PUBLIC INTERNATIONAL LAW
Public International Law governs the relationship between sovereign states and international entities.
In the Philippines, international law is recognized as part of the law of the land, as affirmed by Article II, Section 2 of the 1987 Philippine Constitution, which provides that the Philippines adopts the generally accepted principles of international law as part of its legal system.
Below are the major subtopics of Public International Law in the Philippines, with relevant case laws.
Sources of International Law
The sources of international law, as recognized in Article 38 of the Statute of the International Court of Justice (ICJ), include treaties, customary international law, general principles of law recognized by civilized nations, judicial decisions, and teachings of the most qualified publicists.
These sources play a crucial role in shaping both global and domestic legal systems. The Constitution and Supreme Court decisions have reinforced the significance of these international law sources, integrating them into the national legal framework.
Treaties
Treaties are formal, legally binding agreements between States or international organizations.
In the Philippines, a treaty becomes domestically effective only after Senate concurrence, pursuant to Article VII, Section 21 of the 1987 Constitution.
The constitutional design creates a two-step process: (1) the President negotiates and signs;
(2) the Senate concurs by a two-thirds vote.
Without Senate concurrence, a treaty—no matter how important internationally—has no binding force in Philippine law.
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High-yield in Public International Law and Political Law. Frequently tested through treaty vs. executive agreement distinctions, Senate concurrence requirements, and traps assuming presidential signature alone is enough.
Pimentel v. Office of the Executive Secretary, G.R. No. 158088, July 6, 2005 (Supreme Court; Lawphil).
Senator Pimentel questioned the constitutionality of the Japan-Philippines Economic Partnership Agreement (JPEPA), arguing that it could not bind the Philippines without Senate concurrence. The Supreme Court agreed, holding that treaties require Senate concurrence to become valid and enforceable domestically. Until the Senate acts, a signed treaty remains ineffective in Philippine law.
🥜 A treaty binds the Philippines domestically only after Senate concurrence—presidential signature alone is insufficient.
Bayan Muna v. Romulo, G.R. No. 159618, February 1, 2011 (Supreme Court; Lawphil).
The case challenged the Mutual Logistics Support Agreement (MLSA) with the United States, claiming it required Senate concurrence. The Supreme Court ruled that the MLSA is an executive agreement, not a treaty, because it merely implements existing agreements, particularly the Visiting Forces Agreement (VFA), which had already received Senate concurrence. As such, no additional Senate approval was required.
🥜 Executive agreements that implement existing treaties or laws do not require Senate concurrence—only treaties creating new obligations do.
Customary
International Law
Customary international law consists of unwritten rules that develop from consistent State practice carried out with a sense of legal obligation (opinio juris).
These norms bind States even without a treaty and often protect basic human rights and liberty, especially where written law is silent. In Philippine law, customary international law may be applied directly by courts when consistent with the Constitution and fundamental rights.
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High-yield in Public International Law and Political Law. Frequently tested in problems involving aliens, deportation, detention, human rights, and limits on executive power.
A common trap is assuming aliens have no constitutional or human-rights protection—they do.
Mejoff v. Director of Prisons, G.R. No. L-4254, September 26, 1951 (Supreme Court; Lawphil).
Mejoff, a stateless alien ordered deported, remained detained for years because no country would accept him.
The Supreme Court granted habeas corpus and ordered his release, ruling that while the State may detain an alien pending deportation, detention cannot be indefinite when deportation is no longer reasonably possible. Prolonged detention without a realistic prospect of removal violates individual liberty and fundamental principles recognized under international law.
🥜 The State cannot detain an alien indefinitely for deportation—once removal is no longer feasible, continued detention is illegal.
General Principles of Law Recognized by Civilized Nations
General principles of law are core legal ideas shared across major legal systems—like due process, equity, good faith, and fairness.
They function as gap-fillers in international law when treaties and customary rules are silent or unclear. Courts rely on them to reach outcomes that are legally sound and system-consistent, especially in cross-border disputes involving liberty, procedure, or cooperation between states.
