The Nuremberg principles were a set of guidelines for determining what constitutes a war crime. The document was created by the International Law Commission of the United Nations to codify the legal principles underlying the Nuremberg Trials of Nazi party members following World War II.
"Any person who commits an act which constitutes a crime under international law is responsible therefore and liable to punishment."
"The fact that internal law does not impose a penalty for an act which constitutes a crime under international law does not relieve the person who committed the act from responsibility under international law."
"The fact that a person who committed an act which constitutes a crime under international law acted as Head of State or responsible government official does not relieve him from responsibility under international law."
"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 principle could be paraphrased as follows: "It is not an acceptable excuse to say 'I was just following my superior's orders'".
Previous to the time of the Nuremberg Trials, this excuse was known in common parlance as "Superior Orders". After the prominent, high-profile event of the Nuremberg Trials, that excuse is now referred to by many as the "Nuremberg Defense". In recent times, a third term, "lawful orders" has become common parlance for some people. All three terms are in use today, and they all have slightly different nuances of meaning, depending on the context in which they are used.