Règle correspondante
Norway
Practice Relating to Rule 156. Definition of War Crimes
Norway’s Act on the Punishment of Foreign War Criminals (1946) provided that acts forbidden by Norwegian criminal law which had been committed against Norwegian nationals or interests or in Norway during the Second World War and were in violation of the laws and customs of war could be tried according to Norwegian law. 
Norway, Act on the Punishment of Foreign War Criminals, 1946.
In its judgment in the Repak case in 2010, Norway’s Court of Appeal stated:
Not all violations of international humanitarian law are to be regarded as war crimes. The starting point is that the violation must involve a serious breach of a rule of international law that protects substantial values, and that causes individual criminal responsibility according to either international customary law or treaty based law. 
Norway, Borgarting Lagmannsrett (Court of Appeal), Repak case, Judgment, 12 April 2010, p.15, section 3.