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Medium–High yield in Public International Law and Political Law. Often tested under sources of international law (Art. 38, ICJ Statute) and in extradition problems, where courts balance individual rights against international cooperation.
A common trap is assuming domestic constitutional rights apply wholesale to extradition.
Government of the United States of America v. Purganan, G.R. No. 148571, September 24, 2002 (Supreme Court; Lawphil).
The U.S. sought the extradition of Mark Jimenez under the RP–US Extradition Treaty. Jimenez applied for bail during the pendency of extradition proceedings, arguing entitlement to provisional liberty.
The Supreme Court reversed the grant of bail, holding that extradition proceedings are not criminal in nature, so the constitutional right to bail does not automatically apply.
Bail may be allowed only in exceptional circumstances, such as when detention would be clearly oppressive and supported by special humanitarian considerations—none of which were shown.
🥜 Bail is generally unavailable in extradition cases; it may be granted only in exceptional, humanitarian circumstances because extradition is not a criminal prosecution.
Judicial Decisions
Judicial decisions—whether from international tribunals (e.g., ICJ) or domestic courts—are not formal sources of international law, but they are important persuasive authorities.
They help interpret, apply, and develop international law, especially where treaty text is vague or customary rules are evolving. In Philippine practice, the Supreme Court often draws from international rulings and comparative jurisprudence when resolving cases involving treaties, extradition, human rights, and state obligations.
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Medium–High yield in Public International Law and Political Law, commonly tested under sources of international law (Art. 38, ICJ Statute) and in problems where courts reconcile international obligations with constitutional rights. A common trap is treating judicial decisions as binding sources rather than interpretative guides.
Secretary of Justice v. Lantion, G.R. No. 139465, January 18, 2000 (Supreme Court; Lawphil).
The U.S. requested the extradition of Mark Jimenez under the RP–US Extradition Treaty. During the DOJ’s evaluation, the Secretary of Justice withheld the request and documents from Jimenez, claiming confidentiality.
The Supreme Court held that due process applies even at the evaluation stage of extradition because the process affects liberty. A prospective extraditee has the right to be informed and to access relevant documents to prepare a defense; withholding them violates due process.
🥜 Due process applies at all stages of extradition—liberty interests require notice and access to documents even during preliminary evaluation.
Teachings of the Most Qualified Publicists
The teachings of qualified publicists—recognized scholars and experts in international law—are treated as subsidiary means for determining rules of international law.
They are not binding sources, but they help clarify, explain, and systematize treaties, customary international law, and general principles, especially when the law is uncertain, developing, or unsettled.
In the Philippine setting, the Supreme Court rarely cites publicists explicitly, but international law scholarship still shapes judicial reasoning, particularly in complex or novel cases. These writings function as persuasive authority, guiding courts when there is no controlling treaty, clear custom, or direct precedent.
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Medium yield in Public International Law. Often tested in questions on sources of international law (Article 38 of the ICJ Statute), with the trap being to overstate their authority—publicists inform the law; they do not create it.
Doctrines of International Law
International law is founded on several essential doctrines that shape how states interact with one another and how international actors conduct themselves on the global stage. These doctrines function as fundamental principles designed to uphold global order, safeguard human rights, and promote peaceful cooperation among nations.
By applying these doctrines in international courts and tribunals, the international community ensures that states are held accountable for their conduct, and that their legal obligations under international law are enforced. This system of accountability strengthens the rule of law across borders and helps to prevent conflict and injustice.
The Philippines, as an active member of the global community, recognizes and adheres to these key doctrines, both within its domestic legal framework and in fulfilling its commitments to international agreements.
The country’s participation in various international treaties and conventions is a testament to its ongoing role in upholding the principles of international law, ensuring that global standards are integrated into its national policies and practices.
These doctrines serve as foundational principles for resolving disputes, fostering cooperation, and maintaining global order. Below are some of the major doctrines in international law:
Doctrine of State Sovereignty
The Doctrine of State Sovereignty holds that every State has supreme authority within its own territory and is legally equal to all other States.
