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Chloropicrin and its alleged use in the Ukrainian war (part 3)

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The first instalment of this four-part blog series reviewed the allegations of Russian chemical weapon (CW) use in the Ukrainian war from its start in 2014 until the present. At the meeting of the Executive Council of the Organisation for the Prohibition of Chemical Weapons (OPCW) in March 2024, the Ukrainian delegate reported 1,060 incidents since the Russian invasion in February 2022.

More recently, Ukraine claimed in a note verbale to the OPCW dated 13 June that it had recorded a total of 2,968 cases of Russian use of riot control agents (RCAs) between 15 February 2023 and 25 April 2024. It registered an additional 715 cases between 25 April and 24 May. 1,385 military personnel required medical treatment for chemical exposure, 215 of them in May. 82% of incidents involved K-51 and RG-Vo hand grenades. In May 2024, these munitions comprised 46% of the reported incidents. The note did not identify any other Russian munitions.

The second part summarised Russia’s alleged resort to chloropicrin. Schedule 3 of the Chemical Weapons Convention (CWC) lists this agent of First World War vintage. Consequently, no state party can hold

Ukrainian CW training exercise

it as an RCA. Ukrainian sources have reported only three incidents but without any corroborating evidence. No official Ukrainian statement or document to the OPCW mentions chloropicrin (except for one non-specific linkage with improvised explosive devices). Still, the claims cannot be dismissed out of hand. In April 1989, that is, before the breakup of the Soviet Union and the finalisation of the CWC negotiations, Soviet internal security and military units quelled civil unrest in Tbilisi, Georgia, with the same types of RCAs being mentioned today and chloropicrin.

The international press and commentators took note of the chloropicrin allegations after the US State Department mentioned the agent up front in a fact sheet on 1 May. It accepted the claims of RCA use and announced sanctions against Russian entities for their roles in violating the CWC. Five days earlier, the State Department had determined that Russia’s CW use violated international law under the Chemical or Biological Weapons (CBW) Act. It published the determination in the Federal Register on 7 June.

This third instalment analyses the US embrace of the chloropicrin claims. It concludes with a discussion of possible reasons for spotlighting the agent despite the lack of evidence in the public domain.

The US statement on Russian chloropicrin use

On 1 May 2024, the Office of the Spokesperson of the US Department of State issued a fact sheet, ‘Imposing New Measures on Russia for its Full-Scale War and Use of Chemical Weapons Against Ukraine’. Under the heading ‘Chemical and biological weapons activities and procurement’, it states:

The Department of State has made a determination under the CBW Act that Russia has used the chemical weapon chloropicrin against Ukrainian forces in violation of the Chemical Weapons Convention (CWC). We make this determination in addition to our assessment that Russia has used riot control agents as a method of warfare in Ukraine, also in violation of the CWC. The use of such chemicals is not an isolated incident, and is probably driven by Russian forces’ desire to dislodge Ukrainian forces from fortified positions and achieve tactical gains on the battlefield. Russia’s ongoing disregard for its obligations to the CWC comes from the same playbook as its operations to poison Aleksey Navalny and Sergei and Yulia Skripal with Novichok nerve agents.
In coordination with the Department of the Treasury, the Department of State is designating three Russian Federation government entities associated with Russia’s chemical and biological weapons programs and four Russian companies providing support to such entities. The Department of the Treasury is separately designating three entities and two individuals involved in procuring items for military institutes involved in Russia’s chemical and biological weapons programs, pursuant to a separate [Weapons of Mass Destruction] WMD non-proliferation authority.

The introductory section of the fact sheet, however, focusses entirely on chloropicrin:

The Department of State is concurrently delivering to Congress a determination pursuant to the Chemical and Biological Weapons Control and Warfare Elimination Act of 1991 (CBW Act) regarding Russia’s use of the chemical weapon chloropicrin against Ukrainian troops.

The Treasury Department announced nearly 300 new sanctions on the same day. Russia immediately denied the allegation.

This serious and formal accusation made headlines across the world. It also surprised the CBW expert community. As the summary of CW incidents in the first instalment of this blog series shows, most allegations in the Ukrainian war between February 2014 and May 2024 involve two lachrymatory agents, CS and CN. The Ukrainian note verbale to the OPCW of 13 June confirms this. The second instalment concluded that references to chloropicrin are sparse and mainly inaccurate or implausible.

