Practice Relating to Rule 161. International Cooperation in Criminal Proceedings
New Zealand’s Military Manual (1992) states with respect to the prosecution of alleged war criminals:
If the Party concerned does not institute proceedings against offenders, it may, subject to the provisions of its own law, hand such persons over for trial by any party to the Conventions which has made out a prima facie case. This reference to the local law makes the procedure subject to local extradition legislation and some countries are likely to argue that war criminals acting on governmental instruction are political offenders immune from extradition. This argument was expressly rejected by the Ghana Court of Appeal in Ex p. Schumann
(1949) … when put forward to contest an extradition application in respect of a doctor involved in the extermination programme at the Auschwitz concentration camp. [The 1977 Additional Protocol I] Art. 88 requires the parties to assist one another in connection with grave breaches, including cooperation in matters of extradition.