This means freedom from external coercion or interference in internal affairs—so long as the State respects the sovereignty of others and complies with international obligations. Sovereignty is foundational, but it is not absolute: it is bounded by rules on non-intervention, non-use of force, and treaty commitments.
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High-yield in Public International Law. Commonly tested with non-intervention, use of force, proxy warfare, and treaty breach issues.
A frequent trap is treating sovereignty as a license for intervention or ignoring limits imposed by customary law and treaties.
Military and Paramilitary Activities in and against Nicaragua
(Nicaragua v. United States), ICJ Reports 1986.
Nicaragua alleged that the U.S. violated its sovereignty by training, arming, and supporting the Contras, conducting military attacks, unauthorized overflights, and mining Nicaraguan waters.
The ICJ held that these acts breached Nicaragua’s sovereignty, violated the principle of non-intervention and the prohibition on the use of force, and also breached the Treaty of Friendship, Commerce, and Navigation. The Court ordered the U.S. to cease the illegal acts and make reparations.
🥜 Backing rebels, attacking territory, or mining waters violates sovereignty and the ban on force—State power stops where another State’s sovereignty begins.
Doctrine of Self-Determination
The Doctrine of Self-Determination affirms that peoples—not governments—have the right to choose their political status and to pursue their economic, social, and cultural development.
It is a cornerstone of decolonization and is recognized under the UN Charter and the International Covenant on Civil and Political Rights. In international law, self-determination has erga omnes character—meaning it is owed to the international community as a whole, not just to a specific State.
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High-yield in Public International Law, often tested alongside state sovereignty, territorial integrity, use of force, and jurisdiction of international courts. A recurring trap is assuming that recognition of an erga omnes right automatically gives courts jurisdiction—it does not.
East Timor
(Portugal v. Australia), ICJ Reports 1995.
Portugal challenged a treaty between Australia and Indonesia allowing joint exploitation of Timor Sea resources, arguing it violated the right of the people of East Timor to self-determination while the territory was under Indonesian occupation.
Although the ICJ affirmed that self-determination is an erga omnes right, it dismissed the case for lack of jurisdiction, holding that deciding Australia’s responsibility would necessarily require ruling on Indonesia’s legal rights and conduct, even though Indonesia had not consented to the Court’s jurisdiction. Applying the Monetary Gold principle, the Court refused to proceed.
🥜 Even when a right is erga omnes (like self-determination), the ICJ cannot rule if doing so would determine the rights of a non-consenting third State.
Doctrine of State Immunity
The Doctrine of State Immunity means a State cannot be sued in the courts of another State without its consent.
The key distinction is the nature of the act: immunity applies to sovereign/governmental acts (jure imperii), but not to commercial or proprietary acts (jure gestionis). Philippine courts apply this doctrine as part of international comity and respect for sovereign equality.
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Holy See v. Rosario, Jr., G.R. No. 101949, December 1, 1994 (Supreme Court; Lawphil).
A civil suit was filed against the Holy See over a lease of property used as a diplomatic residence. The Supreme Court dismissed the case, holding that the Holy See is a sovereign entity with international juridical personality and enjoys state immunity, because the lease was sovereign in character (jure imperii), not a commercial transaction.
🥜 A sovereign State (or entity) is immune from suit for sovereign acts; immunity is lost only when the act is commercial (jure gestionis).
🚨 Bar Trap:
Do not confuse state (sovereign) immunity with diplomatic immunity—the former protects the State/entity, the latter protects individual diplomats.
Doctrine of Non-Intervention
The Doctrine of Non-Intervention bars States from coercively interfering in the internal or external affairs of other States—especially through force, armed support, or political coercion.
Anchored in Article 2(4) of the UN Charter, it protects sovereignty and political independence. While diplomacy and lawful collective action exist, unilateral interference—direct or indirect—crosses the line.
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High-yield in Public International Law. Frequently tested with use of force vs. non-intervention, proxy warfare, support to rebels, and the trap that “indirect” assistance (funding, training, arming) is permissible—it isn’t.
Military and Paramilitary Activities in and against Nicaragua
(Nicaragua v. United States), ICJ Reports 1986.
