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International & EU Law PART 1 International Law(1).pptx
Summary
# Nature and development of international law
This topic explores the foundational principles and historical evolution of international law, differentiating it from national legal systems and defining core concepts like statehood.
## 1\. Nature and development of international law
International law is a framework of principles and rules that govern international relations, primarily between nation-states. Unlike national law, which operates vertically above individuals, international law functions horizontally among sovereign and equal states.
### 1.1 Distinction between private and public international law
* **Private international law:** This is a part of national law that regulates cases involving foreign elements, such as cross-border disputes regarding applicable law or jurisdiction.
* **Public international law:** This is a distinct body of rules governing international relations between states.
### 1.2 Definition and characteristics of a state
A state, as defined by the Montevideo Convention on the Rights and Duties of States (considered a codification of customary international law), requires four key characteristics to be met:
1. **A stable/permanent population:** A population residing within the state's territory.
2. **Defined territory:** A defined geographical area with recognized boundaries.
3. **Government:** An effective political authority capable of exercising control over the territory and population.
4. **Capacity to enter into relations:** The ability to engage in diplomatic and other relations with other states.
> **Tip:** The Montevideo Convention's emphasis on non-intervention was significant for the development of policies like the U.S. Good Neighbor Policy.
### 1.3 Enforceability of international law
While international law lacks a centralized police force or overarching government, mechanisms for enforcement exist. These include actions and decisions by the UN Security Council, termination of diplomatic relations, and procedures before the International Court of Justice (ICJ). However, compliance largely relies on voluntarism and the consent of states.
### 1.4 Historical development
* **League of Nations (1919):** The first worldwide intergovernmental organization, established to maintain world peace after World War I. It ultimately failed due to the non-participation of key states like the U.S. and the withdrawal of others.
* **United Nations (UN) (1946):** Founded after World War II, it is a universal international organization with its legal basis in the UN Charter. It comprises 193 member states.
#### 1.4.1 Purposes and principles of the UN
The UN's purposes, outlined in Article 1 of its Charter, include:
* Maintaining international peace and security.
* Developing friendly relations among member states.
* Achieving international cooperation in solving international problems.
* Promoting respect for human rights.
* Harmonizing the actions of member states towards common purposes.
Key principles guiding the UN include:
* Recognition of the sovereignty and independence of member states (non-intervention in domestic jurisdiction).
* Equality of member states.
* Compliance with UN Charter obligations in good faith.
* Settlement of disputes by peaceful means.
* Refraining from the threat or use of force.
> **Tip:** Understanding the distinction between intergovernmental and supranational organizations is crucial, especially when comparing the UN to EU law.
### 1.5 Main organs of the UN
The UN has several main organs, including:
* **Security Council:** Responsible for maintaining international peace and security. It can determine threats to peace, breach of peace, or acts of aggression and decide on measures to restore peace. It has 15 members, including five permanent members with veto power. Decisions are binding.
* **General Assembly:** Often called the "Parliament of the UN," it consists of representatives of all member states, with each member having one vote. Its recommendations are generally not binding.
* **International Court of Justice (ICJ):** The principal judicial organ of the UN, successor to the Permanent Court of International Justice. It settles disputes between states and issues advisory opinions. Its judges are elected for nine-year terms.
#### 1.5.1 International Criminal Court (ICC)
It is important not to confuse the ICJ with the International Criminal Court (ICC). The ICC is an intergovernmental organization and tribunal with jurisdiction to prosecute individuals for genocide, crimes against humanity, war crimes, and crimes of aggression. It was established based on the Rome Statute.
> **Example:** The ICC's chief prosecutor's intention to seek arrest warrants in relation to the war in Gaza highlights the ICC's role in prosecuting individuals for international crimes.
#### 1.5.2 Jurisdiction of the ICJ
The ICJ has two main functions:
1. **Advisory opinions:** These are legal opinions issued at the request of the UN Security Council or General Assembly and are not binding.
2. **Resolving disputes between states:** Only states can be parties in disputes brought before the ICJ. Jurisdiction is based on the consent of the states involved, which can be expressed through various means, including compromissory clauses in treaties.
> **Tip:** A "compromissory clause" in a treaty grants jurisdiction to a specific international court (like the ICJ) to resolve disputes arising from that treaty, distinguishing it from an "arbitration clause" where parties choose a college of arbitrators.
