However, bearing in mind the development of international criminal law, the obligation could be said to be customary with regard to international crimes such as genocide, crimes against humanity and war crimes.
但是，考虑到国际刑事法的发展，可以说，对灭绝种族罪、危害人类罪和战争罪等国际罪行而言，该义务来自习惯法。