Nicaragua challenged U.S. support for the Contras and operations affecting its territory. The ICJ held that arming, training, and financing rebel forces constitutes unlawful intervention and violates the prohibition on the use of force and non-intervention, even without a formal declaration of war.
🥜 Backing rebels—directly or indirectly—breaches non-intervention and the ban on force; coercion by proxy is still illegal.
Doctrine of Jus Cogens (Peremptory Norms)
Jus cogens norms are peremptory rules of international law that sit at the very top of the legal hierarchy.
They are non-derogable—no State may violate them, and no treaty, agreement, or domestic law can justify an exception.
Classic examples include the prohibitions against genocide, slavery, torture, crimes against humanity, and aggression. If a rule or treaty conflicts with a jus cogens norm, it is void.
⚡⚡⚡ High-yield in Public International Law. Frequently tested in questions on treaty validity, state responsibility, use of force, and human rights.
A common trap is assuming State consent or treaty obligations can override jus cogens—they cannot.
Case Concerning Armed Activities on the Territory of the Congo
(Democratic Republic of the Congo v. Uganda), ICJ Reports 2005.
The ICJ found Uganda internationally responsible for unlawful use of force, occupation, and serious human rights violations committed in the DRC. The Court emphasized that acts amounting to aggression and grave human rights abuses violate fundamental norms of international law, and no military necessity or political justification can excuse such conduct.
🥜 Violations of jus cogens—like aggression and serious human rights abuses—are never legally justifiable, regardless of consent, necessity, or treaty claims.
Doctrine of the Responsibility to Protect (R2P)
The Responsibility to Protect (R2P) doctrine holds that sovereignty is not a shield for mass atrocities.
When a State is unable or unwilling to protect its population from genocide, war crimes, ethnic cleansing, or crimes against humanity, the international community has a responsibility to step in—starting with diplomatic and humanitarian measures, and, as a last resort, collective action through the UN Security Council.
R2P reframes sovereignty as responsibility, not absolute control.
⚡⚡ Medium–High yield in Public International Law. Commonly tested in problems involving humanitarian intervention, use of force, UN Security Council authority, and the limits of non-intervention. A frequent trap is assuming unilateral military action is allowed under R2P—it is not; Security Council authorization is key.
United Nations Security Council Resolution 1973 (2011) – Libya (Official UN Documents).
In response to mass violence against civilians under the Gaddafi regime, the UN Security Council invoked R2P and authorized member States to take “all necessary measures” to protect civilians, including the establishment of a no-fly zone. This marked the first major operational use of R2P to justify collective military action aimed at civilian protection rather than regime change.
🥜 R2P allows collective international action—authorized by the UN Security Council—when a State fails to protect its people from mass atrocities.
Universal Jurisdiction
The Doctrine of Universal Jurisdiction allows a State to prosecute certain grave international crimes no matter where they were committed, and regardless of the nationality of the offender or victim.
It applies only to the most serious offenses under international law—genocide, war crimes, crimes against humanity, and torture—because these crimes are considered offenses against the international community as a whole.
The doctrine reflects the idea that some acts are so egregious that no safe haven should exist for perpetrators.
⚡⚡⚡ High-yield in Public International Law. Frequently tested alongside state immunity, diplomatic immunity, head-of-state immunity, and limits on jurisdiction. A classic trap is assuming universal jurisdiction automatically overrides immunity—it does not.
In re: Request of the Westinghouse Electric Corporation for Judicial Assistance, G.R. No. 75885, February 12, 1987 (Supreme Court; Lawphil).
The case primarily involved judicial assistance related to alleged corruption during the Marcos regime. While not a direct prosecution under universal jurisdiction, the decision is often cited for recognizing the international community’s shared interest in accountability for serious transnational and international offenses, reinforcing the idea that some crimes implicate concerns beyond purely domestic jurisdiction.
🥜 Certain serious offenses implicate international accountability, but jurisdiction must still rest on a recognized legal basis.
Arrest Warrant of 11 April 2000
(Democratic Republic of the Congo v. Belgium), ICJ Reports 2002.