### 1.6 Sources of international law
The Statute of the International Court of Justice (Article 38) provides the primary reference for the sources of international law:
1. **International conventions (Treaties):** Written agreements between states governed by international law. The Vienna Convention on the Law of Treaties (1969) provides comprehensive rules for their definition, drafting, amendment, termination, and interpretation.
* **Definition of a treaty:** A written agreement between states subject to international law, stipulating their consent to create, alter, or terminate rights and obligations. The Vienna Convention does not apply to oral agreements or agreements involving international organizations.
* **Binding force:** Treaties are binding and must be performed in good faith, reflecting the principle of \_pacta sunt servanda.
* **Making a treaty:** States express consent to be bound through representatives who must produce "full powers." National legislation determines when a state is officially bound (e.g., after ratification).
* **Reservations:** States may make reservations to exclude or limit the legal effect of certain provisions of a treaty.
* **Entry into force:** Treaties specify their entry into force. If not specified, it generally occurs once consent to be bound is established.
* **Termination/suspension:** Treaties can be terminated or suspended if the treaty provides for it, with the consent of all parties, due to a material breach, or a fundamental change of circumstances (\_rebus sic stantibus), under strict conditions.
* **Dispute settlement:** Disputes can be resolved through negotiation, conciliation, mediation, or referral to the ICJ or arbitration.
2. **Customary international law:** Developed through consistent and general state practice coupled with the psychological element of \_opinio juris sive necessitatis (a belief that the practice is legally obligatory).
* **State practice:** Observable, general, repeated, consistent, and uniform behavior by a significant number of states. Examples include administrative acts, legislation, court decisions, diplomatic declarations, and treaties.
* **Examples of customary international law:** \_Pacta sunt servanda, diplomatic immunity, prohibition on the use of force, and non-refoulement.
3. **General principles of law:** Principles common to most legal systems, such as the principle of obligation to repair damages caused by violations and the principle of good faith in fulfilling treaty obligations.
4. **Subsidiary means:** Judicial decisions and legal doctrine are used to help determine the rules of law but are not binding sources themselves.
#### 1.6.1 Hierarchy of sources
While Article 38 of the ICJ Statute lists sources, there isn't a strict hierarchy, but certain principles apply:
* \_Lex posterior derogat legi priori: A later treaty or agreement prevails over an earlier one.
* \_Lex specialis derogat legi generali: Specific treaty rules (lex specialis) prevail over general rules.
However, \_jus cogens (peremptory norms of general international law) override all other sources. These are fundamental, universally accepted principles from which no derogation is permitted, such as prohibitions against genocide, slavery, and torture.
### 1.7 Relationship between national and international law
Two main approaches exist:
* **Dualism:** International and national law are separate systems with no effect on each other.
* **Monism:** A unitary view where international law prevails over national law (applicable in Belgium).
### 1.8 Subjects of international law
The primary subjects of international law are states, possessing the four characteristics of statehood and sovereignty. Other entities may also be considered subjects depending on the context. Areas like the high seas, outer space, and Antarctica are considered \_res communis (common to all states), while \_terra nullius refers to "nobody's land" open to appropriation.
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# The United Nations and its organs
This section summarizes the establishment, purposes, principles, and main organs of the United Nations, with a particular focus on the Security Council and the General Assembly.
### 2.1 Establishment and purposes of the UN
The United Nations (UN) is an international organization founded after the Second World War in 1946. Its legal basis is the multilateral treaty known as the Charter of the UN, which outlines the rights and obligations of its signatory parties. Today, the UN comprises 193 sovereign states.
The primary purposes of the UN, as outlined in Article 1 of its Charter, are:
* **Maintenance of international peace and security:** This is the cornerstone of the UN's mission.
* **Development of friendly relations between member states:** Fostering cooperation and understanding.
* **Achievement of international cooperation in solving international problems:** Addressing global challenges through collective action.
* **Promotion of respect for human rights:** Upholding fundamental human rights for all.
* **Harmonization of the actions of member states in the achievement of these common purposes:** Serving as a central forum for coordinating international efforts.
### 2.2 Principles of the UN
The UN operates according to a set of fundamental principles enshrined in its Charter, which guide the achievement of its purposes:
* **Sovereign equality of member states:** All member states are equal, regardless of their size or power.
* **Compliance with obligations under the UN Charter in good faith:** States must adhere to their commitments faithfully.
* **Settlement of disputes by peaceful means:** Member states are obligated to resolve their conflicts without resorting to force.
* **Refraining from the threat or use of force:** Member states shall not engage in actions that violate the territorial integrity or political independence of any other state.
