Public International Law Overview

• Public international law is the set of laws governing relations among states, international organizations, and individuals relevant to the international community.
• Key features of international law include sovereign equality, meaning all states have the same legal status and rights.
• The concept of sovereign equality was established in the Treaty of Westphalia and is in Article 2(1) of the UN Charter.
• Unlike national legal systems, international law lacks a global government, universal police force, and a single court.
• Countries follow international law by consent, and legal rules depend on what states agree to.
• A challenge in international law is its universal character conflicting with different legal traditions and cultures.
• International law promotes cooperation in trade, human rights, and climate change.
• International law remains a decentralized system where legal subjects create, interpret, and enforce the law.
• Modern international law is rooted in Europe during the Middle Ages, with the Pope and Catholic Church shaping rules for rulers and territories.
• An example of international law is the Geneva Conventions, setting rules for treating prisoners of war, wounded soldiers, and civilians.
• Reciprocity and the compliance pull are reasons why countries respect international law, even without a global police force.
• Countries risk losing diplomatic support, trade deals, or military alliances if they break international agreements.
• Public international law regulates the interrelationship of sovereign states while private international law handles cases with a foreign connection.
• Early legal principles influencing international law include treaties on trade, war, and diplomacy.
• During the Age of Exploration, legal scholars debated the rights of indigenous people and justifications for European conquests.
• Hugo Grotius emphasized the importance of rules for war and diplomacy.
• The Peace of Westphalia in 1648 established the idea of sovereign states, reducing the power of religious and imperial authorities.
• In the 19th century, international law became more structured with treaties and the rise of positivism.
• International organizations like the International Telegraph Union and the Universal Postal Union were established.
• Treaties were created to regulate war, such as the Hague Conventions.
• The League of Nations was formed after World War I but failed to prevent World War II.
• The UN replaced the League after World War II, creating a stronger framework for maintaining global peace.
• The UN is based on equal rights, self-determination, and sovereign equality.
• The UN Charter introduced rules against war, and the Security Council was authorized to enforce them.
• The Nuremberg Trials set a precedent for international criminal law.
• Post-war period saw the rise of the IMF and the World Bank.
• Organizations like NATO and the EU promoting economic and political cooperation.

Sources of International Law

• International law governs relationships between states and the ICJ defines it's sources.
• Article 38 of the ICJ Statute notes main sources: treaties, customary international law, general principles of law, judicial decisions, and scholarly writings.
• Treaties are formal agreements creating binding obligations between states.
• Customary international law consists of state practices becoming legally binding over time
• General principles of law are fundamental legal concepts recognized by many nations.
• Judicial decisions and scholarly writings support interpreting and applying legal rules.
• States act as both the legislative and executive branches, and international courts/tribunals form the judiciary.
• Treaties or conventions are a direct way for states to establish legal rights and obligations which require state consent and are binding only on consenting parties.
• Some treaties create international organizations, such as the UN and the EU, with the power to adopt legally binding rules.
• The Vienna Convention on the Law of Treaties is an authoritative set of rules regarding treaties with practically the entire treaty accepted as customary international law by the ICJ.
• According to Article 2(1)(a) of the Vienna Convention, a treaty is an international agreement between States in written form and governed by international law, whatever its designation.
• The principle of pacta sunt servanda means states bound to honor their treaty-based obligations.
• Treaties are a primary source of international law and their title does not determine their legal effect however intention matters.
• A bilateral treaty is between two states, concerning a specific issue of mutual interest.
• Multilateral treaties involve multiple states and establish general rules for all signatories including when a treaty creates an international organization, known as a constituent treaty organization has the authority to adopt legally binding rules states agree to be bound by any future legal instruments adopted under that treaty
• Law-making treaties establish general rules and obligations while Treaty-contracts are agreements between two or more states that regulate specific matters
• Conflicts between legal norms in international law are resolved using principles like lex specialis, lex posterior, and lex superior.
• Lex specialis law that specifically addresses a subject takes precedence over a more general law.
• Lex posterior law overrides an older law when both govern the same subject.
• Lex superior ranking law takes precedence over a lower-ranking law example: UN Security Council.

