The Chemical Weapons Convention: Preventative Measures Against Horror (Part 1 of 3)

This is the first blog post in a series of three blog posts discussing how the Chemical Weapons Convention prevents the use of chemical weapons through proactive measures by prohibiting both the use of and the preparation to use chemical weapons.  This first blog post describes key features of the Chemical Weapons Convention.  The second blog post compares the Chemical Weapons Convention to other sources of international law that address chemical weapons.  The third and final blog post examines recent events in Syrian Arab Republic, as a case study, to illustrate the concepts discussed in the first and second blog posts.


Part I: The Structure of the Chemical Weapons Convention

The Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on their Destruction—more commonly known as the Chemical Weapons Convention (the “CWC”)[1]—provides the strongest protection against chemical weapons in international law.  The CWC attempts “to exclude completely the possibility of the use of chemical weapons”[2] by destroying existing chemical weapons stockpiles and preventing production of new chemical weapons.  The CWC’s near-universal implementation and proactive enforcement structure provides the strongest protection in international law against the horrors of chemical weapons.  First, this post provides background on the CWC.  Second, it describes the international organization created by the CWC.  Third, it explains the CWC’s key provisions.  Finally, this post discusses the CWC’s enforcement and verification regime.


A. Background on the CWC

Early efforts at chemical weapons control provided deficient protections, and the CWC developed in response to that deficiency.[3]  The U.N. Conference on Disarmament adopted the final draft of the CWC on September 3, 1992, after twelve years of negotiation.  The CWC opened for signature on January 13, 1993, in Paris.  The CWC entered into force “180 days after the date of the deposit of the 65th instrument of ratification.”[4]  The sixty-fifth country—Hungary—ratified the convention in late 1996; after twenty-two countries ratified the CWC within 180 days of Hungary, the CWC entered into force on April 29, 1997 with eighty-seven State Parties.[5]  The Organization for the Prohibition of Chemical Weapons (the “OPCW”)—the international organization that administers the CWC—started functioning the same day the CWC entered into force.

opcw office

The OPCW office located in The Netherlands (AP)

The CWC faced early academic criticism.  For example, one early article concluded that the CWC “falls short because a significant number of nations with chemical warfare ability have not joined the treaty, these countries have little incentive to join in the near future, and the OPCW has limited powers to react to chemical attacks.”[6]  Nonetheless, the CWC and OPCW developed into formidable institutions.  Today, 190 countries have acceded to or ratified the CWC, leaving just six countries in the world that never acceded to or ratified the CWC.[7]  Additionally, after years of steady progress on the disarmament goals, the OPCW won the Nobel Peace Prize in 2013.

The six countries refusing to ratify or accede to the CWC are Israel, Myanmar-Burma, Angola, Egypt, North Korea, and South Sudan.  Each country’s refusal is troubling, but not necessarily surprising.  In terms of strategic international relations, ratifying the CWC and agreeing to its enforcement regime may not be rational for a state actor because a country that might have chemical weapons may be able to deter attack by enemies, based in part on that uncertainty.[8]  In the words of Sun Tzu: “All warfare is based on deception.”[9]  North Korea’s Kim-family dictators appear to act erratically, but calculatedly, to deter intervention in North Korea.  South Sudan is a war-torn country that is less than three years old.  Israel probably refuses to ratify the CWC to enhance its bargaining position in a region of enemies, particularly since continued non-recognition of the Palestinian state prevents a parallel ratification of the CWC by Palestine.  Some countries on this list probably do not possess chemical weapons, but others almost certainly do.  For example, in Burma-Myanmar, the current regime recently jailed reporters for “disclosing state secrets” by publicizing the government’s current, operating, chemical weapons factories.  Overall, the most striking thing about the list is that the list only contains six countries.  While the OPCW continues to work towards universality of membership, the CWC already applies in full force to 98% of the world.