* **Non-intervention in domestic affairs:** The UN Charter does not permit UN organs to intervene in matters that fall within the domestic jurisdiction of member states, recognizing their sovereignty.
### 2.3 Main organs of the UN
The UN has several principal organs, each with distinct roles and responsibilities. The three most prominent are:
#### 2.3.1 The Security Council
The Security Council is the main organ of the UN with the primary responsibility for the maintenance of international peace and security. Its key functions include:
* **Peaceful settlement of disputes:** Determining the existence of any threat to peace, breach of peace, or act of aggression, and making recommendations for peaceful resolution. Parties to a dispute are first called upon to seek solutions through negotiation, mediation, arbitration, or other peaceful means.
* **Enforcement actions:** Deciding on measures to maintain or restore international peace and security when peaceful means are insufficient. These measures can range from economic sanctions to military intervention.
**Structure and Voting:**
* The Security Council has 15 members: 5 permanent members and 10 non-permanent members.
* **Permanent Members:** China, France, Russia, the United Kingdom, and the United States.
* **Non-Permanent Members:** Elected by the General Assembly for two-year terms.
* **Veto Power:** Each permanent member possesses a veto power, meaning that a negative vote from any permanent member on a substantive issue can prevent a resolution from being adopted.
* **Decision-making:** Decisions on substantive matters require an affirmative vote of at least nine members, including the concurring votes of all five permanent members. Procedural matters are decided by an affirmative vote of at least nine members.
* **Abstentions:** Abstentions by permanent members are generally not considered a veto, allowing decisions to be made even if a permanent member abstains.
* **Binding Resolutions:** Resolutions adopted by the Security Council under the UN Charter are binding on all member states.
#### 2.3.2 The General Assembly
The General Assembly is often referred to as the "Parliament of the UN" and consists of representatives from all member states.
* **Composition:** All 193 member states are represented.
* **Voting:** Each member state has one vote.
* **Recommendations:** Decisions and recommendations of the General Assembly are generally not binding, but they carry significant political and moral weight.
* **Matters of Decision:** The General Assembly votes on a wide range of issues, including the UN budget, the election of non-permanent members of the Security Council, and the appointment of the Secretary-General.
#### 2.3.3 Other Important Organs
While the Security Council and General Assembly are central, other significant organs include:
* **Economic and Social Council (ECOSOC):** Focuses on economic, social, and environmental issues.
* **UN Secretariat:** Headed by the Secretary-General, this body comprises the UN's administrative staff and provides support for the organization's work. The Secretary-General is appointed by the General Assembly upon the recommendation of the Security Council.
### 2.4 The International Court of Justice (ICJ)
The International Court of Justice (ICJ) is the principal judicial organ of the UN, succeeding the Permanent Court of International Justice under the League of Nations. It was established in 1946.
* **Composition:** Composed of 15 independent judges elected for nine-year terms by the General Assembly and the Security Council.
* **Statute:** The Statute of the Court is an annex to the UN Charter.
* **Jurisdiction:** The ICJ has two main types of jurisdiction:
* **Advisory Opinions:** It can provide non-binding legal advice on questions referred to it by authorized UN organs, such as the General Assembly and the Security Council.
* **Resolving Disputes between States:** This is its contentious jurisdiction. Critically, **only states can be parties** in contentious cases before the ICJ. The Court's jurisdiction over a state is based on its **consent**. This consent can be expressed through:
* **Special agreement:** States can agree to submit a specific dispute to the ICJ.
* **Compromissory clause:** An international treaty may contain a clause granting jurisdiction to the ICJ for disputes arising from its interpretation or application.
* **Optional clause declarations:** States may unilaterally declare that they accept the compulsory jurisdiction of the ICJ in relation to any other state that makes a similar declaration.
* **Distinction from the ICC:** It is crucial not to confuse the ICJ with the International Criminal Court (ICC). The ICJ settles disputes between states, while the ICC prosecutes individuals for international crimes like genocide, war crimes, and crimes against humanity.
* **Decisions:** ICJ judgments are final and binding on the parties to the dispute and are not open to appeal. If a state fails to comply with a judgment, the other party may have recourse to the Security Council.
### 2.5 Sources of International Law
The Statute of the International Court of Justice, in Article 38, provides a foundational list of the sources of international law that the Court applies:
1. **International conventions (treaties):** Written agreements between states that create legal obligations. The Vienna Convention on the Law of Treaties (1969) is a key instrument governing treaties.
* **Definition of a treaty:** An international agreement concluded between states in written form and governed by international law.
