http://www.icrc.org/...
The Geneva Conventions and their Additional Protocols are at the core of international humanitarian law, the body of international law that regulates the conduct of armed conflict and seeks to limit its effects. They specifically protect people who are not taking part in the hostilities (civilians, health workers and aid workers) and those who are no longer participating in the hostilities, such as wounded, sick and shipwrecked soldiers and prisoners of war
Chemical and biological weapons
08-04-2013 Overview
The international community banned the use of chemical and biological weapons after World War I and reinforced the ban in 1972 and 1993 by prohibiting the development, production, stockpiling and transfer of these weapons. Today’s advances in life sciences and biotechnology, as well as changes in the security environment, have increased concern that long-standing restraints on the use of chemical and biological weapons may be ignored or eroded.
The Protocol has been respected in nearly all of the hundreds of armed conflicts that have taken place since 1925. The handful of well-known and high-profile violations have provoked widespread international condemnation and in some cases criminal prosecutions.
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Common Article 3 relating to Non-International Armed Conflict
This article states that the certain minimum rules of war apply to armed conflicts that are not of an international character, but that are contained within the boundaries of a single country. The applicability of this article rests on the interpretation of the term armed conflict.[17] For example it would apply to conflicts between the Government and rebel forces, or between two rebel forces, or to other conflicts that have all the characteristics of war but that are carried out within the confines of a single country. A handful of individuals attacking a police station would not be considered an armed conflict subject to this article, but only subject to the laws of the country in question.[17]
The other Geneva Conventions are not applicable in this situation but only the provisions contained within Article 3,[17] and additionally within the language of Protocol II. The rationale for the limitation is to avoid conflict with the rights of Sovereign States that were not part of the treaties. When the provisions of this article apply, it states that:[18]
Persons taking no active part in hostilities, including military persons who have ceased to be active as a result of sickness, injury, or detention, should be treated humanely and that the following acts are prohibited:
violence to life and person, in particular murder of all kinds, mutilation, cruel treatment and torture;
taking of hostages;
outrages upon personal dignity, in particular humiliating and degrading treatment; and
the passing of sentences and the carrying out of executions without previous judgment pronounced by a regularly constituted court, affording all the judicial guarantees which are recognized as indispensable by civilized peoples.
The wounded and sick shall be collected and cared for.
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Hague Convention of 1899
Declaration concerning the Prohibition of the Use of Projectiles with the Sole Object to Spread Asphyxiating Poisonous Gases
This declaration states that, in any war between signatory powers, the parties will abstain from using projectiles "the sole object of which is the diffusion of asphyxiating or deleterious gases." Ratified by all major powers, except the United States.[14]