An attempt has been made to produce an analysis of the judicial reinterpretation given by the prosecution team, led by Robert H. Jackson at the Nuremberg trial in 1946 against the National Socialist leaders. To achieve this objective, three main ideas have been identified that answer the research question posed on the ontological foundations of the principle of legality.The hermeneutic methodology applied, on the basis of the documentary review of the judicial process in Nuremberg, will allow an analysis to be carried out on the development of general legality. A pedagogical explanation will be produced that allows us to glimpse how the fiscal team manages to reinterpret the natural essence of legality and reformulate the variables that define it for the generation of the imputability of the defendants in Nuremberg.