“For the Sake of All Mankind, to Exclude Completely the Possibility of the Use of Chemical Weapons”: Assessing the Impact of the (Non)-Use of the CWC Challenge Inspection Mechanism on Small-Scale Chemical Weapons Attacks in Ukraine

Abstract

The 1993 Chemical Weapons Convention outlines various mechanisms and procedures for addressing issues of non-compliance by States Parties. However, one mechanism often seen as the most aggressive form of investigation, the challenge inspection, has never been put to use – I argue that this is because the mechanism has historically been seen as too drastic, technically complicated, and politically polarizing. At the same time, the global community has witnessed an emergence of small-scale chemical weapons use in the past fifteen years, which has not been addressed through the challenge inspection mechanism. Instead, these small-scale uses have been investigated through ad hoc mechanisms and other clarification procedures under the Convention. This thesis focuses empirically on four case studies: the 2013 accession of Syria to the CWC and its subsequent violation of the Convention, the 2018 poisoning of the Skripals in the United Kingdom, the 2020 poisoning of Alexei Navalny in Russia, and the 2022-2025 use of chemical weapons on the battlefield in Russia’s invasion of Ukraine. In this thesis, I will argue that the disparity in the severity of compliance mechanisms under the CWC has encouraged small-scale use of chemical weapons from non-compliant states, who appear to have concluded that they will not be subject to a challenge inspection nor punished severely – the benefits of using small-scale chemical weapons outweigh the costs of any punishment they may or may not face. In turn, I demonstrate that this has weakened challenge inspections as investigative tools under the CWC and risks rendering the mechanism obsolete. Finally, I will discuss the implications of this small-scale use for the future of the non-use norm and the chemical disarmament regime more broadly. I will conclude by offering pathways forward, including through the suspension of certain rights of non-compliant States Parties, U.S. engagement with the Non-Aligned Movement, the reinvigoration of challenge inspection test exercises, and relevant amendments to the CWC.