B. The OPCW: The International Organization Created by the CWC

The OPCW oversees State Parties and redresses violations to supervise CWC compliance.  The OPCW conducted “more than 5,000 inspections in 86 countries” over its seventeen years of existence.  The OPCW monitored ninety-six declared chemical weapons facilities, overseeing the destruction of forty-three and conversion of twenty-two to peaceful purposes.  Some cite this behind the scenes work as the reason the OPCW won the Nobel Peace Prize in 2013—though the OPCW’s work in the Syrian Arab Republic that year certainly helped.

Article VIII created the OPCW, established the OPCW’s headquarters in the Hague, and divided the OPCW’s responsibilities among three organs.[10]  The first organ, the Conference of the States Parties (the “Conference”), consists of all OPCW members.[11]  The Conference oversees CWC compliance, oversees other parts of the OPCW, and redresses violations of the CWC.[12]  The second organ, the Executive Council consists of forty-one rotating members, elected for two-year terms and selected to ensure representation of each geographic region.[13]  One of the Executive Council’s responsibilities is to provide recommendations to the Conference about what measures to take in the event of non-compliance with the CWC by a State Party.[14]  The final organ, the Technical Secretariat, provides administrative and technical support to other parts of the OPCW, and carries out the verification measures described in the CWC, including on-the-ground investigations.[15]


C. Key Provisions of the CWC

Three subparagraphs of the CWC define of chemical weapons.  The first subparagraph covers toxic chemicals and their precursors; toxic chemical means “[a]ny chemical which through its chemical action on life processes can cause death, temporary incapacitation or permanent harm to humans or animals.”[16]  The Chemicals Annex lists the prohibited chemicals and their precursors.  The second subparagraph covers “[m]unitions and devices, specifically designed to cause death or other harm through the toxic properties of those toxic chemicals” identified in the first part of the definition.[17]  The third part covers equipment specifically designed for use directly in connection with the employment of munitions and devices” identified in part two.[18]  The CWC prohibitions rely on this three-part definition of chemical weapons.  The CWC and the OPCW classify chemical weapons by their “mode of action” on victims, meaning how the chemical enters and affects the body.  Categories of chemical weapons include choking agents, blister agents, blood agents, and nerve agents.

Chemical weapons are distinguishable from biological weapons.  Chemical weapons are generally man-made chemicals, while biological weapons are weaponized versions of naturally occurring bacteria and viruses.  The 1972 Biological Weapons Convention (“BWC”) prohibits the development, production, and stockpiling of biological weapons.  The broad chemical weapons definition in the CWC could be interpreted to include some biological weapons, where the “possible use is similar” for biological agents and chemical agents.  Thus, the CWC states that nothing in the CWC “shall be interpreted as in any way limiting or detracting from the obligations assumed by any State under” the BWC.[19]  The protections of the CWC and BWC complement each other, but the two treaties address different types of weapons.

State Parties only give up the rights the CWC expressly prohibits.[20]  Thus, the CWC contains excruciating detail to protect against chemical weapons.  This produced what one author described as “the most complex disarmament and nonproliferation treaty in history.”[21]  As a starting point, Article I identifies the general obligations of State Parties under the CWC:

1. Each State Party to this Convention undertakes never under any circumstances:

(a) To develop, produce, otherwise acquire, stockpile or retain chemical weapons, or transfer, directly or indirectly, chemical weapons to anyone;

(b) To use chemical weapons;

(c) To engage in any military preparations to use chemical weapons;

(d) To assist, encourage or induce, in any way, anyone to engage in any activity prohibited to a State Party under this Convention.

2. Each State Party undertakes to destroy chemical weapons it owns or possesses, or that are located in any place under its jurisdiction or control, in accordance with the provisions of this Convention.

3. Each State Party undertakes to destroy all chemical weapons it abandoned on the territory of another State Party, in accordance with the provisions of this Convention.

4. Each State Party undertakes to destroy any chemical weapons production facilities it owns or possesses, or that are located in any place under its jurisdiction or control, in accordance with the provisions of this Convention.