The fact sheet also lacks specifics about where or how the Russian forces used chloropicrin. Publicly available resources make it hard to determine the origin or validate the substance of the US claim. Neither the OPCW nor any other international mechanism or humanitarian organisation are known to have launched investigations into chloropicrin use or published factual reports. In that sense, the US determination came out of the blue.

The legal framework for the US assertion

The State Department made the determination under national law, 22 US Code Chapter 65 – Control and Elimination of Chemical and Biological Weapons. According to §5604 of the CBW Act, the US President shall determine whether a foreign government ‘has used chemical or biological weapons in violation of international law or has used lethal chemical or biological weapons against its own nationals’ within 60 days of having received persuasive information from the executive branch.

On 7 June, the State Department published the public notice Determinations Regarding Use of Chemical Weapons by Russia Under the Chemical and Biological Weapons Control and Warfare Elimination Act of 1991 in the Federal Register:

Pursuant to sections 306(a), 307(a), and 307(d) of the Chemical and Biological Weapons Control and Warfare Elimination Act of 1991 (22 USC 5604(a), 5605(a), and 5605(d)), on 25 April, 2024 the Acting Under Secretary of State for Political Affairs determined that the Government of the Russian Federation has used chemical or biological weapons in violation of international law or lethal chemical or biological weapons against its own nationals.

The notice continued with sanctions and specific waivers.

Contrary to the fact sheet, the determination does not specify the nature of the violation, cite any specific incidents, or identify agents. Moreover, nothing in §5604 requires the President to publicise the sources for the determination. It just states that the President shall consider all available types of evidence; information provided by alleged victims, witnesses, and independent observers; the extent of the availability of the weapons in question to the purported user; relevant official and unofficial statements bearing on possible CW use; and whether the government in question is willing to consider an investigation by a fact-finding team under the UN (or the OPCW, as the CWC entered into force after the promulgation of the law). The President shall also promptly report the determination to Congress. According to §5605 of the CBW Act, the report shall specify the imposed sanctions if the determination asserts CBW use.

The list of available types of evidence to be considered hints at possible information resources. Thus, Ukraine’s oral statements and written communications to the OPCW accuse Russia of resorting to RCAs as a method of warfare. In addition, many reports in chat forums, on social platforms and in the press claim such use. The US likely collected intelligence inside Ukraine or via assorted national technical means such as communications intercepts. It may also obtain information via diplomatic exchanges and interactions at the OPCW. So, it can use many information sources to assess possible Russian CWC violations. Given the experiences in Syria and Russia’s frivolous approach to clarification requests under CWC Article IX, Washington is also convinced that Moscow will never allow an independent investigation into its violations of the 1925 Geneva Protocol or the CWC.

Back to the US statement on Russian chloropicrin use

The US determination surprised many people because of the sparsity of chloropicrin allegations in the public domain. In all, only three known messages in Ukrainian chat channels and social media have explicitly named the agent, and a couple more refer uncertainly to a chlorine smell. No official Ukrainian document or statement has thus far touched on chloropicrin or its delivery means (except for the one non-specific reference to improvised explosive devices).

How relevant are the chloropicrin allegations to the determination? As noted above, the fact sheet’s introduction suggests a one-to-one link between both. However, the next section on CW activities buttresses the determination by referring to Russia’s use of RCAs, noting that ‘the use of such chemicals is not an isolated incident, and is probably driven by Russian forces’ desire to dislodge Ukrainian forces from fortified positions and achieve tactical gains on the battlefield’. It also cites the use of the Novichok nerve agent in the assassination attempts against Sergei Skripal and his daughter in March 2018 and Alexei Navalny in August 2020.

In other words, why does the public rationale for the determination in the State Department fact sheet depend so much on the – by and large unsubstantiated – allegations of chloropicrin use, whereas Russia’s use of RCAs as a method of warfare is amply documented, even by Russian media outlets?

