’s apartheid system.

4. Key International Organizations and Their Resolutions

Organization	Resolution Type	Binding Nature	Example
UN Security Council (UNSC)	Chapter VII Resolutions	Binding	UNSC Resolution 678 (1990) authorizing a force against Iraq
UN General Assembly (UNGA)	Recommendations & Declarations	Non-binding	UDHR (1948) influenced human rights law
World Health Organization (WHO)	International Health Regulations	Binding	WHO Pandemic Treaty (under negotiation)
International Labour Organization (ILO)	Conventions & Recommendations	Some binding	ILO Conventions on labor rights
European Union (EU)	Regulations & Directives	Binding on member states	GDPR (2018) on data protection

 

5. Criticism of Resolutions as a Source of Law

• Lack of enforcement – Many resolutions are politically influential but lack legal enforceability.
• Selective compliance – States may choose to ignore non-binding resolutions.
• Vagueness – Some resolutions are broad and open to multiple interpretations.

6. Conclusion

• Resolutions play a crucial role in international law, especially in shaping norms, guiding treaty interpretation, and influencing customary law.
• While binding resolutions (e.g., UNSC decisions) are directly enforceable, non-binding resolutions (e.g., UNGA declarations) influence legal development over time.
• Their significance depends on the organization's mandate, legal framework, and state practice.

 

g.      Other Sources of International Law

Other Sources of International Law

1. Concept of "Other Sources" in International Law

• Public International Law (PIL) is primarily based on treaties, customary law, and general principles of law (Article 38(1) of the ICJ Statute).
• However, modern international law recognizes additional sources that influence legal developments, including:
• Soft law instruments (e.g., UNGA resolutions, declarations).
• Unilateral acts of states (e.g., diplomatic statements, declarations).
• Decisions of international organizations beyond treaties.
• Equity and fairness in international adjudication.

2. Key Additional Sources of International Law

A. Jus Cogens (Peremptory Norms of International Law)

• Definition: Fundamental legal principles that no state may derogate from, even by treaty.
• Examples:
• Prohibition of genocide (ICJ: Bosnia v. Serbia, 2007).
• Prohibition of slavery and torture.
• Prohibition of aggression and crimes against humanity.
• Legal Basis:
• Article 53 of the Vienna Convention on the Law of Treaties (VCLT): A treaty is void if it conflicts with jus cogens.
• ICJ Case Example: Nicaragua v. USA (1986) – Prohibition on the use of force was reaffirmed as a peremptory norm.

B. Erga Omnes Obligations (Duties Owed to the International Community)

• Definition: Obligations that a state owes to all other states, rather than just specific treaty partners.
• Examples:
• Right to self-determination (Barcelona Traction Case, ICJ, 1970).
• Obligations against apartheid and genocide.

C. Soft Law (Non-Binding Legal Instruments)

• Definition: Rules that are not legally binding but influence state behavior and legal developments.
• Examples:
• UN General Assembly Resolutions (e.g., UDHR, 1948).
• Declarations and Guidelines (e.g., Rio Declaration on Environment, 1992).
• International Organization Recommendations (e.g., OECD Guidelines for Multinational Enterprises).
• Significance:
• Soft law can develop into customary law through state practice.
• Helps guide international negotiations and treaty drafting.

D. Unilateral Acts of States

• Definition: Actions or declarations by states that may create legal obligations.
• Examples:
• Declaration of territorial sovereignty (e.g., Norway’s claim in the Fisheries Case, ICJ, 1951).
• Unilateral renunciation of nuclear testing (Nuclear Tests Case, ICJ, 1974 – France’s unilateral declaration created a binding obligation).
• Legal Effect: If a state makes a clear and consistent commitment, it may be legally bound by estoppel.

E. Decisions of International Organizations

• International bodies beyond the UN contribute to international law, including:
• World Trade Organization (WTO) – Trade dispute rulings.
• International Criminal Court (ICC) – Precedents in international criminal law.
• European Union (EU) & African Union (AU) – Binding regulations and directives.
• Legal Impact: While these decisions may not always be binding universally, they shape international legal interpretations and state conduct.

F. Equity and Fairness in International Law

• Courts may apply equitable principles when strict legal rules do not provide a just outcome.
• Example: North Sea Continental Shelf Case (ICJ, 1969) – The ICJ ruled that delimitation of maritime boundaries must consider equitable principles, not just strict legal rules.

3. Significance of These Additional Sources

• Fill gaps in international law when treaties and customs are insufficient.
• Reflect evolving legal norms in human rights, environmental law, and global governance.
• Influence state practice and international court decisions.

4. Conclusion

• Other sources of international law complement traditional sources by adapting to contemporary legal challenges.
• While not all are legally binding, they shape state behavior, influence customary law, and contribute to international legal evolution.