History of International Law

Decentralized System and Sovereignty

• Decentralized system implies no single leader or legislature, and every state is responsible for its own actions.
• States with parliament and judges coexist, and sovereignty is a key concept.

Peace of Westphalia (1648)

• Established the framework for international law, with every state equal regardless of size.
• Introduced the principle of sovereignty, where states have full power within their territory.
• Key principles include:
  • Territorial sovereignty: non-interference by other states, with exceptions.
  • Legal equality of states: one state, one vote, regardless of size or economic power.
  • State consent as the basis of international obligations.
  • Minimal rules of coexistence.
  • Principle of non-intervention in internal matters of third states.

Structural Differences between National Law and Classical International Law

• Horizontal vs. vertical structure: national law has a central government, while international law lacks one.
• State is the only legal subject, with no national organizations or companies as actors.
• No parliament, informal law-making process, scarce legal rules, and no hierarchy of norms.
• No judiciary, with self-help often through military means.

Evolution of International Law

• From natural law to positive law, with a focus on state consent.
• Modern international law system:
  • More actors, including states, transnational cooperations, NGOs, and individuals.
  • Expansion of areas of regulation.
  • Creation of institutional methods of enforcement.

Sources of International Law

• Article 38 of the ICJ Statute:
  • Primary sources: international conventions, international custom, and general principles of law.
  • Secondary sources: judicial decisions and teachings of highly qualified publicists.
• No hierarchy of sources, with all sources having equal standing.

Hierarchy of Rules

• Fundamentals that keep the international community together.
• Jus cogens norms: peremptory norms that apply even without state consent.
• Examples of jus cogens norms: prohibitions of aggression, crime against humanity, torture, slavery, and genocide.

United Nations and International Law

• Established on solid Westphalian principles, with respect for equal rights and self-determination.
• UN Charter:
  • Introduced a ban on the use of force.
  • Established the Security Council to maintain international peace and security.
• General Assembly: consultative role, with all member states represented.
• International Law Commission: promoting the progressive development of international law and its codification.

Jus Cogens and Obligations Erga Omnes

• Jus cogens norms are fundamental and non-derogable.
• Obligations erga omnes: everyone has standing, and states can bring others to court for infringement of these norms.
• Distinction between erga omnes and jus cogens: not all erga omnes obligations are jus cogens.
• Human rights and jus cogens: while human rights are fundamental, not all human rights norms are considered jus cogens.

Structural Differences between National Law and Classical International Law

• In a modern democratic state, there is a central government with a division of power, whereas classical international law reflected a horizontal structure with no central government.
• In classical international law, the state was the only legal subject, with no national organizations, parliament, or judiciary.

Key Features of Classical International Law

• No central government, parliament, or judiciary
• Informal law-making process with scarce legal rules and no hierarchy of norms
• Regulations of the assembly were just recommendations
• No judiciary; self-help, often by military means

Evolution of International Law

• Moved from natural law to positive law, which does not envisage a universal legal system, but rather one that is fragmented and in which states are bound by different legal obligations

Modern International Law System

• More actors have entered the system, including states, transnational corporations, NGOs, and individuals
• The state remains the central actor, but new actors have emerged and revolve around it
• Expansion of areas of regulation and creation of institutional methods of enforcement

Sources of International Law (Article 38 ICJ Statute)

• Primary sources:
  • International conventions, whether general or particular, establishing rules expressly recognized by the contesting states
  • International custom, as evidence of a general practice accepted as law
  • General principles of law recognized by civilized nations
• Secondary sources:
  • 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

Hierarchy of Rules

• Treaties have the same rank as general principles, with no hierarchy of sources
• Two legal principles for settling conflicts of laws:
  • Lex posterior derogat priori (new law derogates from old law)
  • Lex specialis derogat legi generali (specific law derogates from general law)

Jus Cogens Norms

• Refers to generally applicable international legal norms that are mandatory and non-derogable
• Examples include prohibitions of aggression, crimes against humanity, torture, slavery, and genocide
• Art 53 of the Vienna Convention defines jus cogens norms as those accepted and recognized by the international community of states as a norm from which no derogation is permitted

Primary Sources of International Law

• International conventions establishing rules recognized by contesting states, e.g., treaties
  • State consent is essential, and they are bound by the treaty by consent
• International custom, evidenced by general practice accepted as law
• General principles of law recognized by civilized nations, e.g., good faith, fair trial, equality

Secondary Sources of International Law

• Judicial decisions and teachings of highly qualified publicists of various nations, as subsidiary means for determining rules of law
  • Judicial decisions and teachings about the rule of law

Hierarchy of Sources

• No hierarchy of sources; sources are autonomous
• Treaties have the same rank as general principles
• Conflicts of laws are settled according to two legal principles:
  1. Lex posterior derogat priori (new law derogates from old law)
  2. Lex specialis derogat legi generali (specific law prevails over general law)

Fundamentals of International Law

• Jus cogens norms (peremptory norms) are fundamental international legal norms
  • Apply even if states do not expressly endorse them
  • Mandatory international law, e.g., prohibitions of aggression, crime against humanity, torture, slavery, genocide
• Obligations erga omnes: everyone has standing, e.g., human rights
  • Distinction between erga omnes and jus cogens: not all erga omnes obligations are jus cogens
  • Human rights and jus cogens: not all human rights norms are considered jus cogens

Development of International Law

• League of Nations (1919) and Permanent Court of International Justice (PCIJ)
• United Nations (UN) Charter: founding treaty of the UN
  • Introduced a ban on the use of force and gave collective competence to the Security Council
  • General Assembly: consultative role, organizational structure for all states
  • International Law Commission (ILC): promotes progressive development and codification of international law

Article 103 of the UN Charter

• Obligations under the UN Charter prevail over other international obligations