5. Each State Party undertakes not to use riot control agents as a method of warfare.[22]

Article I prohibits the most troubling aspects of chemical weapons.  Paragraph 1 prohibits State Parties from using, producing, or stockpiling chemical weapons; it prohibits all preparations to use chemical weapons and prohibits facilitating any third party—including non-state terrorist actors—to prepare to use chemical weapons.  Paragraphs 2-4 ensure the destruction of existing chemical weapons and existing production facilities.  Paragraph 5 expressly prohibits the use of riot control agents in warfare, which clarifies that the permitted for use for domestic law enforcement purposes—under Article VI—does not lead to use of chemical agents in warfare.  Moreover, Article XXII expressly prohibits any State Party from making any reservation to the CWC’s terms.[23]  Thus, all State Parties agree to the exact same limitations, including agreement never to retaliate with chemical weapons.

After a country ratifies or accedes to the CWC, the country must secure compliance by public and private actors within the country.  For example, the provisions addressing chemical weapons production facilities “shall apply to any and all chemical weapons production facilities owned or possessed by a State Party, or that are located in any place under its jurisdiction or control.”[24]  This enables the OPCW to oversee the destruction or conversion to peaceful use of both privately and publicly held chemical weapons factories, which includes both chemical factories and munitions factories under the CWC definition of chemical weapons.  State Parties must enact penal legislation to criminalize actions prohibited by the CWC, which ensures the accountability of private actors.[25]  The OPCW website provides suggestions for how State Parties should implement the CWC through domestic legislation and regulations.

The broad definition of chemical weapons in Article II specifically excludes chemicals that are used for a “purpose not prohibited” by the CWC, as long as the type and quantity is consistent with such purpose.[26]  The list of purposes not prohibited by CWC recognizes that some chemicals used in chemical weapons also have legitimate, economically beneficial purposes.[27]  When a State Party wishes to use an otherwise prohibited chemical for any of these non-prohibited purposes, the State Party must submit to verification measures overseen by the OPCW, as described in the next section.

libya chemical weapon destruction facility

Members of the OPCW visit a chemical weapons destruction facility in Libya in Feb. 2014 (OPCW/Flickr)

The most controversial use allowed by the CWC is the exception for the purpose of “Law enforcement including domestic riot control purposes.”[28]  The ICRC criticizes the use of any toxic chemicals for law enforcement purposes, mainly out of slippery-slope concerns about undoing the progress towards chemical weapons disarmament in international law.[29]  The ICRC vice-president expressed concern about any potential use of toxic chemicals by law enforcement in this video.  Others express concerns about the ambiguous scope of the phrase “law enforcement.”[30]  The language of this exception could have been more clearly limited to cover a narrow list of chemical agents—such as pepper spray—to guarantee uniform compliance.  State Parties must declare the possession of chemicals useable as riot control agents to the OPCW, as with possession of any chemical listed in the Chemicals Annex, but they are not required to report when or how riot control agents are used.[31]  However, if the OPCW becomes concerned about how a State Party interprets this provision, Article XIV addresses conflicts of interpretation between a State Party and the OPCW, and Article XV describes procedures for amending the CWC.[32]


D. Verifications, Inspections, and CWC Enforcement

The CWC’s enforcement and verification system monitors disarmament, monitors chemical industries, and undertakes through short-notice inspections.  As described by the ICRC, one “major innovation of the CWC is its intrusive verification regime.”  That regime defines the roles of the State Party and the OPCW before, during, and after the initial implementation of the CWC.  The process starts with State Parties submitting initial declarations to the OPCW, including a detailed inventory and a plan for the destruction of all existing chemical weapons stockpiles and chemical weapons production facilities.[33]  Creating and implementing the destruction plans can be challenging, especially due to the environmental problems inherent in destroying chemical weapons.[34]  Nonetheless, the Verification Annex provides instructions: it outlines the order of destruction for chemical weapons and describes the on-site inspections used throughout the destruction process.[35]

After the initial implementation of the CWC, State Parties must submit to OPCW monitoring whenever a they wished to use otherwise prohibited chemicals for a non-prohibited purpose.  The Annex on Chemicals divides chemicals into three schedules, and verification measures under the Verification Annex vary based on the chemical’s location in the three schedules.[36]  This structure allows the OPCW to certify a State Party’s compliance by monitoring production of chemicals that could become or be used as chemical weapons, even when the intended use of the chemical is not prohibited by the CWC.[37]