Belgium issued an arrest warrant against the sitting Foreign Minister of the DRC under its universal jurisdiction law for alleged war crimes. The ICJ held that even where universal jurisdiction is recognized, incumbent foreign ministers enjoy immunity from criminal jurisdiction of foreign states while in office.
🥜 Universal jurisdiction exists—but it does not override immunity of sitting high-ranking state officials under international law.
Doctrine of Diplomatic Immunity
The Doctrine of Diplomatic Immunity protects foreign diplomats from the criminal and civil jurisdiction of the host State, allowing them to perform official functions without intimidation or interference. The doctrine is grounded in the Vienna Convention on
Diplomatic Relations (1961) and applies not as a personal privilege, but as a functional necessity for effective diplomatic relations. In the Philippines, once diplomatic status is recognized, local courts must respect the immunity unless it is expressly waived by the sending State.
⚡⚡⚡ High-yield in Public International Law and Political Law. Frequently tested in problems involving criminal liability of diplomats, jurisdictional conflicts, waiver of immunity, and treaty obligations vs. local police power.
A common trap is assuming immunity depends on the gravity of the offense—it does not.
Minucher v. Court of Appeals, G.R. No. 142396, February 11, 2003 (Supreme Court; Lawphil).
Minucher involved an Iranian national officially recognized as a diplomatic agent who was charged in the Philippines for acts allegedly committed in his private capacity.
The Supreme Court upheld his claim of diplomatic immunity, ruling that under the Vienna Convention on Diplomatic Relations, diplomats are immune from criminal jurisdiction of the receiving State, and Philippine courts must dismiss proceedings absent a clear waiver of immunity by Iran.
🥜 Once diplomatic status is recognized, Philippine courts have no jurisdiction—diplomatic immunity applies unless expressly waived by the sending State.
Doctrine of Incorporation
The Doctrine of Incorporation means that generally accepted principles of international law automatically form part of Philippine law, even without a separate statute.
This is expressly stated in Article II, Section 2 of the 1987 Constitution, allowing courts to directly apply customary international law—especially norms on human rights, humanitarian law, and state responsibility—without waiting for Congress to act.
⚡⚡⚡ High-yield in Public International Law and Political Law. Commonly tested in questions on customary international law vs. treaties, war crimes and humanitarian law, and traps assuming that all international rules need legislative transformation (they don’t—only treaties usually do).
Kuroda v. Jalandoni, G.R. No. L-2662, March 26, 1949 (Supreme Court; Lawphil).
Kuroda, a Japanese general charged with war crimes, challenged the jurisdiction of the Philippine military tribunal, arguing that the Philippines had not enacted a law penalizing war crimes. The Supreme Court rejected this, holding that generally accepted principles of international law—such as the laws of war and the Geneva Conventions—are part of Philippine law by incorporation, providing a valid legal basis for prosecution even without a specific statute.
🥜 Customary international law applies directly in the Philippines—courts may enforce humanitarian norms even without implementing legislation.
Doctrine of Transformation
The Doctrine of Transformation, holds that international law does not automatically apply domestically.
Treaties and international conventions must first be transformed into Philippine law through constitutional processes—typically Senate concurrence and, when required, implementing legislation—before courts can enforce them. In short: international commitments bind the State externally, but they do not create enforceable rights internally unless properly adopted.
⚡⚡⚡ High-yield in Public International Law and Political Law. Frequently tested through treaty vs. domestic law conflicts, Senate concurrence questions, and traps assuming that ratified conventions automatically override statutes or create judicially enforceable rights without legislation.
MeTC Judge Caesar O. Buenagua v. Court of Appeals and Ma. Ludivina P. Tangcangco, G.R. No. 178063, April 6, 2011 (Supreme Court; Lawphil).
The issue involved reliance on international conventions—specifically the Vienna Convention on Diplomatic Relations—as a direct basis for judicial action.
The Supreme Court ruled that international conventions cannot be applied by Philippine courts unless they have been transformed into domestic law through the proper constitutional process. Mere existence or ratification of an international convention does not make it self-executing or automatically enforceable locally.