Consent, Jus Cogens & Customary Law

• A state is not bound by a treaty unless it has given its explicit consent.
• States are always bound by jus cogens meaning fundamental principles of international law that cannot be overridden.
• Customary international law is created when countries behave in a certain way and believe that this behavior is legally required.
• State practice means that countries must follow a specific behavior in a consistent and widespread manner.
• Opinio juris refers to the belief that an international legal right or obligation exists.
• Once a rule becomes customary law, it is binding on all states, including those that didn't help create it with the persistent objector rule a key exception.
• Jus cogens norms are fundamental rules that no state can reject, ex/ prohibitions on slavery, genocide and torture.
• When a treaty includes rules that are already part of customary international law, the states that sign the treaty are bound by both.
• The ICJ confirmed that the use of force between states is controlled by both the UN Charter and customary international law in the Nicaragua case.
• A treaty can help develop new customary law with treaties usually taking priority over customary law between signing states.

General Principles, Judicial Decisions & Soft Law

• General principles of law exist in national legal systems and are widely accepted as part of international law.
• Examples of general principles include pacta sunt servanda, good faith, estoppel, and liability for damages.
• The main purpose of general principles is to provide legal solutions when treaties and customary law don't offer clear answers.
• Judicial decisions are a secondary source of international law with the ICJ rulings binding on the parties involved.
• Rulings play an important role in interpreting international law and influencing future cases.
• The ICJ has contributed significantly to international legal principles but is not obligated to follow its previous rulings.
• Writings of legal scholars are the least authoritative source under Article 38(1).
• International Committee of the Red Cross (ICRC) published influential commentaries on the 1949 Geneva Conventions.
• Soft law instruments are agreements that are not legally binding but can still carry significant political costs although soft law does not create legal obligations.

Subjects of International Law

• Subjects of international law are actors with international rights and obligations.
• The primary subjects of international law are sovereign states, as they have the highest level of legal authority.
• Since 1945, non-state entities have gained increasing legal recognition.
• Legal personality in international law refers to the recognition of an entity as having rights and duties.
• The Montevideo Convention sets out key criteria that an entity must meet to be recognized as a state.
• Key criteria permanent population, defined territory, a government, and capacity to enter into relations with other states.
• There are two main theories about how a state is recognized in international law which include the declaratory theory and the constitutive theory.
• The right to self-determination is a rule of customary law, jus cogens, and erga omnes.
• Article 1 of the two International Covenants on Human Rights states all peoples have the right to freely determine their political status and shape their economic, social, and cultural development.
• Acquisition of new territory which consists of cession, accretion, occupation, and prescription.
• State succession happens when one state replaces another in controlling a territory's international relations with international law follows a clean slate approach.
• State extinction occurs when a country no longer meets the four criteria of statehood.
• Under international law, an international organization is an entity made up mostly of states and created by a treaty.
• In the Reparation for Injuries case, the ICJ ruled that being an international organization gives legal personality.
• The will theory, objective theory, and the presumptive personality theory, key theories for interpreting international organizations.
• In 2008, Kosovo's government declared independence from Serbia, raising the question of whether a unilateral declaration of independence was legal under international law.

Dapo Akande & the ICJ

• In November 2012, the UN General Assembly voted to grant Palestine the status of a non-member observer state.
• Palestine was eligible to ratify international treaties because it had been accepted as a member of UNESCO, a UN agency.
• With the new observer state status granted by the General Assembly, Palestine's position became even stronger which was one of the main reasons why Israel opposed the UN vote.
• There are two main theories about how a place becomes a state which includes the declaratory theory, and the constitutive theory.
• In Reparation for Injuries suffered, The ICJ ruled that the UN had the right to demand compensation when its workers were harmed in the line of duty.
• The ICJ ruled that the UN could seek two types of compensation, 1st reparation damage to the UN itself, and 2nd compensation for the victim or their family,
• The Montevideo Convention explains the basic requirements for a place to be considered a state giving a clear definition of what a state is and protecting new states from powerful countries.
• It establishes where international law comes from and how the court should apply giving treaties and international customs if none, it turns to international customs which consists of what countries have followed over time that is legally required.
• The ICJ applies general legal principles that are recognized by most states, and as a final the court can look to previous judicial decisions and the writings of legal scholars to clarify questions.
• The ICJ article 38 1 The Court, whose function is to decide in accordance with international law.