Treaty of Accession

How It Works

When a state seeks to join an existing international treaty, it does so through a formal agreement known as a Treaty of Accession. This process involves the state accepting all the rights, obligations, and conditions outlined in the original treaty without renegotiating its terms. Essentially, accession allows a new party to become bound by the treaty as if it had been an original signatory.

The procedure typically requires the acceding state to deposit an instrument of accession with a designated entity, often a treaty depositary like the United Nations Secretary-General or a specific international organization. Once accepted, the state gains the same legal status and responsibilities under the treaty as the original parties.

Why It Matters

Treaties often establish frameworks for cooperation on issues such as trade, security, environmental protection, or human rights. When new states accede, they expand the treaty's reach and effectiveness, promoting wider international collaboration and legal uniformity.

Without the mechanism of accession, states wishing to join an existing treaty would have to negotiate new agreements from scratch, a process that would be inefficient and could undermine the stability of international law. Accession thus provides a straightforward and standardized path for expanding treaty membership.

Treaty of Accession vs Treaty Ratification

While accession and ratification both result in a state becoming bound by a treaty, they differ in timing and context. Ratification applies to treaties a state has signed; it is the formal confirmation, often involving domestic approval processes, that makes the treaty legally binding for that state.

Accession, on the other hand, is used when a state did not sign the treaty during the original negotiation phase but wishes to join later. It skips the signature step and directly binds the state to the treaty terms upon depositing the accession instrument.

Real-World Examples

A notable example is the accession of the United States to the Rome Statute of the International Criminal Court, which it never signed but could have joined through accession. Another case is the European Union treaties, where new member states accede to existing treaties to become part of the EU legal framework.

In the context of human rights, countries often accede to conventions like the Convention on the Elimination of All Forms of Discrimination Against Women (CEDAW) after the initial adoption, signaling their commitment to international norms.

Common Misconceptions

One misunderstanding is that accession allows a state to modify treaty terms. In reality, accession requires full acceptance of the treaty as it stands; modifications would require renegotiation or reservations if permitted.

Another misconception is that accession is a quick or informal process. While it streamlines joining a treaty, accession often involves significant domestic legal review and political consideration before the instrument is deposited.

Finally, some believe accession applies only to multilateral treaties. However, it can also apply to bilateral treaties, though it is more common in multilateral contexts due to the collective nature of such agreements.