* **Binding force:** Treaties are binding and must be performed in good faith (pacta sunt servanda).
* **Reservations:** States may make reservations to exclude or limit the legal effect of certain treaty provisions.
* **Entry into force:** Treaties typically specify their own entry into force conditions, often upon deposit of a certain number of ratifications.
* **Termination/Suspension:** Treaties can be terminated or suspended under specific conditions, such as by provision in the treaty, consent of parties, material breach, or a fundamental change of circumstances (rebus sic stantibus).
* **Treaty registration:** Treaties concluded by UN member states are registered with the UN Secretariat and published.
2. **Customary international law:** Rules derived from the consistent practice of states, coupled with a belief that such practice is legally obligatory (opinio juris sive necessitatis).
* **State practice:** Must be general, consistent, and uniform. Examples include administrative acts, legislation, court decisions, diplomatic declarations, and treaties.
* **Opinio juris:** The belief that the practice is required by law.
3. **General principles of law:** Fundamental legal principles common to the domestic legal systems of most states. Examples include the principle that every violation of an engagement entails an obligation to repair damages, res judicata (a matter already judged), and compliance with obligations in good faith.
4. **Subsidiary means:**
* **Judicial decisions:** Decisions of international and national courts, which are binding on the parties involved in that specific dispute.
* **Legal doctrine:** Writings of eminent legal scholars, which are not binding but can help in interpreting the law.
#### 2.5.1 Hierarchy of Sources
While Article 38 of the ICJ Statute lists the sources, there is a general hierarchy:
* **Jus Cogens:** Peremptory norms of general international law that cannot be derogated from (e.g., prohibition of genocide, torture, slavery). These norms override all other sources, including treaties and customary law.
* **Treaties and Customary International Law:** Generally considered to be of equal standing, with specific rules for their interaction.
* \_Lex posterior derogat legi priori: A later law repeals an earlier one.
* \_Lex specialis derogat legi generali: A more specific law prevails over a general law between the same parties.
### 2.6 Distinction between Treaties and Customary International Law
> **Tip:** While treaties are written and codified, customary international law evolves organically through state practice and belief. Both are vital sources of international law, and many rules exist in both forms.
### 2.7 The UN Security Council's Enforcement Measures
In cases of threats to peace, breaches of peace, or acts of aggression, the Security Council can take enforcement measures under Chapter VII of the UN Charter. These measures can include:
* **Measures not involving the use of armed force:** Such as imposing economic sanctions, arms embargoes, travel bans, and severing diplomatic relations (Article 41).
* **Measures involving the use of armed force:** If non-forcible measures are inadequate, the Security Council may authorize the use of air, sea, or land forces as may be necessary to maintain or restore international peace and security (Article 42). This can involve blockades or military operations by member states.
### 2.8 Recognition of Palestine
The issue of recognizing Palestine as a state is a significant contemporary development, with numerous UN member states (as of September 2025) having extended such recognition. This process involves the UN General Assembly and is often influenced by historical and political contexts, including past mandate territories.
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# The International Court of Justice (ICJ)
The International Court of Justice (ICJ) serves as the principal judicial organ of the United Nations, tasked with resolving legal disputes between states.
### 3.1 Role and historical context
The ICJ is the successor to the Permanent Court of International Justice, which was established under the League of Nations in 1919. The ICJ itself was set up in 1946 and operates under a Statute that is an annex to the UN Charter. It is important to distinguish the ICJ from the International Criminal Court (ICC). While the ICC prosecutes individuals for international crimes, the ICJ's jurisdiction is limited to settling disputes between states.
### 3.2 Composition of the court
The ICJ comprises independent judges, who are elected for a term of nine years.
### 3.3 Jurisdiction of the ICJ
The ICJ has two primary types of jurisdiction:
#### 3.3.1 Advisory opinions
The ICJ can provide advisory opinions on legal questions. These opinions are not binding but are issued at the request of the UN Security Council or the General Assembly.
#### 3.3.2 Resolving disputes between states
The core function of the ICJ is to adjudicate disputes between states. Only states can be parties to proceedings before the ICJ. The Court's jurisdiction in contentious cases is based on the consent of the states involved.
> **Tip:** Consent to the ICJ's jurisdiction can be expressed in several ways, including by referring a case to the Court by agreement of the parties or through specific provisions within international treaties.
##### 3.3.2.1 Basis of jurisdiction: Consent
The fundamental principle governing the ICJ's jurisdiction is the consent of the states involved. A state must explicitly accept the Court's jurisdiction for it to be legally bound by its decisions.
