This document discusses the relationship between international law and municipal (domestic) law. There are two main theories - monism sees them as part of one legal system, dualism sees them as separate. Generally international law prevails in international forums. Treaties are binding even if domestic laws conflict. Domestically, conflicts can be reviewed by courts. The Philippines constitution incorporates international law, but restrictively to generally accepted principles. Jus cogens norms like prohibitions on aggression always prevail over domestic law, while other international laws can be opted out of.

1. International Law
28 August 2020
Atty. Ahmad Rais T. Undug

2. THE RELATIONSHIP BETWEEN
INTERNATIONAL LAW AND MUNICIPAL
LAW

3. Theories governing relationship
• 1. Monist Theory (Monism) – international law
and municipal law are part of one and the
same legal system; no conflict between the
two when they interact
• 2. Dualist Theory (Dualism) – international law
is an entirely separate and distinct legal
system from municipal law; there is always the
possibility of conflict between the two

4. Does a conflict really exist?
• From the point of view of an international
forum or tribunal:
– Naturally, international law shall prevail
– Municipal law can never prevail over international
law
– Possibility of a conflict between international law
and municipal law is remote
– As a rule, international law always prevails in the
international forum, not because it is superior, but
because it is the only law that applies

5. Does a conflict really exist?
• What happens when a country enters into a
treaty with another country and the
Constitution of the former runs afoul of the
terms of the treaty?
– Generally, a country cannot use its local law to
excuse itself from being bound by the terms of the
treaty

6. Does a conflict really exist?
• Under the 1987 Philippine Constitution:
– Article VIII Sec 5:
• Section 5. The Supreme Court shall have the following
powers:
– (2) Review, revise, reverse, modify, or affirm on appeal
or certiorari, as the law or the Rules of Court may provide,
final judgments and orders of lower courts in:
» (a) All cases in which the constitutionality or validity of
any treaty, international or executive agreement, law,
presidential decree, proclamation, order, instruction,
ordinance, or regulation is in question.

7. Does a conflict really exist?
• Therefore, under Philippine law, the Philippine
Supreme Court may declare a treaty or
international agreement unconstitutional
• However, this only has a domestic effect
• Philippine courts only have jurisdiction over
Philippine territory, and may or may not be
recognized by other states

8. Does a conflict really exist?
• If the issue is brought before an international
forum or tribunal, they do not have to take
cognizance of the decision of the Philippine
Supreme Court
• We are bound by the concept of pacta sunt
servanda (Latin: “Pacts must be respected”)
– “Every treaty in force is binding upon the parties
to it and must be performed in good faith.”
• Art. 26, Vienna Convention on the Law
of Treaties

9. Is such a conflict possible before a
domestic court?
• Can a conflict between international law and
municipal law be brought before a domestic
court?
• In the Philippine setting, YES
• Article II Sec 2, 1987 Philippine Constitution:
– The Philippines renounces war as an instrument of
national policy, adopts the generally accepted
principles of international law as part of the law of
the land and adheres to the policy of peace, equality,
justice, freedom, cooperation, and amity with all
nations. (a.k.a. The Incorporation Clause)

10. The Incorporation Clause in the PH
• Automatic – international law is automatically
incorporated as part of the law of the land
• Restrictive – limited only to principles of
international law that are considered to be
generally-accepted principles of international
law; jus cogens or customary norms of public
international law

11. The Incorporation Clause in the PH
• Principle of Transformation – incorporation
through legislative act
– Hard Transformation – Transformation of principles of
international law through statutes
• Example: The Convention on the Elimination of All Forms of
Discrimination Against Women (CEDAW) was codified into
municipal law through the passage of Republic Act No. 9262
or the Anti-Violence Against Women and Children Act
(VAWC)
– Soft Transformation – Through judicial decisions
• Principles of international law invoked by the Supreme Court
in its decisions form part of our legal system through
jurisprudential law

12. International law vs municipal law
• Which shall prevail in a domestic court?
– General rule: Lex Fori – The law of the forum or
court; that is, the law of the state or jurisdiction
where the action is brought.
– Relate to power of Supreme Court to decide on
constitutionality of treaties
– However, a distinction must be made between
principles of international law of a jus cogens
character and those of a jus dispositivum
character

13. Jus cogens vs jus dispositivum
• Jus cogens: norms of international law from
which no derogation is permitted
– Examples: principles of international law
outlawing aggression, genocide, crimes against
humanity, war crimes, piracy, slavery, torture, etc.
• In the case of jus cogens, it is international law
that shall prevail

14. Jus cogens vs jus dispositivum
• Jus dispositivum: Law adopted by consent.
The body of permissive general international
law, outside of jus cogens, which
accommodates opting-out, adjustment or
derogation, within private agreements,
domestic statutes or bilateral treaties.

15. How the US does it
• The Charming Betsy Canon:
– national statutes should be interpreted in such a
way that the interpretation does not conflict with
international laws
– an act of Congress ought never to be construed to
violate the law of nations if any other possible
construction remains