Public International Law
1. Subjects of International Law
States and Compliance
Hobbes’ "State of Nature": Without law, there is chaos, a "war of all against all" (anarchy).
However, IL does not exist solely to prevent anarchy. It exists because:
1. It creates a structured system of valid legal arguments, obligations, and rights.
- IL provides a common legal language and framework for how states interact,
make claims, and resolve disputes.
- Without this structure, arguments would be inconsistent, opportunistic, and
unpredictable.
- States know what to expect from others and how to justify their actions; this
promotes stability and credibility.
- Example: When Palestine brings a claim to the ICC, it must follow proper
legal procedure (e.g., Art. 12 Rome Statute) and argue within IL frameworks,
not just political narratives.
2. It enables third-party adjudication and accountability.
- IL allows disputes to be handled by neutral bodies (e.g., ICJ, ICC) instead of
devolving into retaliation or force.
- Third-party adjudicators help apply the law objectively, ensuring fairness even
when power is unequal.
- This reduces reliance on power politics and enables smaller or weaker states
to seek justice.
- Example: The ICC’s investigation into alleged war crimes in Palestine enables
a legal forum to assess the conduct of powerful actors like Israel, without
requiring Palestine to resort to political or military means.
3. Unlike international relations (IR), which is based on power politics, IL is grounded in
legal rules and principles.
- IR allows states to act based on interest, strategy, and influence, but IL
imposes normative constraints based on agreed-upon rules.
- Legal rules reduce arbitrariness and encourage consistency, especially in
sensitive matters like sovereignty, war, or recognition.
- This enables long-term cooperation, predictability, and norm development.
- Example: The Montevideo criteria provide a legal, not political, basis for
evaluating statehood, even if a state is not powerful or widely recognized.
International Society of States: A Classical Perspective
- Key Characteristics:
- Universal: Includes nearly all existing states.
- Heterogeneous: Diverse cultures, values, and systems.
- Decentralized: No central authority; law depends on state consent.
- Interdependent: States rely on each other for resources, security, and trade.
, - Example: Berlin Conference (1884-85), Colonial partitioning of Africa
showed how international society operated in practice.
- This concept remains relevant despite the evolution of IL because the core features
of the international society of states (sovereign equality, decentralization, and state
consent) still form the foundation of modern IL.
- Even with the rise of human rights, IOs, and NSAs, states remain the primary
legal subjects, and most legal obligations still depend on their consent (e.g.,
treaties, recognition).
- Thus, understanding IL through the lens of a state-based, decentralized
system is still essential for explaining how IL operates in practice.
International Community (Post-Cold War, European Perspective)
- More recent, post-decolonization development.
- Key Characteristics:
- Organized and rule-based.
- Decolonized: Right to self-determination emphasized.
- Humanization of IL:
- Emergence of Human Rights Law, International Criminal Law,
Environmental Law, Law of the Sea, Law of Common Heritage, rights
for future generations, etc.
- Shared values, solidarity, and cooperation among states while preserving
sovereignty.
- Emphasis on individuals and non-state actors (NSAs) as part of the IL system.
- European teaching of IL reflects these values more than in other regions.
Core Principles of the UN Charter
- Art. 1: Purposes
- Maintenance of international peace and security
- Development of friendly relations among nations
- Promotion of equal rights and self-determination of peoples
- Achievement of international cooperation
- Art. 2: Principles
1. Sovereign equality of all members
2. Fulfillment of Charter obligations
3. Peaceful settlement of disputes
4. Prohibition of the use of force and nonintervention
- States must respect each other’s territorial integrity and political
independence.
5. Collective assistance
6. Non-interference in domestic affairs
7. Applies to members and non-members alike (193 UN member states out of
~195-208 total states in 2024).
UNGA Resolution 2625 (1970) - Declaration on Principles of International Law Concerning
Friendly Relations
- Authoritative interpretation of Art. 1 and 2 of the UN Charter
- Codifies fundamental principles of IL, including:
- Prohibition of the use of force
, - Self-determination of peoples
- Peaceful settlement of disputes
- Non-intervention
- Sovereign equality
- Emphasizes that states must refrain from assisting secessionist movements that
violate territorial integrity (unless self-determination is being denied)
- Often cited as customary international law and a soft law instrument with legal value
in interpreting state behavior
Areas of International Law (Non-Exhaustive)
- General IL is the main focus of this course.
