Questions and answers:
Applicability of Additional Protocol I in different types of conflict
In international armed conflicts, I understand that the four Geneva Conventions, as well as Additional Protocol I, are applicable. However, it is not clear to me if there are any particular requirements for Additional Protocol I to apply (as I understand is the case for Additional Protocol II) or if it is always valid for all international armed conflicts.
Regional Director, INGO
With regard to international armed conflict (IAC), governed by the four Geneva Conventions of 1949 and by Additional Protocol I, the definition of IAC is the same for the purpose of the application of these treaties and Additional Protocol I does not contain specific requirements. Article 1 para. 3 of Additional Protocol I provides that it "supplements the Geneva Conventions of 12 August 1949 for the protection of war victims, [and] shall apply in the situations referred to in Article 2 common to those Conventions." This means it applies to armed conflicts between two or more High Contracting Parties to those treaties (similarly IAC has been defined by the International Criminal Tribunal for the former Yugoslavia (ICTY) in the Tadic case as "resort to armed force between States"). The only specific sub-categories of IAC considered by the Geneva Conventions and/or by the Additional Protocol I requiring specific criteria are situations of occupation (which gives rise to the application of the norms of the Law of Occupation) and wars of national liberation.