References to chloropicrin in US allegations

In its statements during the first quarter of 2024, the US seems to merely reiterate Ukrainian claims about Russian chloropicrin use rather than advancing its own assertions or adding details about specific incidents. For instance, in the Russia section of its Annual Report on Compliance with the CWC covering developments in 2023 and published on 4 April 2024, the State Department wrote:

At the 28th session of the OPCW [Conference of the States Parties] CSP, the Ukrainian representative asserted that Russian troops had begun adding the CWC Schedule 3 chemical Chloropicrin to grenades already containing RCAs.

However, according to the national statements available from the OPCW website made in the General Debate or under Agenda Subitem 9d, ‘Addressing the threat from chemical weapons use’ during the 28th CSP (27 November-1 December 2023), the Ukrainian representative did not publicly refer to chloropicrin. None of the Ukrainian documents in a lengthy compendium of Ukrainian and Russian communications with the OPCW Technical Secretariat name chloropicrin.

At the 105th session of the Executive Council meeting (5-8 March 2024), the Ukrainian representative intervened twice during the General Debate and under Agenda Item 7(e), ‘Addressing the threat from chemical weapons use’. The latter statement includes the addendum mentioning chloropicrin in connection with improvised explosive devices.

However, in its General Debate statement, the US asserted the Russian use of chloropicrin, which it characterised as a ‘choking agent’ rather than an RCA:

With regard to action to stop current use, Russian media sources have released videos describing and depicting the Russian military’s use of riot control agents as a method of warfare in Ukraine. Also, in mid-January, the General Staff of the Armed Forces of Ukraine noted that the frequency of Russia’s chemical use against Ukrainian forces is increasing, as is the variety of chemical munitions that Russian forces are using on the battlefield. Ukraine has reported the use of tear gas such as CS as well as use of chloropicrin – a choking agent included on Schedule 3.

As noted in the second blog instalment, only two sources linked to the Tavria Ukrainian military group on the southeastern front claimed Russian use of chloropicrin in January-February 2024.

Why refer to chloropicrin?

The obvious question is why chloropicrin had to occupy such a prominent place in the public rationale for the determination under the CBW Act. Why did the allegations by Ukrainian officials of Russian RCA use, multiple reports with images or film footage taken from drones in the press, online media and social platforms not suffice? The CWC spells out that using agents such as CN or CS as a method of warfare is prohibited. One can only speculate about the motives.

Still from Russian drone footage

The characterisation of chloropicrin as a choking agent may point to one reason. Depending on whether the emphasis lies on the purpose for using chloropicrin (riot control versus battlefield use) or the physiological impact on humans (lachrymation, skin irritation, vomiting or asphyxiation), the toxic agent fits multiple categories. When referring to ‘choking’, the US representative implied equivalence with chlorine or phosgene, the latter being by far the deadliest agent on the battlefields of the First World War. (I will return to the attribution of lethality in US arguments below.) They may have wanted to sound a warning about a possible escalation of toxic agents. After all, battlefield use of lachrymators preceded the introduction of more lethal agents in 1915 and the Iran-Iraq war.

Because all belligerents widely used chloropicrin as a casualty agent from 1916 on, it ended up in Schedule 3 of the CWC, indicating its risks to the convention and recognising its non-negligible global commercial significance. Due to its listing, no state party can possess chloropicrin for riot control purposes (CWC Art. II, 7). For any chloropicrin weapon still in its possession after the CWC entered into force, a state party should have declared it to the OPCW and destroyed it under its supervision.

The latter aspect is particularly significant. Russia tends to dismiss the general purpose criterion (GPC) at the heart of the CWC. Under the GPC, any toxic chemical (past, present, or yet to be discovered) is a CW by definition unless utilised for a purpose not prohibited by the convention (Article II, 1(a) and 9). Russian officials argue the primacy of the three schedules over the GPC. Therefore, they do not have to declare anything beyond the agents and precursors listed in the three schedules. Moscow never acknowledged possessing carfentanyl and remifentanyl before or after its use as an RCA or incapacitating agent during the Dubrovka theatre siege in Moscow in October 2002. Similarly, it only accepted to have certain Novichok agents and precursors included in Schedule 1 after the assassination operations against the Skripals and Navalny. Thus, forcefully charging Russian military units with chloropicrin use also accuses Moscow of violating the prohibition on CW development, production and stockpiling in keeping with its interpretation of the centrality of the schedules in the convention.