🥜 International law binds the Philippines internationally, but domestically it applies only after proper transformation through constitutional and legislative processes.
Doctrine of Pacta Sunt Servanda
The Doctrine of pacta sunt servanda means treaties must be kept. Once a State validly enters into a treaty, it is legally bound to perform its obligations in good faith and cannot casually walk away just because compliance becomes inconvenient.
This principle is a backbone of international law and explains why treaty commitments can limit domestic discretion, especially in areas like extradition, trade, and human rights.
⚡⚡⚡ High-yield in Public International Law and Political Law—often tested in treaty enforcement, extradition, executive vs. Senate concurrence issues, and claims that domestic law excuses treaty breach.
A classic trap is arguing that internal law or policy can justify non-compliance with a valid treaty.
Government of Hong Kong Special Administrative Region v. Olalia, Jr., G.R. No. 153675, April 19, 2007 (Supreme Court; Lawphil).
The case arose from an extradition request by Hong Kong under an existing extradition agreement. The Supreme Court held that the Philippines is bound to honor its treaty commitments in good faith, stressing that under pacta sunt servanda, the State cannot refuse compliance with an extradition treaty absent a valid legal basis.
🥜 Once the Philippines enters into a treaty, it must comply in good faith—treaty obligations cannot be ignored by invoking domestic convenience or discretion.
Gabčíkovo–Nagymaros Project
(Hungary v. Slovakia), ICJ Reports 1997.
Hungary unilaterally suspended and later abandoned its treaty obligations on a joint dam project with Slovakia, citing necessity and environmental concerns.
The ICJ rejected the unilateral suspension, reaffirming that treaties remain binding and may be suspended or terminated only under conditions recognized by international law.
🥜 States cannot unilaterally suspend or abandon treaties—pacta sunt servanda requires performance unless international law clearly allows otherwise.
The Principle of Non-Refoulement
The principle of non-refoulement bars a State from returning, deporting, or expelling a person to a country where they face a real risk of persecution, torture, or serious harm.
It originates from the 1951 Refugee Convention and is now widely accepted as a core norm of international human rights and refugee law. In the Philippines, this principle applies through constitutional commitments to human rights and adherence to international law, limiting the government’s power to deport when life or liberty is at stake.
⚡⚡ Medium–High yield in Public International Law and Political Law—often tested in scenarios involving deportation, extradition, immigration discretion, and treaty obligations vs. executive power. A common trap is assuming deportation is purely discretionary even when persecution risk is shown.
Commissioner of Immigration v. Go Teh, G.R. No. 147571, October 25, 2001 (Supreme Court; Lawphil).
Go Teh, a Chinese national, faced deportation despite alleging risk of persecution if returned. The Supreme Court halted the deportation, applying non-refoulement and holding that immigration powers are not absolute when credible threats to life or freedom exist.
The Court recognized that the Philippines must not deport individuals to places where they may be persecuted, consistent with international obligations and constitutional human rights protections.
🥜 The State cannot deport a person to a country where they face persecution—immigration discretion yields to non-refoulement and human rights.
Doctrine of Territorial Integrity
The Doctrine of Territorial Integrity means a State’s borders are not up for grabs—they cannot be changed by force or unilateral action. Once boundaries are recognized under international law, other States must respect them. The doctrine protects stability, sovereignty, and peaceful relations by freezing borders against armed pressure or coercion.
⚡⚡ Frequently tested in Public International Law when exam questions involve use of force, boundary disputes, secession claims, or self-determination vs. sovereignty—the usual trap is justifying border changes through force or “historical claims.”
Case Concerning the Frontier Dispute
(Burkina Faso v. Mali), ICJ Reports 1986.
After clashes over an undefined colonial-era boundary, Burkina Faso and Mali asked the ICJ to determine their frontier. The Court upheld territorial integrity by applying uti possidetis juris, fixing borders based on pre-independence administrative lines and rejecting any attempt to alter boundaries through force or post-independence claims.
