International Law and Municipal Law

It follows that a rule of international law is part of national law without any act of transformation, that national courts should apply it, and that in case of conflict international law prevails, because on this view it is the higher of the two.

Its two versions

Kelsen's version is the strict one. Every norm derives its validity from a higher norm, and the chain ends in a Grundnorm. Kelsen located the basic norm in international law, so municipal legal orders derive their validity from it. That is the position described in [Theories of the Basis of International Law].

The natural-law version holds that both systems derive from the same higher law, so neither can contradict the other.

What is right about it

It reflects how the international plane actually works. Article 27 means that from the outside a State's internal law is simply a fact and never a justification.

It also reflects how many States actually behave with custom: a great many legal systems, including the English and the Indian, apply customary international law without any legislation, which is a monist practice whatever the theory says.

What is wrong with it

No State applies it fully. Every legal system reserves the power of its legislature to override, and a monism that lets an unincorporated treaty defeat a statute would put the treaty-making executive above the legislature. That is a constitutional objection, not a technical one.

The two systems have different subjects. International law binds States primarily; municipal law binds individuals. Treating them as one order requires the claim that international law ultimately regulates individuals too, which is arguable but not obvious.

It cannot explain the transformation practice. If international law were automatically part of national law, the elaborate machinery States maintain for incorporating treaties would be pointless.

Dualism

What it says

The two are separate legal systems, and the classic statement of the differences comes from Triepel and Anzilotti.

Different sources. International law comes from the common will of States; municipal law comes from the will of a single State.

Different subjects. International law regulates States; municipal law regulates individuals.

Different subject matter. International law governs relations between States; municipal law governs relations within a State.

It follows that a rule of international law can have no effect inside a State until that State makes it part of its own law, by legislation or otherwise. That process is transformation.

What is right about it

It matches most States' actual constitutional practice for treaties. In India, in the United Kingdom, in Canada, in Australia, a treaty concluded by the executive does not by itself change the law that courts apply.

It also protects the legislature. Since the treaty-making power is executive almost everywhere, unmediated monism would let the executive legislate by treaty.

What is wrong with it

It is too tidy about subjects. Individuals now have rights and duties directly under international law, as [Subjects of International Law] shows, so the clean division between systems by whom they bind is no longer accurate.

It does not describe how custom is treated. Most dualist States apply customary international law without transformation.

It can produce embarrassment. A State can be in clear breach on the international plane while its own courts are obliged to apply the statute that produced the breach.

The doctrines that do the work

The theories are labels; these three doctrines are what a court actually applies.

The doctrine of incorporation, sometimes called adoption. Rules of international law are part of the law of the land automatically, unless they conflict with an Act of Parliament or with settled judicial decision. This is the general position for custom in India and in England.

The doctrine of transformation. Rules of international law are not part of the law of the land unless they have been made so by legislation, judicial decision or long established usage. This is the general position for treaties in India and in England.

Consistent interpretation, sometimes called the presumption of conformity. Where a statute is capable of two readings, a court prefers the reading that conforms to the State's international obligations, because the legislature is presumed not to intend a breach. This is the most practically useful of the three, because it operates even where a treaty has not been incorporated, and its Indian statement is in [International Law in Indian Courts].

Comparative practice, briefly

The United Kingdom. Custom is incorporated; treaties require legislation; a statute prevails over both.

The United States. Article VI of the Constitution makes treaties made under the authority of the United States part of the supreme law of the land, which looks strongly monist. The effect is cut down by the distinction between self-executing and non-self-executing treaties, the latter needing implementing legislation, and by the rule that a later statute prevails over an earlier treaty as a matter of domestic law.

The Netherlands and several civil-law States. Constitutions provide expressly that treaties, once published, have effect and may prevail even over the constitution in defined cases. This is the closest practice comes to genuine monism.

India is dealt with in the next chapter.

A worked example

State D, a dualist State, ratifies a convention requiring it to make torture a criminal offence. Parliament passes no legislation. Two years later an official of State D tortures a detainee. The detainee sues in State D's courts, relying on the convention.

On the international plane. State D is in breach. Article 26 requires performance in good faith and article 27 prevents it pleading the absence of legislation as an excuse. Another State party may invoke its responsibility.

In State D's courts. The convention is not part of the law of the land, so the court cannot convict on it or award damages under it. That is dualism doing what it does.

Is that the end? No, and this is where a good answer separates itself. If any existing statute or constitutional guarantee is capable of a reading that conforms to the convention, the court should prefer that reading. If State D's constitution guarantees life and personal liberty, the convention can inform its content without being incorporated. And if the prohibition of torture is a rule of customary international law, then in a State that incorporates custom the court may apply it directly, since the barrier is to unincorporated treaties and not to custom.

Change the facts: State D's own statute expressly authorises the conduct. Now consistent interpretation is unavailable, because the statute is not capable of two readings. The court must apply the statute, and State D remains in breach internationally. That is the embarrassment dualism produces, and the remedy is political rather than judicial.