Still, this reasoning fails to explain why Washington would push ahead with such a charge if the evidence appears flimsy (at least in public). And the US has not really developed the allegation any further in the weeks after publishing the fact sheet. This leads to why the steeply mounting number of allegations of RCA use in December 2023 did not satisfy the conditions for a Presidential Determination under the CBW Act? Ukraine formally raised the matter under Subitem 9d at the 28th session of the CSP. We can envisage two scenarios.

The first scenario assumes that the US initiated the process for a formal determination on Russia’s RCA use at the end of 2023. After Ukrainian military sources alleged chloropicrin attacks in late January and early February 2024, officials added the new charge to the draft determination (perhaps giving it greater prominence for the reasons outlined above). This supposition would also explain the phrasing of the chloropicrin allegation in the US statement to the OPCW Executive Council early in March. It could also clarify why the State Department’s Annual Report on Compliance with the CWC, released on 4 April, included the chloropicrin allegation, citing the Ukrainian statements at the 28th session of the CSP. If one were to take out the mention of the agent, then the phrase ‘reports of use of other chemical agents by Russia in Ukraine’, together with the reference to the Ukrainian Permanent Representative’s assertions, would be correct. Similar reasoning could explain the prominence given to chloropicrin relative to other agents in the fact sheet.

A second imaginable scenario considers a different motive but with a similar outcome. The US has had a troubled relationship with RCAs for more than a century. After the First World War, the Chemical Warfare Service (CWS) emphasised the non-lethal characteristics of RCAs. It pushed their adoption by police forces as a way of institutional survival when public opinion and many countries were pressing for the abolition of chemical warfare. With this campaign, the CWS also blocked Senate ratification of the Geneva Protocol. While the US voluntarily abided by the prohibition on CBW use, it adopted a rather unique interpretation that the agreement applied to lethal agents only. After the US government admitted in March 1965 to widespread lachrymator use to clear the Viet Cong from tunnels and with the expansion of herbicide spraying over the Vietnamese forests that same year, international uproar about the violations of the Geneva Protocol prompted the UN General Assembly to adopt annual resolutions that clearly rejected the US reading of the ban. Those actions eventually led to the commissioning of studies into the nature and effects of chemical (and biological) warfare by the UN Secretary-General and the World Health Organisation and the start of the negotiations on the treaties banning CBW.

The US Senate ratified the Geneva Protocol in 1975, but not without President Gerald Ford issuing Executive Order (EO) 11850 – Renunciation of certain uses in war of chemical herbicides and riot control agents outlining the circumstances under which the US military could still use herbicides and RCAs in armed conflicts. Just over two decades later, EO 11850 became a flashpoint in the ratification of the CWC, and the Republican majority in the Senate imposed its preservation as one of the conditions for its consent two days before the CW ban was due to enter into force on 29 April 1997. While no US administration has invoked EO11850, the debate on its applicability, especially in counter-terrorism or urban combat contexts, has not stopped. The US Joint Staff issued the CWC Implementation and Compliance Policy Guidance on 12 April 2023. Enclosure C identifies the situations in which US military units may use RCAs.

In the second scenario, had the Presidential Determination under the CBW Act focussed exclusively on the allegations of Russian use of the CS and CN grenades, then the US would have risked exposing itself to charges of hypocrisy and massive Moscow-led disinformation and propaganda campaigns. When Ukrainian claims about chloropicrin started surfacing, the Schedule-3 toxicant offered a convenient deflector even if evidence continued to be scant.

For the fourth and final part

The above reflections on why the US State Department may have accentuated chloropicrin in its fact sheet of 1 May announcing the Presidential Determination on Russia’s CW use exposes the vast vagueness surrounding the regulation of any form of RCA use in the CWC.

An investigation of alleged use may clarify the allegations’ nature, scope and consequences. However, initiating such a process regarding RCAs may reveal some unforeseen issues.

The fourth part will investigate them.


Part 1: Chemical warfare allegations in the Ukrainian war

Part 2: Allegations of chloropicrin use

Part 4: The chloropicrin allegations and their implications for the CWC

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