Riot-control agents banned

The ban on the use of chemical weapons, as codified in the 1925 Geneva Protocol, was considered to constitute international law, applicable to all states. Yugoslavia had ratified the protocol and at no time indicated any desire to repudiate its treaty obligations. In earlier years certain countries, including the United States which used massive quantities of tear gas in the Vietnam War, maintained the protocol did not ban the use of riot control agents. However, incapacitating agents, like BZ, were not included in this apparent exception. 

Rosenberg, B.H. (2003). Riot control agents and the Chemical Weapons Convention. The Open Forum on Challenges to the Chemical Weapons Ban, May 1. 

Toxic ammunition contains chemical agents which, through their adverse physiological effects, are in use by military or law enforcement organizations to kill, injure, or incapacitate humans. Less powerful agents are used by the public for self-defense. While the use of lethal chemical agents like mustard gas and nerve agents to kill or maim has been banned by the Chemical Weapons Convention (COTC), the use of toxic chemicals as suppressive methods to control or subdue crowds and riots is widespread. 

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