The statistical results of Chapter 4 provide the broad pattern of compliance with the laws of war. This chapter complements those results by looking at the details of compliance with a specific area of the laws of war, the treatment of prisoners of war (POWs). Treatment of POWs is a good candidate for detailed study because there is wide variation in compliance with the treaties, compliance depends on what happens at the state and the individual level, and the clarity of obligations increased from World War I to World War II. POWs then allow a test of the central ideas of compliance discussed in Chapter 3. Additionally, POWs is an issue in the laws of war which has received less attention than others such as the use of chemical weapons. The next chapter provides some brief analysis of the issues which have received more attention in the political science literature. I limit this chapter to the World Wars simply to allow a coherent presentation. Later wars, particularly the Korean War, the Vietnam War, and the Iraq-Iran War, presented interesting issues in the treatment of POWs, but adding them to this discussion would lengthen it substantially without adding new leverage on the hypotheses to be tested.

This chapter begins with a discussion of the relevant treaties and the obligations they impose on state parties. Then I discuss the strategic logic of POWs; how different states perceived their interests in how they treat POWs. The issue of POWs operates at both the state level – what are state policies toward enemy soldiers who attempt to surrender – and at the individual level – what soldiers do on the battlefield. Furthermore, the two levels are connected; state policy attempts to regulate how their own soldiers act and induce enemy soldiers to act, but the success of those policies depends on the logic of the battlefield.