State Parties may call on the OPCW to investigate any concerns about another State Party’s compliance with the CWC through a “challenge inspection.”[38]  The challenging State Party submits a request to the Executive Council of the OPCW, and unless concerns about the validity of the request stop the process, preparations for an inspection will begin.[39]  The CWC requires that State Party submit to challenge inspection by the Technical Secretariat, under an accelerated timeline: the inspected party may receive as little as twelve-hours of notice of the inspection team’s arrival.[40]  The challenge inspection contains different procedures for claims the State Party actually used chemical weapons and for claims of other violations.[41]  However, the timeline for responding to a challenge inspection remains the same for all alleged violations; this indicates that the CWC treats production and stockpiling of chemical weapons very seriously.

emergency response training

The OPCW conducts a training course on emergency response to chemical incidents for Asian State parties (OPCW/Flickr)

First, the Executive Council reviews the inspection team’s final report; then, if the report reveals non-compliance with the CWC, it makes recommendations for action to the Conference.[42]  Article XII’s four relatively short and relatively broad paragraphs describe the measures for redressing noncompliance.[43]  By not specifying how to redress specific violations, the CWC enables the Executive Council and the Conference to be creative and to respond with anything from sanctions to aggression.  The OPCW must notify the U.N. General Assembly and the U.N. Security Council of “cases of particular gravity.”[44]  To some extent, this envisions the two international organizations working together.  The OPCW and the U.N. do work together sometimes.  For example, where allegations of chemical weapons use arise in connection with a non-State-Party and the U.N. asks for help, the CWC commands the OPCW “to put its resources at the disposal of the Secretary-General of the United Nations.”[45]  This ensures that the OPCW’s expertise will be available when it may be most vital.

However, nothing in Article XII prevents the Conference from taking collective action more quickly than the U.N. Security Council.  Instead, “where serious damage to the object and purpose of [the CWC] may result from activities prohibited under [the CWC], in particular by Article I, the Conference may recommend collective measures to States Parties in conformity with international law.”[46]  Perhaps the possibility that the U.N. would refuse to act in the face of a situation serious enough to inspire independent action by the Conference is sufficiently unlikely that this will never be an issue.  The U.N. Charter provides the Security Council with “primary responsibility for the maintenance of international peace and security.”  Nonetheless, the option for independent collective action by the Conference could be a helpful alternative to the Security Council veto, in a hypothetical situation involving the use of chemical weapons alongside regional conflicts of interest.


E. Conclusion

The best features of the CWC are the abilities of the OPCW: to interfere in a country’s chemical industry; to oversee both chemical weapons and precursor chemicals; to investigate actions of private and public actors; to monitor the destruction of chemical weapons; to guarantee the destruction, rather than the transfer, of chemical weapons.  Overall, the OPCW prevents the use of chemical weapons by removing them from international commerce and from State Parties.  Sure, the CWC theoretically could be better, but everything could be better: perfection in international law, as in life, is a goal rather than a reality.  But the strengths of the CWC cannot be overemphasized.  As will be shown in the next blog post in this series, the CWC provides exponentially more powerful protection against chemical weapons than other sources of international law.  To show how this system looks in practice, the third and final blog post discusses events before and after the Syrian Arab Republic ratified the CWC in 2013.


Katharine York is a third year law student at the University of Denver Sturm College of Law and a staff editor for the Denver Journal of International Law and Policy


[1] Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons, opened for signature Jan. 13, 1993, S. Treaty Doc. No. 103-21, 1974 U.N.T.S. 45 [hereinafter CWC].

[2] Id. at pmbl.

[3] For more information about other sources of international law addressing chemical weapons, see the second post in this three part series.

[4] CWC supra note 1, at art. XXI.

[5] The CWC refers to countries that have ratified or acceded to the CWC as “State Parties.”

[6] Kevin J. Fitzgerald, The Chemical Weapons Convention: Inadequate Protection from Chemical Warfare, 20 Suffolk Transnat’l L. Rev. 425, 447 (1997).

