The Legal Paradox of International Chemical Riot Control Regulations

By Katja Knoechelmann*

Publication date: 3 October 2012

Type: Article

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This paper deals with the legal paradox that arises in international riot control regulations. While it is permitted to use chemical riot control agents in times of peace, it is mostly prohibited during times of armed conflict. This, the author believes, runs contrary to the logic that armed conflict situations classify as emergency situations in which certain rights and comforts of the population may be suspended temporarily. Several case studies are given to explain different countries acting in this legal paradox. Three explanations are proposed for the existence of such a paradox:

(1) the slippery slope argument that the introduction of chemical riot control agents on the battlefield could result in easy use of other chemicals on the battlefield, namely chemical weapons;

(2) the sanctity of national sovereignty and the lack of regulation in the human rights law paradigm; and

(3) that the main and initial purpose of chemical riot control lies in controlling the civilian population during times of riot, therefore mainly illuminating its purpose during armed conflict which focuses on controlling actions of enemy combatants and granting protection to the civilian population, rather than making it the object of focus.


The suppression of riots has been one of the key functions of law enforcement for centuries. While there are times when the military takes on this role, riots mostly occur during peaceful times and therefore are handled by police forces. With the introduction of chemicals into riot suppression in the early twentieth century, riot control has taken on a new shape. This, until today, is met by some with fierce opposition. While the chemicals used for riot control are becoming increasingly less lethal and safer, a legal paradox has arisen in its regulation. More specifically, since the almost unanimous acceptance and ratification of the Chemical Weapons Convention in 1993, states have agreed to a prohibition of use of chemical riot control agents as a method of warfare, yet, refuse to legislate and enforce such a prohibition for times of peace. In other words, riot control agents are lethal enough to fall under the Chemical Weapons Convention, but in domestic affairs during times of peace, when human rights law is the applicable legal regime, these same riot control agents are accepted as a riot suppressant against civilians. Israel´s Manual on the Rules of Warfare summarized the failure of logic behind the legislation addressing riot control agents very precisely when it states: “Apparently, even the tear gas used by the police to disperse demonstrations is a chemical weapon and thus prohibited under the Protocol, despite its relatively minor effect. An absurd situation results in which demonstrators are “endangered” by tear gas whereas fighters going out of battle are protected from it”.1

In a world where characteristics of adversaries are constantly changing and the difference between peace and war becomes increasingly blurred through low intensity asymmetrical conflict and terrorism, countries often enter a grey zone in which not even the highest international bodies, such as the UN Security Council, are sure of which legal framework applies. In case of riot control agents the misuse becomes a temptation which is often followed up upon due to its many advantages on the battlefield.

Chemical riot control agents such as tear gas or pepper spray have many advantages. Although they sometimes result in fatalities, they are an effective method to disperse and gain control over crowds by temporarily incapacitating demonstrators and other civilians. Under international humanitarian law, the body of law applicable during armed conflict, two nations at war are legally allowed to kill each other´s combatants without legal repercussions. Combatants pose legal military targets. While for many centuries no humanitarian thought was given to military casualties on the enemy´s side, this is changing. Capture when possible as opposed to kill is becoming the norm, at least among Western nations with democratic and liberal value systems. Does then the prohibition on riot control agents as a method of warfare not seem hypocritical? Riot control agents pose a non-lethal alternative to a shoot-to-kill strategy.

The literature has dealt plenty with the use and prohibition of chemical weapons through the ages, yet it has rarely focused on the use of riot control agents in its legal setting. In recent decades a new category has emerged within the field of armed conflict literature termed “non-lethal” weaponry. While chemical riot control agents fall within this category, they are only one “non-lethal” alternative among many. Nick Lewer and Neil Davidson discuss the various forms of non-lethal means based on chemicals including malordorments, anti-traction materials, obscurants, foams, anti-materiel chemicals, herbicides, and, of course, chemical riot control agents.2 Lewer and Davidson, among many,3 propose the increased use of non-lethal weapons in warfare.4 With the increasing controversy surrounding the use of chemical riot control agents against civilian populations, especially as expressed through vivid pictures of the recent Occupy protests worldwide as well as accounts of the Arab Spring, more has been written on the use of riot control agents and even on the prohibition of use during certain situations. This debate heightened especially in situations when circumstances during the Arab Spring became increasingly violent and the opposition against the various regimes became so organized that it was unclear whether an armed conflict had erupted or not. David P. Fidler, a professor of law at Indiana University, delved deeper into the use of non-lethal technologies, using the Moscow theatre tragedy of 2002, as an example to illustrate his claim.5 Although focusing on the Moscow theatre tragedy, which is an example of use of riot control agents, Fidler inherently focuses on the general debate on non-lethal technologies under international law. He discusses the ethical debate among experts and analyzes the use of fentanyl (agent used by security forces in the Moscow example) under international humanitarian law. Yet, Fidler only touches on the difference in between the application during human rights law governed situations and those situations governed by international humanitarian law. He does not ask why this difference persists contrary to logical analysis. This paper will focus on a legal analysis of this phenomenon taking into consideration several case studies. It will begin by defining riot control agents and explaining the development of these agents over time. Then, the paper will continue with a detailed legal analysis of the prohibition during armed conflict, followed by an analysis of human rights law for times of peace. The difficulties and challenges of countries facing this paradox will be illustrated through four case studies of Germany, the Russian Federation, Israel and the United States of America. I will conclude by explaining why introducing chemical riot control agents on the battlefield should be considered a life-saving measure, and not a step towards escalation.

The research used for this paper is mainly based on written law from various conventions and other sources of law that govern the given situations. Although I try to illustrate the workings of the law by giving examples from the field to complement the law, the paper is legal in nature. Some may claim that this is a potential limitation to the paper as law may be interpreted as theoretical in nature, however I believe that the paper finds a healthy balance between textbook and reality.

By writing this paper I hope to shed more light on the existing legal paradox and hope that it will help experts and policymakers reconsider their previous policies with regards to the prohibition of chemical riot control agents during times of armed conflict, as it is my personal belief that they can and should pose a non-lethal alternative in a deadly environment.

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* Ms. Katja Knoechelmann has attained a BA in Government and Diplomacy from the Interdisciplinary Centre Herzliya in Israel and an MA in Counter-terrorism and Homeland Security at the same institution. The author is currently enrolled in an MSc program in International Development and Humanitarian Emergencies at the London School of Economics and Political Science. Ms. Knoechelman is a winner of the 2011 world competition on International Humanitarian Law, the Concours Jean Pictet.



  1. Israel (2006). Rules of Warfare on the Battlefield, Military Advocate-General´s Corps Command, IDF School of Military Law, Second Edition, p. 19.

  2. Davidson, N., & Lewer, N. (2005). Non-Lethal technologies – an overview. Disarmement Forum. Science, Technology and the CBW Regimes, 1, p. 36-51.

  3. Siniscalchi, J., USAF Colonel. (March 1998). Non-lethal technologies: Implications for Military Strategy. Center for Strategy and Technology, Air University, Maxwell Air Force Base, Occassional Paper No. 3. Retrieved on August 1, 2012 from:

  4. Garwin, R. L., & Montague Winfield, W. (1999) Nonlethal Technologies: Progress and Prospects. Council of Foreign Relations.

  5. Fidler, D. P. (September 2005). The meaning of Moscow: „Non lethal” weapons and international law in the 21st century. International Review of the Red Cross, Volume 87, No. 859.