##### 3.3.2.2 Compromissory clauses
Many international treaties contain a "compromissory clause," which is a provision that grants jurisdiction to a specific international court, such as the ICJ, to resolve disputes arising from the treaty's interpretation or application. This means that states signing such a treaty agree in advance to submit potential future disagreements related to that treaty to the designated court.
> **Example:** The Genocide Convention of 1948 contains a compromissory clause, allowing parties to refer disputes concerning the interpretation or application of the convention to the ICJ.
It is crucial to differentiate a compromissory clause from an arbitration clause. An arbitration clause refers disputes to a college of arbitrators, whose proceedings are typically more flexible and often faster, whereas a compromissory clause designates an existing tribunal or court.
##### 3.3.2.3 Jurisdiction based on optional declarations
States may also make optional declarations accepting the Court's jurisdiction \_ipso facto and without special agreement, in relation to any other state accepting the same obligation.
### 3.4 Application of international law by the ICJ
When deliberating cases, the ICJ applies international law, which includes:
* **International conventions (treaties):** Written agreements between states.
* **International customs:** Established state practice recognized as law.
* **General principles of international law:** Principles common to major legal systems.
* **Subsidiary means:** Judicial decisions and legal scholarship, used to help determine the rules of law.
### 3.5 Decisions of the ICJ
The ICJ's decisions in contentious cases are binding on the parties involved. These judgments are final and not open to appeal.
* **Declaratory judgments:** The Court may issue judgments declaring that one party has breached international law.
* **Reparation:** If a breach is found, the Court can order reparation, typically in the form of financial compensation for losses and damages.
* **Compliance:** If a state fails to comply with a judgment, the other party may have recourse to the UN Security Council.
> **Tip:** ICJ judgments are considered first instance decisions, meaning there is no higher court of appeal available.
### 3.6 Sources of international law as per Article 38 of the ICJ Statute
Article 38 of the Statute of the ICJ outlines the sources of international law that the Court applies:
1. **Treaties or international conventions:** Bilateral or multilateral agreements between states covering various aspects of international relations, such as ending wars, territorial disputes, alliances, and the establishment of international organizations. The **Vienna Convention on the Law of Treaties (1969)** provides key guidelines for the definition, drafting, amendment, termination, and interpretation of treaties.
2. **Customary international law:** This arises from the consistent and general practice of states ("state practice") coupled with the belief that this practice is legally obligatory (\_opinio juris sive necessitatis). Examples include principles like \_pacta sunt servanda (agreements must be kept), \_rebus sic stantibus (fundamental change of circumstances), diplomatic immunity, the prohibition on the use of force, and \_non-refoulement.
3. **General principles of law:** These are fundamental principles recognized across most national legal systems, such as the obligation to repair damages caused by a violation, \_res judicata (a matter already judged), and the principle of good faith in fulfilling treaty obligations.
4. **Subsidiary means:** Judicial decisions and the writings of legal scholars can be used to help identify and interpret the rules of international law.
#### 3.6.1 Hierarchy of sources
While Article 38 lists these sources, there is an implicit hierarchy. Generally, later treaties prevail over earlier ones (\_lex posterior derogat legi priori), and specific rules prevail over general ones (\_lex specialis derogat legi generali). However, peremptory norms of international law (\_jus cogens)—fundamental principles that cannot be derogated from, such as prohibitions against genocide, slavery, and torture—override all other norms, whether treaty-based or customary.
#### 3.6.2 Treaties as a source of law
Treaties are a crucial source of international law. The Vienna Convention on the Law of Treaties defines a treaty as a written agreement between states governed by international law. Key aspects regulated by the Convention include the definition of a treaty, the principle of \_pacta sunt servanda, how states express consent to be bound (e.g., through ratification), the possibility of reservations, treaty entry into force, and grounds for termination or suspension (e.g., material breach or fundamental change of circumstances). Treaties are registered with the UN Secretariat and published.
> **Example:** The North Atlantic Treaty Organization (NATO) is an alliance established by treaty, with Article 5 stipulating collective defense.
#### 3.6.3 Customary international law
Customary international law requires two elements:
* **Material element:** Consistent and uniform state practice.
* **Psychological element:** \_Opinio juris sive necessitatis—a belief that the practice is legally binding.
State practice can be evidenced through administrative acts, legislation, court decisions, diplomatic declarations, and treaties.
