Related Rule
Practice Relating to Rule 156. Definition of War Crimes
Hungary’s Military Manual (1992), in a provision entitled “Grave Breaches (War Crimes)”, contains a list of punishable acts (“among others”). 
Hungary, A Hadijog, Jegyzet a Katonai, Föiskolák Hallgatói Részére, Magyar Honvédség Szolnoki Repülötiszti Föiskola, 1992, p. 90.
In its Decision No. 53/1993, the Constitutional Court of Hungary stated:
In the cases of war crimes and crimes against humanity, such criminal offenses are involved whose classification did not arise as part of the domestic law’s criminal taxonomy, but are deemed to constitute criminal offences by the international community which defines their elements.
These criminal offences – according to the legal standard of international law which evolved since World War II – are not simply offences punishable by the domestic law of most countries. (Therefore, homicide may not, in itself, be classified as a crime against humanity.) Their international status derives from their definition on a supranational level, either on the basis of natural law (invocation of basic principles above and beyond positive law within international law is also a guarantee against arbitrary international agreements), or by reference to the protection of the “foundations of the international community,” or by citing the threat posed by these activities for all of humanity: its commissioners are “enemies of the human race”. Thus, the significance of these offences is too great to permit their punishment to be made dependent upon the acquiescence or general penal law policy of individual nation states. 
Hungary, Constitutional Court of Hungary, Decision No. 53/1993, 13 October 1993, Reasoning, Part IV, § 1.
The Court further stated:
According to the definition of article 13 § (7), (para. 84(g) of the Official Compilation of Penal Regulations in Force, or “OCPRF”), determined by article 8 of 1440/1945 (V.1.) ME decree, of the 81/1945 (II. 5) ME decree elevated to the status of a law by Law VII of 1945 on People’s Tribunals, a person is a war criminal who “in any form commits or has committed, causes or has caused such activities to take place which are capable of undermining or rendering more difficult the post-war peace or cooperation of the nations, or which may create international conflict.”
Such a definition does not appear in a single international convention or document which contains regulations on war crimes or crimes against humanity, and especially not in those which undoubtedly qualify as the repositories of generally recognized principles by the community of nations or international customary law. This substantive law, international humanitarian law, was recapitulated most recently by the document authorizing the International Tribunal to prosecute the war crimes committed in the territory of the former Yugoslavia. The rules of the international humanitarian law embrace: the offense of “grievous violation of rights” defined by the Geneva Convention of August 12, 1949; the violation of the rights and customs of wars, as the rules of the 1907 Hague Convention were interpreted and applied by the Nuremberg International Military Tribunal; the actions made punishable under the Convention on the Prevention and Punishment of the Crime of Genocide, whether committed during war or peace time; and, finally, the crimes against humanity, as contained in the Charter and the judgment of the Nuremberg International Military Tribunal, committed against the civilian population during international or domestic armed conflicts. Within these broad categories, the documents and pertinent conventions contain the specific definitions of the behaviours constituting the offences. In this constitutional review procedure the Constitutional Court refrained from addressing whether the definition contained in article 1 of the Law is unconstitutional for lack of definitiveness, but holds that its general definition cannot be classified as war criminal behaviour according to the international legal definitions on such offences. 
Hungary, Constitutional Court of Hungary, Decision No. 53/1993, 13 October 1993, Reasoning, Part V, § 2.