Global Security: Non-Proliferation - Foreign Affairs Committee Contents

 Further submission from Mr Nicholas A Sims, Reader in International Relations, London School of Eonomics and Political Science


(REF Questions 82 and 83)

Nicholas Sims


  1.  The only explicit reference to herbicides in the CWC is preambular: "Recognizing the prohibition, embodied in the pertinent agreements and relevant principles of international law, of the use of herbicides as a method of warfare". This is preambular paragraph 7. By its very nature a preambular reference does not constitute a treaty obligation but reflects the intentions of the negotiators and the context of existing law and institutions which they regarded as particularly relevant to the new treaty.

  2.  During the negotiation of the CWC the Committee on Disarmament (constituted in 1979) and the Conference on Disarmament (as it was renamed in February 1984) worked through an Ad Hoc Working Group and later an Ad Hoc Committee on Chemical Weapons. The Ad Hoc Committee in turn set up working groups at different times to deal with particular aspects of the drafting of the CWC. This substructure helped the Committee elaborate a draft known as the Rolling Text between 1984 and 1992, which was pruned of square brackets and footnotes in 1992 first by Australia and then by Germany (as the 1992 Chairman of the Ad Hoc Committee) and became the basis of the eventual Convention. Negotiations were concluded at Geneva on 26 August 1992; the Convention was adopted by the Conference on Disarmament on 3 September 1992 and opened for signature at Paris on 13-15 January 1993, entering into force on 29 April 1997.

  3.  The use of defoliants and herbicides during the Vietnam War was well known to the Conference on Disarmament and there was a possibility that they might be covered by the eventual CWC. The sensitivity for the United States of the issue of defoliants and herbicides resulted in special handling of this issue. It was sidelined for some time into the "Wisnomoerti conversations", chaired by the Deputy Permanent Representative of Indonesia to the Conference on Disarmament (Mr Wisnomoerti), to avoid the risk of deadlock to the drafting work being undertaken in the Ad Hoc Committee and its main substructure of working groups. Being thus kicked into touch the issue would not delay progress in the negotiations until (if at all) near their end.

  4.  The outcome of the Wisnomoerti conversations was inconclusive: square-bracketed (ie disputed) draft language and a (Swedish) footnote to the Rolling Text which was carried forward in that form until 1992. This noted that the placement of any reference to herbicides in the CWC and in particular their coverage under Article II (Definitions) remained to be decided. In May 1992 an attempt to put herbicides into Article I and thereby make their use as a method of warfare an object of prohibition on a par with all the other CWC prohibitions[362] was unsuccessful, and after "intensive negotiations under the moderatorship of Australian Ambassador O'Sullivan, near consensus was reached to drop this prohibition under Article I and instead make reference to the recognition of such a prohibition in the Preamble".[363] The Chairman of the Ad Hoc Committee, Ambassador von Wagner, explained why he was recommending this compromise, on 26 June 1992: "in many years of negotiations positions had remained contentious on whether and how the possible war-time use of so-called 'herbicides'…should be dealt with in the Convention, as witnessed by footnotes and bracketed text which stayed untouched until recently" and he was therefore recommending "a new seventh paragraph in the Preamble, reiterating the already existing prohibition on the use of herbicides as a method of warfare."[364]

  5.  A legal commentary on the definitive text of the Convention was published in 1994 by Dr Walter Krutzsch and Dr Ralf Trapp, both closely associated with the 1992 concluding stage of negotiations at Geneva and then with the setting up of the OPCW at The Hague. They point out that Article II.2 defines toxic chemicals in terms of their effects on humans or animals only:

    "The definition excludes… toxicity against plants. Herbicides will not be regarded as chemical weapons if used with an intent to destroy plants. That would even apply if the (secondary) effect of such use were the killing or harming of people, for example by toxic side effects or by denial of food supplies. On the other hand, herbicides would be covered if they were used in order to directly kill or harm people through their toxicity. It could also be argued that military use of herbicides in an 'anti-plant' mode yet at a dosage that would make collateral toxic effects in humans inevitable would be prohibited under the Convention."[365]