#### 3.6.4 General principles of law
These principles ensure consistency and fairness in international legal proceedings, drawing from commonalities in national legal systems.
#### 3.6.5 Dispute settlement under treaties
Treaties themselves may provide mechanisms for dispute settlement, potentially involving the ICJ, arbitration, or referral to the UN Security Council in cases impacting international peace and security.
### 3.7 Relationship between international and national law
Two main approaches exist regarding the relationship between international and national law:
* **Dualism:** Views international and national law as separate systems, with international law not automatically applying within a state's domestic legal order.
* **Monism:** Considers international and national law as part of a single, unified legal system. In monist states, international law generally prevails over national law. Belgium follows a monist approach.
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# Sources of international law
This section outlines the primary sources of international law, their hierarchy, and the means by which their existence and content can be determined.
## 4\. Sources of international law
The primary sources of international law are codified in Article 38 of the Statute of the International Court of Justice (ICJ). These sources provide the legal foundation upon which international legal disputes are resolved and international relations are governed.
### 4.1 Treaties or international conventions
Treaties are formal written agreements between states that are governed by international law. They play a crucial role in various aspects of international relations, including:
* The termination of wars.
* The acquisition of territory.
* The settlement of disputes between states.
* The establishment of alliances.
* The creation of international organizations.
#### 4.1.1 The Vienna Convention on the Law of Treaties (VCLT), 1969
The VCLT, often referred to as the "treaty on treaties," establishes comprehensive guidelines for the definition, drafting, amendment, termination, and interpretation of treaties.
* **Definition:** An "international treaty" is a written agreement between states subject to international law that stipulates their consent to the creation, alteration, or termination of their rights and obligations. The VCLT primarily applies to written agreements, though oral agreements can still have legal effect.
* **Binding Force:** Treaties are binding and must be performed in good faith. This principle is encapsulated by the Latin phrase "pacta sunt servanda," meaning "agreements must be kept."
* **Parties to a Treaty:** States are the primary parties to treaties. However, states are represented by individuals who must possess "full powers" – a document demonstrating their authority to represent the state in treaty negotiations and to express the state's consent.
* **Consent:** Expressing consent to be bound by a treaty is a vital element. This can occur through various means, as outlined in Articles 12-15 of the VCLT, including signature, ratification, acceptance, or accession. The specific internal legislation of a state determines when it is officially bound by a treaty, often requiring ratification after internal approval.
* **Reservations:** States may make reservations when consenting to a treaty, which allows them to exclude or limit the legal effect of certain provisions.
* **Entry into Force:** Treaties typically specify their own entry into force. If not, they enter into force once all parties have consented to be bound. Many treaties also specify a date or a period following the last ratification for their entry into force. Treaties signed by UN members are registered with the UN Secretariat and published.
* **Termination, Suspension, or Withdrawal:** A treaty can be terminated, suspended, or withdrawn from under several circumstances:
* If the treaty itself provides for it, or with the consent of all parties.
* In the event of a material breach of the treaty by one of the parties, meaning a violation of a provision essential to the treaty's object and purpose.
* Due to a fundamental change of circumstances ("rebus sic stantibus"), provided that the circumstances were essential to the treaty's obligations and the change has had a radical effect on those obligations. This is a strict condition and requires unanimous agreement among parties.
* **Dispute Settlement:** Disputes arising from treaty interpretation or application can be settled through various means, including referral to the ICJ, arbitration, or intervention by the UN Security Council if international peace and security are at stake.
> **Tip:** Remember that while the VCLT primarily governs treaties between states, other international agreements (e.g., between states and international organizations) also exist and have legal effects, even if not written.
### 4.2 Customary international law
Customary international law (CIL) develops from consistent and general state practice that is accepted as legally binding. It is a dynamic source of law, evolving with societal changes, in contrast to the written nature of treaties. CIL is characterized by two essential elements:
* **Material Element (State Practice):** This refers to the observable behavior of states. It must be general, repeated, consistent, uniform, and common to a significant number of states. Examples of state practice include administrative acts, legislation, court decisions, diplomatic declarations, and treaty provisions.
* **Psychological Element (Opinio Juris Sive Necessitatis):** This is the belief that the state's behavior is motivated by a sense of legal obligation or necessity, rather than mere comity or policy. States act in a certain way because they believe they are legally bound to do so.
Key principles that have evolved into customary international law include:
* "Pacta sunt servanda."
* "Rebus sic stantibus."
* Diplomatic immunity.
* The prohibition on the use of force.