Typical Legal Questions in IL:
- What legal rules exist and apply in a specific situation?
- Was the action lawful?
- Who has which rights and obligations?
- How should the facts be subsumed under the applicable law
- How should rules be interpreted?
Subjects of International Law
- Subject of IL: An entity that possesses rights and obligations under IL and has legal
personality.
- Sovereign States remain the main actors with full legal personality.
- Other Recognized Subjects (Non-State Actors, NSAs)
, - The legal personality for specific NSAs is still evolving and often depends on context
or state consent. Regional and domestic mechanisms exist to bring these subjects to
court; however, in IL, these mechanisms rest within the hands of the State.
- State as Full Subject of IL
- Full powers: Rights, duties, and legal obligations.
- Sovereignty: Internal and external.
- Jurisdiction & Autonomy.
- Right to self-defense, relations with others, treaty-making capacity.
- Can bring/receive claims under IL.
- Membership in international organizations.
- Immunities and privileges under IL.
International Legal Personality: Functional Capacities
- Capacity to:
- Exercise jurisdiction (exclusive)
- Participate in law-making (treaties, customs)
- Enter into international agreements
- Bring legal claims and enforce rights
- Enjoy rights and immunities
- Be held accountable under IL
- Only States have full enforcement power under IL. Other subjects have limited
capacities despite contributing to international lawmaking.
Definition of a State: Montevideo Convention on the Rights and Duties of States (1934)
- Art. 1: Criteria
1. Permanent Population: Stable, resident community.
2. Defined Territory: Must have land, sea, and airspace under effective control.
- It does not require fixed borders; disputes do not nullify statehood.
3. Effective Government: Must exercise authority and maintain centralized order.
(Effective Control).
4. Capacity to enter into relations with other States
- Illustrative Case: Greenland
- Is Greenland a sovereign state? → No.
- While it has a permanent population, a defined territory, and a degree of self-
government, the capacity to enter into international relations still lies with
Denmark.
- This means Greenland does not meet all four Montevideo criteria for
statehood, particularly the external sovereignty component.
- Recognition of Statehood
1. Subjects of International Law
States and Compliance
Hobbes’ "State of Nature": Without law, there is chaos, a "war of all against all" (anarchy).
However, IL does not exist solely to prevent anarchy. It exists because:
1. It creates a structured system of valid legal arguments, obligations, and rights.
- IL provides a common legal language and framework for how states interact,
make claims, and resolve disputes.
- Without this structure, arguments would be inconsistent, opportunistic, and
unpredictable.
- States know what to expect from others and how to justify their actions; this
promotes stability and credibility.
- Example: When Palestine brings a claim to the ICC, it must follow proper
legal procedure (e.g., Art. 12 Rome Statute) and argue within IL frameworks,
not just political narratives.
2. It enables third-party adjudication and accountability.
- IL allows disputes to be handled by neutral bodies (e.g., ICJ, ICC) instead of
devolving into retaliation or force.
- Third-party adjudicators help apply the law objectively, ensuring fairness even
when power is unequal.
- This reduces reliance on power politics and enables smaller or weaker states
to seek justice.
- Example: The ICC’s investigation into alleged war crimes in Palestine enables
a legal forum to assess the conduct of powerful actors like Israel, without
requiring Palestine to resort to political or military means.
3. Unlike international relations (IR), which is based on power politics, IL is grounded in
legal rules and principles.
- IR allows states to act based on interest, strategy, and influence, but IL
imposes normative constraints based on agreed-upon rules.
- Legal rules reduce arbitrariness and encourage consistency, especially in
sensitive matters like sovereignty, war, or recognition.
- This enables long-term cooperation, predictability, and norm development.
- Example: The Montevideo criteria provide a legal, not political, basis for
evaluating statehood, even if a state is not powerful or widely recognized.
International Society of States: A Classical Perspective
- Key Characteristics:
- Universal: Includes nearly all existing states.
- Heterogeneous: Diverse cultures, values, and systems.
- Decentralized: No central authority; law depends on state consent.
- Interdependent: States rely on each other for resources, security, and trade.
, - Example: Berlin Conference (1884-85), Colonial partitioning of Africa
showed how international society operated in practice.