Distinctions table

What it does NOT mean

No State is purely monist or purely dualist. Almost every system incorporates custom and transforms treaties, which is a mixture. Describing India or England as "dualist" without that qualification is a half-truth.

Dualism does not mean international law is ignored. It means it operates on a different plane, and it reaches national law through incorporation, through legislation, and above all through consistent interpretation.

A treaty that has not been incorporated is not useless in a national court. It can be used to construe a statute, to inform a constitutional guarantee, and to resolve ambiguity.

Monism does not mean a treaty always beats a statute. Even in strongly monist systems the effect depends on constitutional provisions about self-executing treaties and about which prevails on conflict.

Limits and criticism

The debate is largely about description, not decision. Courts do not decide cases by choosing a theory; they apply their own constitution's rules about treaties and custom, and the theories are labels attached afterwards.

The labels obscure the interesting question. What matters is not whether a system is monist but which rules of international law are directly applicable, at whose instance, and with what rank. Those questions have different answers for custom, for treaties, for peremptory norms and for decisions of international organisations, and no single label captures the pattern.

The gap the debate leaves is real. In dualist practice a State can be in breach internationally while its courts are compelled to apply the offending statute, and neither theory solves that; only legislation does.

Quick revision

Monism: one legal order; international law is automatically part of national law and prevails on conflict. Kelsen, with the Grundnorm in international law.

Dualism: two systems, differing in sources, subjects and subject matter; international law applies internally only after transformation. Triepel and Anzilotti.

Article 27 VCLT: a party may not invoke its internal law as justification for failure to perform a treaty. Article 46: consent given in violation of internal law on competence may be invoked only if the violation was manifest and concerned a rule of fundamental importance.

Three working doctrines: incorporation (custom, automatically), transformation (treaties, by legislation), and consistent interpretation, which operates even on an unincorporated treaty.

Practice: the United Kingdom incorporates custom and transforms treaties; the United States makes treaties supreme law but distinguishes self-executing from non-self-executing; several civil-law constitutions give treaties direct effect.

No State is purely one or the other.

Test yourself

1. State the monist and dualist positions and name their chief exponents.

Monism holds that international law and municipal law form a single legal order, so that a rule of international law is part of national law without transformation and prevails in case of conflict; Kelsen is its chief exponent, locating the Grundnorm of the whole legal order in international law. Dualism holds that they are separate systems differing in their sources, their subjects and their subject matter, so that international law operates within a State only when transformed into national law; Triepel and Anzilotti are its chief exponents.

2. Can a State plead its own constitution as a defence to a breach of treaty?

No. Article 27 of the Vienna Convention provides that a party may not invoke the provisions of its internal law as justification for its failure to perform a treaty. The only qualification is article 46, which looks the other way: a State may not invoke a violation of its internal law on competence to conclude treaties as invalidating its consent unless the violation was manifest and concerned a rule of internal law of fundamental importance, a violation being manifest if it would be objectively evident to any State conducting itself in accordance with normal practice and in good faith.

3. Distinguish incorporation from transformation.

Under incorporation, rules of international law become part of the law of the land automatically and are applied by national courts unless they conflict with a statute or settled judicial decision. Under transformation, they are not part of the law of the land unless made so by legislation, judicial decision or long established usage. Most systems, including the Indian and the English, incorporate custom and transform treaties, so the two doctrines operate side by side within one legal system on different classes of rule.

4. A treaty has been ratified but not implemented by legislation. What use is it in a national court of a dualist State?

It cannot be the direct source of a right or an offence, because it is not part of the law of the land. It remains useful in three ways. It can be used to construe an ambiguous statute, on the presumption that the legislature does not intend to legislate contrary to the State's international obligations. It can inform the content of a constitutional guarantee expressed in general terms. And where its content is also a rule of customary international law, the court may apply that rule directly if the system incorporates custom, because the barrier is to unincorporated treaties and not to custom.

5. "Neither monism nor dualism describes any real legal system." Discuss.

The statement is close to true. Almost every system applies customary international law without legislation, which is monist, and requires legislation before a treaty changes the law courts apply, which is dualist. The United States is often called monist because article VI makes treaties the supreme law of the land, yet it distinguishes self-executing from non-self-executing treaties and lets a later statute prevail domestically over an earlier treaty. The theories are best treated as descriptions of two tendencies, and the useful questions are which rules are directly applicable, at whose instance, and with what rank, which have different answers for custom, treaties and peremptory norms.

6. What is the presumption of conformity, and why is it the most useful of the three doctrines?

It is the rule of construction that where a statute is capable of more than one meaning, a court prefers the meaning that conforms to the State's international obligations, because the legislature is presumed not to intend a breach. It is the most useful because it operates without incorporation and without legislation, so it reaches unincorporated treaties, and because it applies in the great majority of cases, where the question is what a statute means rather than whether it is valid. Its limit is that it cannot be used where the statute admits of only one reading, and in that case the court must apply the statute and the State remains in breach.