🥜 Recognized borders—especially those inherited at independence—cannot be changed by force; uti possidetis locks them in to preserve stability.
Note: The decision is international in scope; its principles guide domestic application when courts assess sovereignty, boundary claims, or the legality of force-related actions consistent with international law.
Doctrine of International Humanitarian Law (IHL)
International Humanitarian Law (IHL), also known as the law of war or the law of armed conflict, seeks to limit the effects of armed conflict by protecting those who are not participating in hostilities (civilians) and restricting the means and methods of warfare. The Geneva Conventions are central to this doctrine.
International Committee of the Red Cross v. Sandiganbayan (Philippines, 1991)
This case affirmed the immunity of the International Committee of the Red Cross (ICRC) in the Philippines due to its role in upholding international humanitarian law.
Right to a Clean and Healthy Environment (Customary International Law)
Right to a Balanced and Healthful Ecology (Art. II, Sec. 16)
Core Right
The State has a constitutional duty to protect and advance the right of the people to a balanced and healthful ecology.
Nature of the Right
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Self-executing (not merely aspirational)
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Intergenerational (enforceable for future generations)
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Rooted in human life, health, and sustainability
International Law Link
Informed by customary international law, including:
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Precautionary Principle – act to prevent harm despite scientific uncertainty
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Polluter-Pays Principle – polluters bear environmental costs
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No-Transboundary Harm Rule – states must not cause environmental harm beyond their borders
Judicial Tools
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Intergenerational standing
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Writ of continuing mandamus
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Direct judicial enforcement against State inaction
Typical Bar Angles
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Article II provision: policy vs. enforceable right
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Environmental protection vs. economic activity
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Standing of minors / citizens
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Continuing mandamus vs. ordinary mandamus
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Application of international environmental principles in domestic law
⚡⚡⚡ Consistently tested in Political Law and PIL cross-overs—watch for traps treating Article II, Sec. 16 as non-justiciable despite settled jurisprudence declaring it actionable.
Oposa v. Factoran, G.R. No. 101083, 30 July 1993 (Supreme Court; Lawphil)
🥜 The right to a balanced and healthful ecology is self-executing and intergenerational, allowing minors to sue on behalf of future generations.
MMDA v. Concerned Residents of Manila Bay, G.R. Nos. 171947-48, 18 December 2008 (Supreme Court; Lawphil)
🥜 Courts may issue a writ of continuing mandamus to compel government agencies to perform their ongoing constitutional duty to protect the environment.
Resident Marine Mammals of the Protected Seascape Tañon Strait v. Reyes, G.R. No. 180771, 21 April 2015 (Supreme Court; Lawphil)
🥜 Under the precautionary principle, environmental protection prevails even when scientific certainty about harm is incomplete.
Treaties & Conventions
Treaties are formal, legally binding agreements between two or more sovereign states or international organizations.
They are negotiated and signed by authorized representatives and usually require ratification before they take effect domestically. Treaties can deal with a wide range of matters—trade, defense, environment, and human rights—and are governed by international law, most notably the Vienna Convention on the Law of Treaties (1969).
Conventions are a type of treaty, but they usually function as framework agreements. They set out general standards or norms on broad issues and leave the details of implementation to the States, often requiring domestic legislation to give them full effect.
While conventions are legally binding once ratified, they are typically more flexible in application. A common example is the Convention on the Rights of the Child (CRC).
⚡⚡ Frequently tested in Public International Law through questions distinguishing form vs. function—watch for traps where the bar asks whether a convention is binding (it is, once ratified) or whether a treaty automatically applies domestically (it does not, without proper incorporation).
How Countries Enter Into Treaties
Treaty-making follows a predictable sequence, even if domestic requirements differ across states. For bar purposes, remember the core stages and where legal effect actually begins.
1. Negotiation
States (through diplomats or authorized officials) discuss, draft, and revise treaty terms until consensus is reached.
👉 No legal obligation yet—this is purely diplomatic.
2. Signature
Authorized representatives sign the treaty, signaling intent to be bound.
👉 Still not legally binding by itself.