- This concept remains relevant despite the evolution of IL because the core features
of the international society of states (sovereign equality, decentralization, and state
consent) still form the foundation of modern IL.
- Even with the rise of human rights, IOs, and NSAs, states remain the primary
legal subjects, and most legal obligations still depend on their consent (e.g.,
treaties, recognition).
- Thus, understanding IL through the lens of a state-based, decentralized
system is still essential for explaining how IL operates in practice.
International Community (Post-Cold War, European Perspective)
- More recent, post-decolonization development.
- Key Characteristics:
- Organized and rule-based.
- Decolonized: Right to self-determination emphasized.
- Humanization of IL:
- Emergence of Human Rights Law, International Criminal Law,
Environmental Law, Law of the Sea, Law of Common Heritage, rights
for future generations, etc.
- Shared values, solidarity, and cooperation among states while preserving
sovereignty.
- Emphasis on individuals and non-state actors (NSAs) as part of the IL system.
- European teaching of IL reflects these values more than in other regions.
Core Principles of the UN Charter
- Art. 1: Purposes
- Maintenance of international peace and security
- Development of friendly relations among nations
- Promotion of equal rights and self-determination of peoples
- Achievement of international cooperation
- Art. 2: Principles
1. Sovereign equality of all members
2. Fulfillment of Charter obligations
3. Peaceful settlement of disputes
4. Prohibition of the use of force and nonintervention
- States must respect each other’s territorial integrity and political
independence.
5. Collective assistance
6. Non-interference in domestic affairs
7. Applies to members and non-members alike (193 UN member states out of
~195-208 total states in 2024).
UNGA Resolution 2625 (1970) - Declaration on Principles of International Law Concerning
Friendly Relations
- Authoritative interpretation of Art. 1 and 2 of the UN Charter
- Codifies fundamental principles of IL, including:
- Prohibition of the use of force
, - Self-determination of peoples
- Peaceful settlement of disputes
- Non-intervention
- Sovereign equality
- Emphasizes that states must refrain from assisting secessionist movements that
violate territorial integrity (unless self-determination is being denied)
- Often cited as customary international law and a soft law instrument with legal value
in interpreting state behavior
Areas of International Law (Non-Exhaustive)
- General IL is the main focus of this course.
Typical Legal Questions in IL:
- What legal rules exist and apply in a specific situation?
- Was the action lawful?
- Who has which rights and obligations?
- How should the facts be subsumed under the applicable law
- How should rules be interpreted?
Subjects of International Law
- Subject of IL: An entity that possesses rights and obligations under IL and has legal
personality.
- Sovereign States remain the main actors with full legal personality.
- Other Recognized Subjects (Non-State Actors, NSAs)
, - The legal personality for specific NSAs is still evolving and often depends on context
or state consent. Regional and domestic mechanisms exist to bring these subjects to
court; however, in IL, these mechanisms rest within the hands of the State.
- State as Full Subject of IL
- Full powers: Rights, duties, and legal obligations.
- Sovereignty: Internal and external.
- Jurisdiction & Autonomy.
- Right to self-defense, relations with others, treaty-making capacity.
- Can bring/receive claims under IL.
- Membership in international organizations.
- Immunities and privileges under IL.
International Legal Personality: Functional Capacities
- Capacity to:
- Exercise jurisdiction (exclusive)
- Participate in law-making (treaties, customs)
- Enter into international agreements
- Bring legal claims and enforce rights
- Enjoy rights and immunities
- Be held accountable under IL
- Only States have full enforcement power under IL. Other subjects have limited
capacities despite contributing to international lawmaking.
Definition of a State: Montevideo Convention on the Rights and Duties of States (1934)
- Art. 1: Criteria
1. Permanent Population: Stable, resident community.
2. Defined Territory: Must have land, sea, and airspace under effective control.
- It does not require fixed borders; disputes do not nullify statehood.
3. Effective Government: Must exercise authority and maintain centralized order.
(Effective Control).
4. Capacity to enter into relations with other States
- Illustrative Case: Greenland
- Is Greenland a sovereign state? → No.
- While it has a permanent population, a defined territory, and a degree of self-
government, the capacity to enter into international relations still lies with
Denmark.
- This means Greenland does not meet all four Montevideo criteria for
statehood, particularly the external sovereignty component.
- Recognition of Statehood