Monist Theory

The relationship between international law and municipal law (also known as national or domestic law) is a fundamental question in international law. Two main theoretical approaches attempt to explain this relationship: Monism and Dualism.

International law and municipal law are part of a single legal order

The Monist theory posits that international law and municipal law are not distinct or separate legal systems, but rather form part of a single, unified legal order. In a monist system, international law is automatically incorporated into the domestic legal system and can be directly applied by national courts without the need for any specific legislative act to transform it into domestic law.

From a monist perspective, international law is considered superior to, or at least on the same level as, municipal law. If there is a conflict between a rule of international law and a rule of municipal law, the rule of international law prevails. This perspective views the individual as the ultimate subject of both international and domestic law, with international law potentially creating rights and obligations for individuals directly.

Different versions of monism exist. Some argue for the absolute supremacy of international law, while others suggest a hierarchy where international law is generally superior but specific constitutional provisions of the state might create complexities.

Proponents of monism often point to the practical application of international law in areas like human rights or international criminal law, where international norms are increasingly seen as directly applicable within states, even without explicit domestic legislation. However, even in states leaning towards monism, there are often practical requirements, such as publication, before an international norm is fully applicable domestically.

Dualist Theory

The Dualist theory presents a contrasting view to monism regarding the relationship between international and municipal law.

International law and municipal law are separate and distinct legal systems

According to the Dualist theory, international law and municipal law are entirely separate and distinct legal systems. They operate on different planes and regulate different subjects. International law governs the relations between states, while municipal law governs the relations between individuals within a state or between individuals and the state.

From this perspective, international law cannot, as such, be directly applied within the domestic legal system of a state. For a rule of international law to have effect in a state's domestic courts or legal system, it must be transformed or incorporated into municipal law through a specific legislative act. This usually takes the form of an Act of Parliament or a similar legislative measure that explicitly adopts the international rule and makes it part of domestic law.

In case of a conflict between international law and municipal law, a dualist system typically holds that domestic courts are bound to apply municipal law, even if it is contrary to the state's international obligations. The state might be held responsible at the international level for breaching its obligations, but the domestic court will apply the domestic rule.

Many states, including India, exhibit characteristics of both monist and dualist approaches, though generally leaning towards dualism, particularly regarding treaties. For treaties to become part of Indian domestic law and enforceable by Indian courts, they typically require enabling legislation by the Parliament. Customary international law, however, is sometimes seen as automatically incorporated unless it conflicts with existing statutory law.

The debate between monism and dualism is primarily theoretical, and in practice, most states adopt a mixed approach, often determined by their constitutional framework and specific legal traditions.

Incorporation Theory

The debate between Monism and Dualism gives rise to two practical approaches regarding how international law becomes applicable within a state's domestic legal system: the Theory of Incorporation and the Theory of Transformation.

International law automatically becomes part of municipal law

The Incorporation Theory (often associated with Monism) holds that rules of international law, particularly customary international law, are automatically considered part of the domestic law of a state without the need for specific legislative action. These rules are seen as being "incorporated" into the municipal legal system from the moment they become established rules of international law.

According to this theory, domestic courts can directly apply rules of international law, provided they are not in conflict with existing statutory law or constitutional provisions. The judiciary plays a key role in identifying and applying these international norms. This approach views international law as part of the 'law of the land'.

While more readily applied to customary international law, some versions of this theory also suggest that certain types of treaties, particularly those dealing with universally accepted norms or human rights, might be capable of direct application if they are 'self-executing' (meaning they are sufficiently clear and specific to be applied without further legislation).

States that lean towards the incorporation theory often have constitutional provisions or judicial traditions that recognise the direct applicability of international law, especially customary international law.

Transformation Theory

International law requires specific legislative action to become part of municipal law

The Transformation Theory (often associated with Dualism) asserts that international law does not automatically become part of a state's domestic law. For international law to have any effect within the municipal legal system, it must undergo a process of "transformation". This transformation is achieved through specific legislative action by the domestic legislature.

Under this theory, international treaties or rules of customary international law are considered external to the domestic legal system. They create obligations for the state at the international level, but they do not directly create rights or obligations for individuals within the state, nor can they be directly applied by domestic courts. The legislature must pass an Act of Parliament or similar law that specifically incorporates the international rule into domestic law, giving it the force of municipal law.

The legislative act essentially transforms the international obligation into a domestic legal rule. If the legislature fails to enact such a transforming law, the international rule remains binding on the state internationally but is not part of the domestic legal system and cannot be enforced by domestic courts.

This theory emphasises the sovereignty of the state and the supremacy of its domestic legislature in determining what constitutes domestic law. It provides clarity and ensures that domestic law is made through constitutional processes. However, it can potentially lead to situations where a state is in breach of its international obligations because its domestic law is inconsistent or because the necessary transforming legislation has not been enacted.

Indian Approach

Relying on the Constitution and judicial interpretation

India's approach to the relationship between international law and municipal law is a blend of both Transformation and Incorporation theories, though it significantly leans towards Transformation, particularly regarding treaties. The approach is primarily guided by the Indian Constitution and interpretations by the Indian Supreme Court and High Courts.

Constitutional Provisions:

Article 51 of the Indian Constitution, under the Directive Principles of State Policy, states that the State shall endeavour to:

1. Promote international peace and security.
2. Maintain just and honourable relations between nations.
3. Foster respect for international law and treaty obligations in the dealings of organised peoples with one another.
4. Encourage settlement of international disputes by arbitration.

While Article 51 signifies India's commitment to international law, it is a Directive Principle, not directly enforceable by courts. It serves as a guide for policy-making and interpretation.

Article 253 grants Parliament the power to make any law for the whole or any part of the territory of India for implementing any treaty, agreement, or convention with any other country or any decision made at any international conference, association, or other body. This article provides the constitutional basis for the Transformation Theory concerning treaties – Parliament can enact legislation to give effect to international agreements domestically.

Treaties: In India, treaties generally do not become part of domestic law automatically upon ratification. They require enabling legislation passed by Parliament under Article 253 to be enforceable by domestic courts and to create rights or obligations for individuals. Without such legislation, a treaty is binding on India at the international level but has no direct domestic legal effect. This aligns with the Transformation Theory.

Customary International Law: The position regarding customary international law is less clear-cut but tends towards a degree of incorporation, provided it is not inconsistent with existing statutes or the Constitution. Indian courts have, on occasion, referred to and applied rules of customary international law, especially in areas like human rights or humanitarian law, where there is a lack of specific domestic legislation. The principle here is often that customary international law is part of Indian law unless it is contrary to enacted legislation.

Judicial Interpretation: The Indian judiciary has played a crucial role in integrating international law norms into the domestic legal system, particularly in the field of human rights. The Supreme Court has sometimes read international human rights norms into fundamental rights guaranteed by the Constitution, especially when there is no conflicting domestic law. This approach reflects a practical move towards incorporating international standards through judicial interpretation, even without explicit transforming legislation in every instance.

In essence, India follows a mixed approach. Treaties primarily require legislative transformation. Customary international law may be considered incorporated unless contradicted by domestic law. Judicial interpretation acts as a bridge, particularly in constitutional matters, to align domestic law with international standards where possible.