DURING THE NUREMBERG TRIALS after World War II, several Nazis, including top German generals Alfred Jodl and Wilhelm Keitel, claimed they were not guilty of the tribunal's charges because they had been acting at the directive of their superiors.
Ever since, this justification has been popularly known as the "Nuremberg defense," in which the accused states they were "only following orders."
The Nuremberg judges rejected the Nuremberg defense, and both Jodl and Keitel were hanged. The United Nations International Law Commission later codified the underlying principle from Nuremberg as "the fact that a person acted pursuant to order of his Government or of a superior does not relieve him from responsibility under international law, provided a moral choice was in fact possible to him."
This is likely the most famous declaration in the history of international law and is as settled as anything possibly can be.