International humanitarian law

In addition to prescribing laws governing resort to force ( jus ad bellum ), international law also seeks to regulate the conduct of hostilities ( jus in bello ). These principles cover, for example, the treatment of prisoners of war, civilians in occupied territory, sick and wounded personnel, prohibited methods of warfare and human rights in situations of conflict. This subject was originally termed the laws of war and then the laws of armed conflict. More recently, it has been called international humanitarian law. Although international humanitarian law is primarily derived from a number of international conventions, some of these represent in whole or in part rules of customary international law, and it is possible to say that a number of customary international law principles exist over and above conventional rules, although international humanitarian law is one of the most highly codified parts of international law. Reliance upon relevant customary international law rules is particularly important where one or more of the states involved in a particular conflict is not a party to a pertinent convention. A good example of this relates to the work of the Eritrea–Ethiopia Claims Commission, which noted that since Eritrea did not become a party to the four Geneva Conventions of 1949 until 14 August 2000, the applicable law before that date for relevant claims was customary international humanitarian law. On the other hand, treaty provisions that cannot be said to be part of customary international law will bind only those states that are parties to them.