* The principle of non-refoulement for refugees.
### 4.3 General principles of law
These are fundamental legal principles that are common to the major legal systems of the world. They serve to fill gaps where treaties or customary law may not provide a clear rule. Examples include:
* The principle that every violation of an engagement entails an obligation to repair the damage caused.
* \_Res judicata: the principle that a judgment rendered by a judicial body is binding on the parties involved in that dispute.
* Compliance with obligations contained in treaties in good faith ("goede trouw" / "bonne foi").
### 4.4 Subsidiary means
These are not direct sources of international law but are used to help determine the content of the law.
* **Judicial decisions:** Decisions of international and national courts can clarify and confirm existing rules of international law. However, they are only binding on the parties to the specific dispute (\_res judicata).
* **Legal doctrine:** Writings of respected legal scholars can provide valuable insights and interpretations of international law, though they are not legally binding in themselves.
### 4.5 Hierarchy or "ranking" of the sources
Article 38 of the ICJ Statute provides a framework for the hierarchy of these sources. While not a strict hierarchy, it indicates a general order of application:
1. **Treaties or international agreements.**
2. **Customary international law.**
3. **General principles of law.**
4. **Subsidiary means:** judicial decisions and legal doctrine.
Within treaties and customary international law, certain principles guide their application when conflicts arise:
* **Lex posterior derogat legi priori:** A later treaty or customary rule prevails over an earlier one.
* **Lex specialis derogat legi generali:** Specific rules (treaty rules as \_lex specialis) prevail over general rules of treaties or customary international law between the same states.
#### 4.5.1 Jus cogens
A critical exception to the above principles relates to \_jus cogens (compelling law) or peremptory norms of general international law. These are fundamental, universally accepted principles that cannot be derogated from by any state, regardless of whether they have explicitly agreed to them. They are considered so essential to the international legal order that they are non-derogable.
* **Examples:** Prohibitions against genocide, slavery, torture, piracy, and the unlawful use of force (except in self-defense).
* **Impact on Hierarchy:** Rules of \_jus cogens override any conflicting treaty provisions or customary international law.
> **Example:** If a treaty were to permit torture, it would be void \_ab initio because torture is prohibited by \_jus cogens.
> **Tip:** Understanding \_jus cogens is crucial for recognizing the absolute prohibitions within international law. It represents the highest level of legal obligation in the international system.
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# International law versus national law and subjects of international law
This section explores the relationship between international law and national law, contrasting their theoretical underpinnings and examining the primary subjects recognized by international law, with a particular focus on the characteristics of states.
## 5\. International versus national law and subjects of international law
### 5.1 The relationship between international and national law
International law and national law represent distinct legal systems that govern different spheres of human interaction. While national law operates within the vertical structure of a state, regulating individuals and domestic institutions, international law functions in a horizontal plane, governing the relations between sovereign states. The interplay and hierarchical relationship between these two legal orders have been a subject of significant debate, leading to two dominant theoretical approaches: dualism and monism.
#### 5.1.1 Dualist approach
The dualist perspective posits that international law and national law are two entirely separate and independent legal systems. According to this view, neither system can directly influence or create norms within the other. International courts are responsible for applying international law, while national courts apply national law. For international law to have an effect within a state's domestic legal order, it must be formally incorporated or transformed into national law through specific legislative acts.
#### 5.1.2 Monist approach
In contrast, the monist approach, which is applicable in Belgium, advocates for a unitary view of legal systems. This perspective suggests that international law and national law are part of a single, overarching legal order. In cases of conflict between the two, international law is generally considered to prevail over national law. This means that international legal norms can have direct application and binding force within a state's domestic legal system without requiring explicit national legislation for their incorporation.
### 5.2 Subjects of international law
Subjects of international law are entities that possess international legal personality, meaning they have rights and obligations under international law and the capacity to bring claims or be held responsible for breaches of international law. While the primary subjects have traditionally been states, the scope has expanded to include international organizations and, to a limited extent, individuals.
#### 5.2.1 States
States are the principal subjects of international law, and their statehood is defined by specific criteria that must be met. These criteria, largely codified in the Montevideo Convention on the Rights and Duties of States, include:
* **A stable/permanent population:** A community of people residing within the state's territory.
* **Defined territory:** A specific geographical area with recognized boundaries.
* **Government:** An effective political authority capable of exercising control over the territory and its population.
* **Capacity to enter into relations with other states:** The ability to engage in diplomatic and other international interactions independently.
