Some peremptory norms define criminal offences which are considered to be enforceable against not only states, but individuals as well. This has been increasingly accepted since the Nuremberg Trials (the first enforcement in world history of international norms upon individuals) and now might be considered uncontroversial. However, the language of peremptory norms was not used in connection with these trials – rather the basis of criminalisation and punishment of Nazi atrocities was that civilisation could not tolerate their being ignored, because it could not survive their being repeated.

So, if I understand correctly, at Nuremberg “peremptory norms” overrode whatever good-faith legal assurances the defendants had that their behavior would be legal. A very interesting and compelling principle of law.

good night all.