Paragraph 4 of Article 20 shows that the Vienna Convention contains a rigid principle of unanimous acceptance of reservations.
It reads "The acceptance of a reservation by another contracting State of the reserving State a party to the treaty in relation to that other State if the treaty is in effect or when it comes into force for those States" and Article 20 paragraph 4 c) reads "An act expressing the consent of a State to be bound by the treaty and containing a reservation is effective as soon as, at least one other, contracting State has accepted the reservation." To better understand the change that is introduced by these two articles, one must relinquish the principle of unanimous acceptance of reservations.
The expansion of international society prompted him to look for rules that can be applied universally. This development was triggered off by the reservations that had been made by the Soviet Union to the Convention on the Prevention and Punishment of the Crime of Genocide. When consulted by the General Assembly of the United Nations, the International Court of Justice ruled (in 1951) that in its opinion the principle of unanimous acceptance was not absolute.
This relaxation, however, led to turmoil in international society which was reflected in the preparatory work for the Vienna Convention. Some states were in favor of maintaining the principle of unanimous acceptance.
There was one reporter who enabled the International Court of Justice to change their position in favor of abandoning the principle of unanimous acceptance. It should be noted that the Commission has distinguished the first multilateral treaty to which the principle of unanimous acceptance was abandoned and the plurilateral treaties which remained subject to the principle of unanimous acceptance.
Rules form the Vienna Convention and also show great flexibility for the reserving State and promote the access of many States to the treaty. Indeed, paragraph 5 of Article 20 provides that there may be an implicit acceptance of the reservation. However, some states, including the U.S., have asked about this article which has been extensively discussed within the Commission. If a State is presumed to be bound by a new treaty and a relationship that it never explicitly approves of. According to the United States Government, the State has no objection that to its denial of the opportunity to prevent participation in the Treaty of the State which formulated the reservation.
The Vienna Convention did make some exceptions to the general rule that a reserving State becomes party to a treaty from the moment that the State accepts it.
There were some exceptions that the International Court of Justice had not foreseen in 1951. The first is that of Article 20 paragraph 2.
[...] − COMBACAU "Logic of the validity of enforceability against logic in the Vienna Convention on the Law of Treaties", in M. Mixtures virally, Paris, Pedone p. 195-203. − COMBACAU and ON International law, Paris − United Nations Human Rights Committee, "General Comment No of 4 November 1994 on issues relating to reservations made upon ratification of the Covenant or the Optional Protocols or membership these instruments, or in relation to declarations under article 41 of the Covenant "(full text), RUDH 1995, pp. [...]
[...] Paragraph is, meanwhile, the case of dumb treaties on the issue of reservations (which is also the case of the Vienna Convention itself) and provides that in this case, states must make reserves compatible with the object and purpose of the treaty. In this article the Vienna Convention has simply taken the condition which had been cleared by the ICJ in its opinion of 1951. For this condition, the ICJ had wanted to preserve the integrity of the Treaty and was thus rejected the argument too proactive consisting of accept any reservation. [...]
[...] The conditions of admissibility of reservations of the Vienna Convention A. The end of the theory of the unanimous acceptance of reservations These are Articles 20, paragraph 4 and which clearly shows that the Vienna Convention abandon the rigid principle of unanimous acceptance of reservations. Article 20 paragraph is in fact as follows: "The acceptance of a reservation by another author of the Contracting State is a State Party to the reserve treaty in relation to that other State if the treaty is in effect or when it comes into force for those States and Article 20, paragraph 4 reads: "An act expressing the consent of a State to be bound by the treaty and containing a reservation is effective as soon as at least one other contracting State has accepted the reservation." To better understand the changes introduced by these two articles, we must return to the principle of unanimous acceptance of reservations. [...]
[...] Paragraph provides expressly prohibit reservations, paragraph allows for the implication. With this freedom, the practice of States in respect of reservations is extremely diverse: from an explicit clause states can prohibit making reservations (eg the Rio Conventions and New York on biodiversity and climate change) certain conventions implicitly prohibit reservations due to their mission (eg ILO conventions due to their mission of standardization of working conditions in the world), others are content to treaties prohibit reservations to certain of their provisions which amounts to implicitly allow for others or prohibit certain types of reserves (eg the prohibition of "general reserves" in the European Convention for the Protection of human Rights and Fundamental Freedoms or conversely expressly authorizes reservations to specific provisions which amounts to ban for others. [...]
[...] Some states were also in favor of maintaining the principle of unanimous acceptance. It is the rapporteur Waldock that changed the ICJ's position definitively in favor of abandoning the principle of unanimous acceptance. It should be noted that the Commission distinguished first multilateral treaties to which the principle of unanimous acceptance was abandoned and plurilateral treaties remained subject to the principle of unanimous acceptance. This distinction has been abandoned in the Vienna Convention, which provides that it is enough now only one State accepts a reservation for the reserving State becomes a party to the treaty, and thus completely reverses the rigid regime that emerged from the League. [...]
using our reader.