##### 5.2.1.1 Sovereignty and independence
A crucial element of statehood is sovereignty, which implies the independence of the state and the superiority of its governmental institutions over its population and territory. As a legal person, a sovereign state possesses the capacity to enter into international relations. The territory of a state is considered inviolable, and respect for its territorial integrity is a cornerstone of international law.
##### 5.2.1.2 Concepts related to territory
* **Res communis:** These are areas or resources not subject to the sovereignty of any single state, available for the use of all states. Examples include the high seas, outer space, and Antarctica. No state can claim exclusive sovereignty over such areas, which are accessible to all for peaceful purposes.
* **Terra nullius:** This term refers to "nobody's land," meaning territory not under the sovereignty of any state and thus open to appropriation. Historically, some inhabited territories were wrongly classified as terra nullius, leading to colonization.
> **Tip:** Understanding the characteristics of a state is fundamental to grasping the foundations of international law, as states are the primary creators and enforcers of its norms.
#### 5.2.2 Other subjects of international law
While states are the main subjects, international organizations, created by states through treaties, also possess international legal personality and are subjects of international law. In certain contexts, such as international criminal law, individuals can also be considered subjects of international law, bearing direct responsibility for international crimes.
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## Common mistakes to avoid
* Review all topics thoroughly before exams
* Pay attention to formulas and key definitions
* Practice with examples provided in each section
* Don't memorize without understanding the underlying concepts
Glossary
| Term | Definition |
|------|------------|
| Public international law | A distinct legal system that governs the relations between sovereign states. |
| Private international law | A set of rules within national law that governs private legal cases involving foreign elements, determining the applicable legal system and competent court. |
| State | An entity characterized by a stable population, a defined territory, an effective government, and the capacity to enter into international relations. |
| Montevideo Convention on the Rights and Duties of States | A treaty signed in 1933 that codified the criteria for statehood under international law, widely considered a reflection of customary international law. |
| United Nations (UN) | An international organization founded in 1946 after World War II, aiming to maintain international peace and security, develop friendly relations among nations, and achieve international cooperation. |
| Security Council | The principal organ of the UN responsible for maintaining international peace and security, with the power to determine threats to peace, breaches of peace, and acts of aggression, and to take measures accordingly. |
| General Assembly | The main deliberative organ of the UN, where all member states are represented and have one vote, making recommendations on a wide range of issues. |
| International Court of Justice (ICJ) | The principal judicial organ of the UN, established in 1946, responsible for settling legal disputes submitted to it by states in accordance with international law. |
| Statute of the International Court of Justice | The legal document that forms an integral part of the UN Charter and governs the composition, jurisdiction, and functioning of the ICJ. |
| Treaties | Formal written agreements between states, governed by international law, that establish rights and obligations for the parties involved. |
| Customary international law | A body of unwritten rules derived from the consistent practice of states that is accepted as legally binding. It comprises a material element (state practice) and a psychological element (opinio juris sive necessitatis). |
| Opinio juris sive necessitatis | The belief by a state that a particular practice is required by law or is a legal necessity, forming the psychological element of customary international law. |
| General principles of law | Fundamental legal principles common to most national legal systems that can be applied in international law. |
| Subsidiary means | Sources that aid in the interpretation and application of international law, including judicial decisions and legal scholarship. |
| Vienna Convention on the Law of Treaties (VCLT) | An international agreement that codifies the rules governing treaties between states, defining what constitutes a treaty, how they are made, interpreted, amended, and terminated. |
| Pacta sunt servanda | A fundamental principle of international law, meaning that agreements must be kept and are binding upon the parties. |
| Rebus sic stantibus | A legal doctrine allowing for the termination or suspension of a treaty due to a fundamental change of circumstances that existed at the time of its conclusion, provided certain strict conditions are met. |
| Jus cogens | Peremptory norms of general international law that are universally accepted and binding on all states, from which no derogation is permitted. Examples include prohibitions against genocide, slavery, and torture. |
| Dualism | An approach to the relationship between international and national law, positing that they are two separate and distinct legal systems that do not directly affect each other. |
| Monism | An approach to the relationship between international and national law, viewing them as part of a single, unified legal system, where international law generally prevails over national law. |
| Sovereignty | The supreme authority of a state within its territory, implying independence from external control and the capacity to engage in international relations. |
| Res communis | Areas or resources that are not subject to the sovereignty of any single state and are available for use by all states, such as the high seas and outer space. |
| Terra nullius | Historically, territory that was considered "nobody's land" and was open to appropriation by a state. |