Practice Relating to Rule 73. Biological Weapons
In its written statement submitted to the ICJ in the Nuclear Weapons case in 1995, Mexico noted
a series of international instruments … [which] led to a prohibition on the use of certain weapons. Such instruments included … the Protocol of 1925 for the prohibition of the use in war … of bacteriological methods of warfare (The Geneva Gas Protocol); and the Convention on the prohibition of the development, production and stockpiling of bacteriological (biological) and toxin weapons and their destruction of 10 April 1972, etc.
At the Fifth Review Conference of States Parties to the Biological Weapons Convention in 2001, Mexico stated: “The 1972 Convention broadens the provisions of the 1925 [Geneva Gas] Protocol and renders obsolete the reservations that had restricted the latter to an instrument of first use prohibition.” It encouraged “the States that have not yet done so to withdraw these reservations”. It also urged that the “goal must be to review and strengthen the compliance with the regime on the prohibition of biological weapons to protect nations and individuals from the risk of the possible use of weapons of mass destruction”.
In 2009, Mexico submitted a proposal to the UN Secretary General to amend Article 8(2)(c) of the 1998 ICC Statute in accordance with Article 121(1) of the Statute, stating:
Within the category of serious violations of the laws and customs applicable in international armed conflicts, the use of certain weapons whose effects are of an indiscriminate nature or cause superfluous injury or unnecessary suffering is included. Such weapons are: … b) asphyxiating, poisonous or other gases, and all analogous liquids, materials and devices … The use of these … kinds of weapons is prohibited by conventional and customary international law.
[footnotes in original omitted]