Public International Law Unit 2 focuses on states as the primary subjects of international law, the legal criteria for statehood under the Montevideo Convention 1933, competing theories of state recognition, and the principles governing state territorial sovereignty. These foundational concepts define how sovereign political entities acquire international legal personality, exercise exclusive jurisdiction within territorial boundaries, and interact in the global legal order.
1. States as Primary Subjects of International Law
In international jurisprudence, a subject of international law is an entity possessing international legal personality, capable of enjoying international rights, bearing international legal duties, and bringing international claims before tribunals. While international organizations and individuals hold derivative or limited international personality, sovereign states remain the original and principal subjects of international law.
Statehood grants full legal capacity to conclude treaties, maintain diplomatic relations, exercise sovereign immunity, and participate in international customary law-making. Modern international legal development confirms that non-state actors possess capacity only to the extent conferred by sovereign states through bilateral or multilateral treaties.
2. Legal Criteria of Statehood: The Montevideo Convention 1933
Article 1 of the Montevideo Convention on the Rights and Duties of States 1933 sets forth the four classical qualifications for an entity to claim statehood under customary international law:
- Permanent Population: A stable human community inhabiting the territory on a permanent basis. International law does not mandate a minimum population threshold, meaning small population states enjoy equal legal capacity.
- Defined Territory: A distinct geographical portion of the earth's surface where the community resides. Border disputes or unsettled frontiers do not invalidate statehood, provided there is an identifiable territorial core under administrative control.
- Government: An organized political authority capable of exercising effective governance and maintaining public order over the population and territory without external administrative dependence.
- Capacity to Enter into Relations with Other States: The legal and practical competence to conduct foreign relations, enter into international agreements, and engage in diplomatic discourse independently without subordination to another sovereign.
3. Theories of State Recognition
Recognition is the formal unilateral act by which one or more existing states acknowledge that a political entity fulfills the conditions of statehood and express willingness to treat it as an international person. International jurists have developed two distinct theoretical frameworks to explain recognition:
A. Declarative (Evidentiary) Theory
The declarative theory holds that statehood is a matter of pure legal fact. Once an entity satisfies the objective criteria of the Montevideo Convention (population, territory, government, and capacity), it becomes a state automatically by operation of international law. Recognition by other states merely declares or acknowledges an existing legal reality. Article 3 of the Montevideo Convention adopts this view, declaring that the political existence of a state is independent of recognition by other states.
B. Constitutive Theory
The constitutive theory asserts that an entity becomes an international person solely through the act of recognition by other sovereign states. Under this view, prior to diplomatic recognition, an entity possesses no international legal rights or obligations. Modern international state practice predominantly favors the declarative theory, although recognition remains politically critical for establishing bilateral diplomatic and commercial ties.
C. Modes of Recognition: De Facto vs. De Jure
States extend recognition in two primary forms depending on factual stability:
- De Facto Recognition: A provisional or conditional recognition granted when an authority exercises effective control over territory, but doubts remain regarding its permanence, constitutional legitimacy, or complete stability.
- De Jure Recognition: A final, irrevocable, and complete recognition granted when a government is deemed fully established, legally legitimate, and capable of fulfilling long-term international obligations.
4. State Territorial Sovereignty and Jurisdiction
Territorial sovereignty signifies the exclusive right and competence of a state to exercise supreme political authority and jurisdiction over all persons, property, and events situated within its defined territorial borders to the exclusion of other states. The principle of sovereign equality enshrined in Article 2(1) of the United Nations Charter guarantees this territorial inviolability.
Students studying specialized legal studies and curriculum notes will recognize that territorial sovereignty includes the land domain, internal waters, territorial sea (ordinarily extending up to 12 nautical miles), and the superjacent airspace above the land and territorial waters. Within this sovereign territory, domestic municipal law operates supreme.
5. Modes of Acquiring and Losing Territorial Sovereignty
Traditional customary international law recognizes five primary modes of acquiring territory:
- Occupation: Establishing effective sovereign control over terra nullius (territory belonging to no existing sovereign state) through peaceful settlement and administrative display.
- Accretion: Geographical addition of land to existing state territory through natural physical processes, such as river alluvium, silt deposition, or volcanic activity.
- Cession: The voluntary transfer of territory from one sovereign state to another through a formal international treaty, sale, or exchange.
- Prescription: Acquiring territory through continuous, peaceful, and uninterrupted display of sovereign authority over an extended period with the acquiescence of the former sovereign.
- Conquest / Annexation: Historically recognized, but strictly prohibited in modern international law under Article 2(4) of the UN Charter, which forbids the threat or use of force against the territorial integrity of any state.
Understanding how states exercise constitutional sovereignty and sovereign institutional authority helps clarify the relationship between internal administrative governance and international legal personality.
6. Non-Intervention and State Responsibility
A corollary of territorial sovereignty is the customary principle of non-intervention in the domestic affairs of other states. Every sovereign state is duty-bound to refrain from subversive actions, armed incursions, or unauthorized extraterritorial enforcement within the boundaries of another nation. When a state breaches an international obligation, it incurs international state responsibility, giving rise to duties of cessation, restitution, and compensation under international law.
Summary of Core Examination Principles
When answering examination questions on Public International Law Unit 2, students should structure their responses around these core propositions:
- States possess original, plenary international legal personality under customary international law.
- The Montevideo criteria establish the four objective requirements for statehood: population, territory, effective government, and international capacity.
- The declarative theory reflects the prevailing modern standard, treating recognition as acknowledgment of existing statehood rather than a condition precedent.
- Territorial sovereignty grants exclusive domestic jurisdiction subject only to obligations established under international treaties and customary international law.
- Modern international law prohibits territorial acquisition through conquest or forceful annexation under the United Nations Charter.