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:

• Dualist states → need enabling legislation

• 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:

• Negotiation

• Signature

• Ratification

• Domestic implementation (monist vs. dualist)

👉 Same legal pipeline, same international-law foundation.

Key Differences

Purpose & Scope

• Treaties → specific, often bilateral or limited-party agreements

• Conventions → broader, usually multilateral frameworks (e.g., human rights, environment)

Adoption Process

• Treaties → negotiated by specific states

• Conventions → often adopted in international conferences with voting or consensus

Implementation & Monitoring

• Conventions often include monitoring bodies, reporting duties, or follow-up protocols

• Treaties usually do not

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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)

• Signature ≠ ratification (Pimentel)

• Senate concurrence is constitutionally decisive (Bayan)

• Executive agreements are valid if they implement existing treaties (Saguisag, Abaya)

• 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.