3. Ratification
Each state completes its domestic approval process (e.g., legislative concurrence).
👉 This is the critical step where consent becomes binding under international law.
4. Deposit
The ratified treaty is formally deposited with a designated depository (often the UN).
👉 Confirms official acceptance and triggers treaty effects where required.
5. Domestic Implementation
How the treaty applies internally depends on the legal system:
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Dualist states → need enabling legislation
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Monist states → treaty may apply directly upon ratification
Who Represents the State?
Treaties are negotiated and signed by authorized state agents—typically heads of state, foreign ministers, ambassadors, or subject-matter experts—depending on the treaty’s scope and importance.
Treaties vs. Conventions
Similarities
Both involve:
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Negotiation
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Signature
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Ratification
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Domestic implementation (monist vs. dualist)
👉 Same legal pipeline, same international-law foundation.
Key Differences
Purpose & Scope
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Treaties → specific, often bilateral or limited-party agreements
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Conventions → broader, usually multilateral frameworks (e.g., human rights, environment)
Adoption Process
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Treaties → negotiated by specific states
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Conventions → often adopted in international conferences with voting or consensus
Implementation & Monitoring
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Conventions often include monitoring bodies, reporting duties, or follow-up protocols
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Treaties usually do not
⚡⚡ Medium–High yield in Public International Law. Frequently tested through distinctions between signature vs. ratification, international obligation vs. domestic enforceability, and treaty vs. convention traps—especially in questions involving **Senate concurrence
Bayan v. Zamora, G.R. No. 138570, 10 October 2000 (Supreme Court; Lawphil)
The validity of the Visiting Forces Agreement (VFA) was challenged for allegedly lacking proper treaty status and Senate concurrence. The Court upheld the VFA, ruling that Senate concurrence satisfied the constitutional requirement and that the agreement was valid both internationally and domestically, even if denominated differently by the parties.
🥜 What matters is Senate concurrence—not the label—once concurred in, a treaty binds the Philippines internationally and domestically.
Pimentel v. Executive Secretary, G.R. No. 158088, 6 July 2005 (Supreme Court; Lawphil)
Petitioners questioned the Philippines’ signing of the Rome Statute of the International Criminal Court (ICC) without Senate concurrence. The Court held that signature alone does not bind the State; only ratification with Senate concurrence creates international obligations.
🥜 Signature signals intent; ratification with Senate concurrence creates binding international obligation.
Saguisag v. Ochoa, G.R. Nos. 212426 & 212444, 12 January 2016 (Supreme Court; Lawphil)
The Enhanced Defense Cooperation Agreement (EDCA) was challenged for lack of Senate concurrence. The Court ruled that EDCA is an executive agreement implementing existing treaties (VFA, MDT) and did not require separate Senate concurrence.
🥜 Executive agreements that merely implement existing treaties need no new Senate concurrence.
Abaya v. Ebdane, G.R. No. 167919, 14 February 2007 (Supreme Court; Lawphil)
The case involved a foreign-funded infrastructure agreement and whether it required Senate concurrence. The Court clarified that not all international agreements are treaties—many are executive agreements valid upon executive action alone.
🥜 Only treaties need Senate concurrence; executive agreements may bind the State without it.
Pharmaceutical and Health Care Association of the Philippines v. Duque III, G.R. No. 173034, 9 October 2007 (Supreme Court; Lawphil)
Petitioners argued that international commitments
required legislative enactment to be enforceable. The Court reiterated that in a dualist system, treaties generally require implementing legislation to be enforceable domestically unless self-executing.
🥜 International obligations do not automatically become enforceable domestic law without proper incorporation.
Bar Synthesis (How the Examiner Thinks)
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Signature ≠ ratification (Pimentel)
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Senate concurrence is constitutionally decisive (Bayan)
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Executive agreements are valid if they implement existing treaties (Saguisag, Abaya)
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International obligation ≠ domestic enforceability (PHAP v. Duque)
⚡⚡ These cases are Medium–High yield and often tested together—watch for label traps, missing Senate concurrence, and assumptions that international law automatically applies domestically.