Reservation (law)

a unilateral statement, however phrased or named, made by a State, when signing, ratifying, accepting, approving or acceding to a treaty, whereby it purports to exclude or to modify the legal effect of certain provisions of the treaty in their application to that State. (Article 2 (1)(d))

In effect, a reservation allows the state to be a party to the treaty, while excluding the legal effect of that specific provision in the treaty to which it objects. States cannot take reservations after they have accepted the treaty; a reservation must be made at the time that the treaty affects the State. The Vienna Convention did not create the concept of reservations but codified existing customary law. Thus even States that have not formally acceded to the Vienna Convention act as if they had. As reservations are defined under the Vienna Convention and interpretative declarations are not, the two are sometimes difficult to discern from each other. Unlike a reservation, a declaration is not meant to affect the State's legal obligations but is attached to State's consent to a treaty to explain or interpret what the State deems unclear.

Procedure

The Articles 19–23 of the Vienna Convention details the procedures relating to reservations. To see if a reservation is valid the legality of the reservation test applies as described in article 19 of the Vienna Convention. According to this article a state may not formulate a reservation if:

1: The reservation is prohibited by the treaty. (e.g. the Supplementary Convention on the Abolition of Slavery, Convention against Discrimination in Education and Minamata Convention on Mercury)
2: The treaty provides that only specified reservations, which do not include the reservation in question, may be made.

This is often the case when during negotiations it becomes apparent that a certain provision in a treaty will not be agreed upon by all parties. Therefore, the possibility is given to parties not to agree with that provision but to agree with the treaty in general.

3: In cases not falling under (1) or (2), the reservation is incompatible with the object and purpose of the treaty.

Point 3 is called the compatibility test and is difficult to determine. It is not always clear what the object and purpose of the treaty is, especially when treaties are long and complex.

A reservation must be put into writing and then sent to either the depository of the treaty, in the case of a multilateral treaty, or directly to the other States party to the treaty.

A State may withdraw a reservation at any time. This requires written submission to the other signatory States.

Objections

When states make an objection to a reservation stating that it failed the legality test, there are three possible results, according to legal commentators:

1. The state which made the reservation is not bound by the treaty anymore. In other words, the state is no longer a party to this treaty.
2. The state which made the reservation is bound by the treaty including the parts on which it made the reservation.
3. The state which made the reservation is bound by the treaty, but not by the part on which it made the reservation.

There are many opponents to the second option who argue that this goes against the principle of state consent. States can only be bound by provisions they have consented to. Since they have made a reservation to a certain provision, they cannot be bound by it.

According to some commentators, what happens in practice in the VCLT regime is the third option. What follows from article 20 paragraph 4(b) and article 21 paragraph 3 VCLT is that the only thing which can happen is, that if an objecting state feels very strongly about a reservation, it will state that the whole treaty is not in effect between the reserving state and itself. This rarely happens, thus the reservation stands, whether it passed the legality test or not.

Others think differently on this. According to Anthony Aust, “if one or more contracting states have objected to the reservation as being prohibited, the reserving state must decide whether or not it is prepared to be a party without the reservation; and until it has made its position clear it cannot be regarded as a party”.

The difference of opinion on this is the fact that it is not likely that the articles 20 and 21 apply to reservations, which cannot to be made according to article 19 of the VCLT. However, they are applied in practice.

Example

Perhaps the most famous and controversial reservations are those taken by the United States when it signed the Convention on the Prevention and Punishment of the Crime of Genocide in 1986. The reservations taken were:

(1) That with reference to article IX of the Convention, before any dispute to which the United States is a party may be submitted to the jurisdiction of the International Court of Justice under this article, the specific consent of the United States is required in each case.
(2) That nothing in the Convention requires or authorizes legislation or other action by the United States of America prohibited by the Constitution of the United States as interpreted by the United States.

The second reservation may be interpreted as a statement that the national Constitution overrides any treaty obligations — a position mandated by a 1957 U.S. Supreme Court decision, Reid v. Covert. Under reciprocity, the United States cannot submit a legal case to the ICJ unless the other State agrees and does not state that it violates its national constitution.

Several nations expressed dismay and disapproval at the reservations, stating that it essentially made the treaty toothless. The responses included:

The Government of Ireland is unable to accept the second reservation made by the United States of America on the occasion of its ratification of the [said] Convention on the grounds that as a generally accepted rule of international law a party to an international agreement may not, by invoking the terms of its internal law, purport to override the provisions of the Agreement.

As concerns the first reservation, the Government of the Kingdom of the Netherlands recalls its declaration, made on 20 June 1966 on the occasion of the accession of the Kingdom of the Netherlands to the Convention […] stating that in its opinion the reservations in respect of article IX of the Convention, made at that time by a number of states, were incompatible with the object and purpose of the Convention, and that the Government of the Kingdom of the Netherlands did not consider states making such reservations parties to the Convention. Accordingly, the Government of the Kingdom of the Netherlands does not consider the United States of America a party to the Convention. […]

As the Convention may come into force between the Kingdom of the Netherlands and the United States of America as a result of the latter withdrawing its reservation in respect of article IX, the Government of the Kingdom of the Netherlands deems it useful to express the following position on the second reservation of the United States of America:

The Government of the Kingdom of the Netherlands objects to this reservation on the ground that it creates uncertainty as to the extent of the obligations the Government of the United States of America is prepared to assume with regard to the Convention. Moreover, any failure by the United States of America to act upon the obligations contained in the Convention on the ground that such action would be prohibited by the constitution of the United States would be contrary to the generally accepted rule of international law, as laid down in article 27 of the Vienna Convention on the law of treaties (Vienna, 23 May 1969)

The Government of the United Kingdom have consistently stated that they are unable to accept reservations to article IX. Accordingly, in conformity with the attitude adopted by them in previous cases, the Government of the United Kingdom do not accept the first reservation entered by the United States of America.
The Government of the United Kingdom object to the second reservation entered by the United States of America. It creates uncertainty as to the extent of the obligations which the Government of the United States of America is prepared to assume with regard to the Convention.