In the context of any armed conflict, the topic of war crimes inevitably arises, especially in reports of civilian and military casualties and the taking of prisoners of war. The idea of a "war crime" seems to be pretty redundant: Most of us are familiar with the phrase "All is fair in love and war," and in an armed conflict, in which the killing of enemy troops is considered an acceptable means to an end, it may seem that the concept of a "crime" is out of place. But there are countless treaties that declare otherwise, signed by almost every nation in the world.

The Hague laws and Geneva Conventions are some of the most widely applied of these international agreements. These treaties address, among other issues, the participants of war, the victims of war, occupation by hostile forces and the status of cultural property. In the 2003 war in Iraq, Iraqi troops waved a white flag and then opened fire on the U.S. soldiers who approached to accept their surrender; this act is prohibited under the Hague laws. In World War II, the Nazis in Germany performed medical experiments on civilians; this act is prohibited in all of the Geneva Conventions.

More about Geneva Conventions: Books

http://www.unhchr.ch/html/menu3/b/91.htm : Geneva Convention relative to the Treatment of Prisoners of War Adopted on 12 August 1949 by the Diplomatic Conference for the Establishment of International Conventions for the Protection of Victims of War, held in Geneva from 21 April to 12 August, 1949