Modification of International Treaties

Modification of International Treaties

• Modification is the act or process of changing something to improve it or make it more acceptable
• Modification refers to altering or amending treaty terms without ending the treaty relationship
• States modify treaties when provisions require updating, revising, or changing due to evolving circumstances, new developments, or mutual consent
• The Vienna Convention on the Law of Treaties (VCLT) addresses issues related to amendments, reservations, and other matters relevant to the treaty modification process, but does not offer detailed rules on modification itself.

General Aspects

• No human agreement is intended to last forever; laws and treaties must adapt to changing times
• The main challenge in amending treaties is that consensual acts bind all parties. Amendments, as consensual acts, can only be modified with the consent of all parties. This gives each party a veto power regarding the amendment, at least for the effects of that amendment on that party.
• Rights under an older treaty remain valid as long as the treaty remains in force
• If some parties agree to a new treaty while others disagree, the result creates a divergence in rights and obligations impacting different parties
• Modifying agreements repeatedly can result in significant complexities and numerous treaty connections

Methods of Modification

• Modification can occur via bilateral or multilateral agreements, often involving negotiations to amend the original treaty.
• Modification can also occur through bilateral negotiations and mutual consent when involving only two parties
• Modifications of treaties including multiple parties may need agreement from all parties or a majority

Methods of Modification (continued)

• Express Agreement: Parties to the treaty explicitly agree to modify its terms; this is the most common and formal method.
• Implied Agreement: Modification inferred from the parties' consistent actions; this requires clear evidence of intent to modify and is less formal.
• Agreement by all Parties: All parties to the treaty must agree to the modification, regardless of the method used

Examples of Modification

• The Antarctic Treaty was modified through a series of protocols, including the Protocol on Environmental Protection
• The Biological Weapons Convention has been modified via declarations and resolutions of the states parties
• The World Trade Organization Agreements are subject to a complex modification procedure that involves negotiating and adopting protocols at the WTO Ministerial Conference

Ways of Modification

• There are two legal channels for modifying an agreement: informal modification by subsequent practice or formal modification through the adoption of revised versions
• After modification, the treaty remains valid and parties remain bound by the revised terms

Informal Modification

• Informal modification, also called “subsequent practice,” refers to modifying a treaty based on consistent actions over time. It indicates a mutual understanding to alter the terms but isn't expressly agreed to formally.
• This affects the interpretation of treaty provisions, not the specific text of the treaty itself
• For example, a treaty might specify fishing quotas. If both parties consistently exceed these limits without formal amendment, their actions could be interpreted as an informal modification of the treaty's provisions.
• The concept of self-defense in international law is based on evolving practice and has been adapted over time, including through use by international courts and significant developments in state behavior.

Formal Modification

• Formal modification alters treaties through the adoption of revised versions, achieved through negotiations, formal agreements, or amendments
• All treaty parties must agree to the modification.
• It's handled through a prescribed process, commonly involving negotiations, signature, and ratification
• Examples include: the amendment of the 1982 United Nations Convention on the Law of the Sea; the Canada-United States-Mexico Agreement (CUSMA); and the Kigali Amendment to the Paris Agreement regarding climate change

Special Rules in Institutional Treaties

• Institutional treaties have specific clauses to govern revisions. The aim is to define how the entire membership will be bound if revision is accepted.
• For example, the UN Charter's Article 108 establishes requirements for amending or revising the Charter. These processes must include specific vote thresholds and ratification criteria by member states.