Over the past week, two posts at Just Security have argued that the ICC can prosecute the use of chemical and biological weapons as a war crime, even though they — unlike other types of weapons — are not mentioned in Article 8 of the Rome Statute. The first post was written by Ralf Trapp, who argued as follows:
Furthermore, there are the provisions of the Rome Statute of the International Criminal Court (ICC). Even though it does not use the terminology of the CWC (“chemical weapons”), there is no doubt that the terms “employing poison or poisoned weapons” and “employing asphyxiating, poisonous or other gases, and all analogous liquid, materials or devices” found in the list of war crimes under the statute’s Article 8 would squarely apply to the use of chlorine or mustard gas as a weapon of war. Any such use would consequently come under the jurisdiction of the ICC.
Trapp does not even acknowledge any other interpretation of Article 8. By contrast, the second post, written by Alex Whiting, admits that a different interpretation is possible. But Whiting nevertheless sides with Trapp, citing an earlier post by Dapo Akande at EJIL: Talk!:
The Rome Statute originally included a direct ban on chemical and biological weapons, but it was dropped at the same time as a ban on weapons causing unnecessary suffering was narrowed to apply only to those weapons listed in an annex (which does not exist because the States Parties never adopted one). This narrowing was done to avoid having the broader provision apply to nuclear weapons. The direct chemical and biological weapons prohibition was then dropped, apparently because some negotiators thought that there should be parity in approach to nuclear weapons (possessed by wealthy nations) and chemical and biological weapons (the more likely option for poorer countries). The claim that that the Statute therefore does not cover chemical and biological weapons was reinforced by Belgium’s efforts at the ICC Review Conference in Kampala in 2010 to amend the Statute to include a ban on chemical and biological weapons, indicating that there was an understanding among at least some States Parties that the Statute as written did not already do so.
But Akande persuasively argues (reinforcing what Trapp intuits) that the language in the Statute prohibiting poisonous and asphyxiating gases and analogous liquids, materials, and devices plainly applies on its own terms to most — if not all — chemical and biological weapons. Since the treaty text is clearly written, there is no need to consider the history of its drafting, per the Vienna Convention on the Law of the Treaties. In this case, the difficulty with relying on the negotiation history in the first instance is that it is highly indeterminate: Assessing what 120 countries “intended” when they adopted the Rome Statute is nearly impossible, and therefore the plain language of the treaty should govern when it is clear, as it is here.
I disagree with Trapp and Whiting. I won’t rehash the arguments I made in response to Dapo’s post; interested readers can see our exchange in the EJIL: Talk! comments section. But I do want to flag three critical problems with the argument advanced by Trapp and Whiting: one factual, one theoretical, and one political.
The factual problem is that this is simply not a situation in which the drafting history is “highly indeterminate.” Few drafting disputes are as well known as the dispute over the criminalisation of nuclear weapons, chemical weapons, and biological weapons. And as Whiting’s own account makes clear, we know with absolute certainty that not enough states favoured criminalising the use of chemical and biological weapons — because the proposal to criminalise them failed. The reason why states opposed criminalising their use is irrelevant; I’m quite sure that some may have wanted to reserve the right to use them, while others were happy to criminalise their use but did not want to alienate the nuclear states. All that matters is that it is undisputed states tried and failed to criminalise the use of chemical and biological weapons.
It does not matter, then, whether “[a]ssessing what 120 countries ‘intended’ when they adopted the Rome Statute is nearly impossible.” What matters is whether we know how 120 states understood Art. 8 of the Rome Statute. And we do…