[7] Countries that were not signatories of the CWC before the CWC entered into force cannot ratify the CWC; however, any country may accede to the CWC.  CWC, supra note 1, at arts. XIX-XX.

[8] See Thomas Schelling, Strategy of Conflict 3-80, 119-61 (1980 ed.) (explaining that the ability to communicate strength—either overtly or tacitly—is essential for deterrence).

[9] Sun Tzu, The Art of War 9 (Dallas Galvin ed., Lionel Giles trans., 2003 Barnes & Noble Classics) (1910).

[10] CWC, supra note 1, art. VIII, para. 1, 3, and 4.

[11] Id. at art. VIII, para. 9.

[12] Id. at arts. VIII, para. 20, XII, para. 1.

[13] Id. at art. VIII, para. 23.

[14] Id. at art. VIII, paras. 35-36.

[15] Id. at art. VIII, para. 38.

[16] Id. at art. II, para. 1-3.

[17] Id. at art. II, para. 1.

[18] Id.

[19] Id. at art. XIII.

[20] Id. at art. VI, para. 1 (“Each State Party has the right, subject to the provisions of this Convention, to develop, produce, otherwise acquire, retain, transfer and use toxic chemicals and their precursors for purposes not prohibited under this Convention.”) (emphasis added).

[21] Urs A. Cipolat, The New Chemical Weapons Convention and Export Controls: Towards Greater Multilateralism?, 21 Mich. J. Int’l L. 393, 394 (2000).

[22] CWC, supra note 1, at art. I, para 1.

[23] Id. at art. XXII.

[24] Id. at art. V, para. 1.

[25] Id. at art. VII, para. 1.

[26] Id. at art. II, paras. 1-4.

[27] Id. at art. II, para. 9 (“‘Purposes Not Prohibited Under this Convention’ means: (a) Industrial, agricultural, research, medical, pharmaceutical or other peaceful purposes; (b) Protective purposes, namely those purposes directly related to protection against toxic chemicals and to protection against chemical weapons; (c) Military purposes not connected with the use of chemical weapons and not dependent on the use of the toxic properties of chemicals as a method of warfare; (d) Law enforcement including domestic riot control purposes.”).

[28] Id.

[29] For more information about the ICRC’s contributions to the discussion of customary international law on chemical weapons, see the second post (upcoming) in this three part series.

[30] Benjamin Kastan, Note, The Chemical Weapons Convention and Riot Control Agents: Advantages of a “Methods” Approach to Arms Control, 22 Duke J. Comp. & Int’l L. 267, 271-72 (2012).

[31] James D. Fry, Gas Smells Awful: U.N. Forces, Riot-Control Agents, and the Chemical Weapons Convention, 31 Mich. J. Int’l L. 475, 485 (2010).

[32] CWC, supra note 1, at arts. XIV, para. 2, art. XV.

[33] Id. at art. III and Verification Annex.

[34] See generally David A. Koplow, How Do We Get Rid Of These Things?: Dismantling Excess Weapons While Protecting The Environment, 89 Nw. U.L. Rev. 445 (describing the environmental issues related to destroying chemical weapons and chemical weapons production facilities).

[35] CWC, supra note 1, Verification Annex, Part. IV(A), para. 15 and 37.

[36] Id. at art. VI, Annex on Chemicals.

[37] Id. at Verification Annex.

[38] Id. at art. IX, paras. 8-25.

[39] Id. at art. IX, para. 17.

[40] Id. at art. IX, para. 15.

[41] Id. at art. IX, para. 19.

[42] Id. at arts. IX, paras. 22-25, art. XII, para. 1.

[43] Id. at art. XII.

[44] Id. at art. XII, para 4.

[45] Id. at Verification Annex, Part XI, para. 27.

[46] Id. at art. XII, para 3.



One Response to “The Chemical Weapons Convention: Preventative Measures Against Horror (Part 1 of 3)”


  1. […] to ensure that state parties relinquish weapons that the CWC expressly prohibits. Katharine York elaborated on the purpose of the CWC in article in the Denver Journal of International Law and Policy last […]

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