    "This peculiar treatment of anti-plant chemical agents under the CWC has often been explained by the implications for legitimate civilian and military uses of herbicides. The latter could include, inter alia, such activities as clearing airfields or perimeters of military bases. Another argument has been that excessive use of herbicides is already covered under the ENMOD Convention. During the negotiations for the ENMOD-Convention the USA made an interpretive Statement on this subject: 'In our view the Convention would prohibit such use of herbicides as a means of destruction, damage, or injury if the effects were widespread, long-lasting or severe…' The 1992 Review Conference on the ENMOD Convention agreed in its Final Document on a similar statement."[366] That 1992 statement added that the ENMOD criteria would be met "if such a use of herbicides upsets the ecological balance of a region."[367]

  However, Krutzsch & Trapp also comment that

    "The argument that anti-plant chemical weapons should not be covered by the CWC as they are already covered under the ENMOD treaty has little legal validity. That treaty only relates to use in war, not to possession or development."[368]


  6.  Sir John Stanley went on to ask: "if it is merely in the preamble, is it a policy development that the British Government should press for when we come to the next review?"

  7.  It would indeed be desirable to revisit the issue of defoliants and herbicides, but within the wider category of toxic chemicals. The Third Review Conference in 2013 should be encouraged to revisit definitions to clear up loose ends or uncertainties, of which this is one; another, which neither of the first two Review Conferences was keen to take up, is the status of "non-lethal" chemical agents other than when used for domestic riot control purposes or for other (very limited) purposes of law enforcement as understood while the CWC was under negotiation. The Convention bans the use of riot control agents as a method of warfare, in Article I.5, but not the possession of such agents for non-prohibited purposes. "Purposes not prohibited under this Convention" are defined in Article II.9.d as including "Law enforcement including domestic riot control purposes". The definition of "Military purposes not connected with the use of chemical weapons and not dependent on the toxic properties of chemicals as a method of warfare" as another category of non-prohibited purposes (Article II.9.c) may also need attention in relation to some military uses of defoliants and herbicides. The issue of "non-lethals" is a complicated one both because the science and technology involved are controversial and because it touches on several different points in the text of the Convention.

  8.  The issue will only be tackled by the Third Review Conference if some States Parties to the CWC start pressing for this several years in advance, so that it is not just nominally on the agenda but is accompanied as an agenda item by proposals for extended understandings which would define toxic chemicals for CWC purposes so as to encompass defoliants and herbicides and other "non-lethal" chemical agents within the Convention. It would be good if the British Government would press for this.

  9.  As pointed out at the end of paragraph 5 above, the Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques (ENMOD) of 18 May 1977 (in force since 5 October 1978) only bans the use of such techniques— and then only if the use is for military or any other hostile purpose and has effects which are widespread, long-lasting or severe as the means of destruction, damage or injury to another State Party. The activities banned by the CWC, on the other hand, include not only use but also a whole set of logically prior activities: development, production, stockpiling, acquisition, retention, transfer and military preparations to use chemical weapons. Effectively they rule out a CW programme. How widely this should be defined depends inter alia upon the definition of toxic chemicals, and this definition—in the spirit of the "general purpose criterion" which the UK has consistently championed—needs to be rendered wider rather than narrower so as to prevent circumvention of the CWC.

362   Conference on Disarmament document CD/CW/WP.400, cited in Walter Krutzsch & Ralf Trapp, A Commentary on the Chemical Weapons Convention (Dordrecht: Martinus Nijhoff, 1994) p 31 footnote 25. Back

363   Conference on Disarmament documents CD/WP/WP.400/Rev.1 and /Rev.2. Krutzsch & Trapp, p 31 footnote 25. Back

364   Conference on Disarmament, Ad Hoc Committee on Chemical Weapons, Chairman's Explanatory Note CD/CW/WP.414. Krutzsch & Trapp, p 8 footnote 5. Back

365   Krutzsch & Trapp, p 30 and footnote 21. Back

366   Krutzsch & Trapp, p 30 and footnote 24. Back

367   Paragraph 11 of the Final Declaration of the 1992 ENMOD Review Conference. Krutzsch & Trapp, p 9 and footnote 6. Back

368   Krutzsch & Trapp, p 30. Back

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