The paper is aimed at investigating the set of structures and institutions well known with the term “Inquisition”. To this end, the historical evolution of the Inquisition in Italy will be analyzed, examining its organizational structure and comparing it with the Spanish and Portuguese one. Such a research can be an
opportunity to provide a contribution to the most precise framing of the trial structures labeled with the term “Inquisition”. For this purpose, the investigation will be specifically devoted to the examination of the inquest and investigative institutions present in canon law in order to highlight the peculiar physiognomic
aspects and the close connection with institutions present in the modern criminal trial. Besides, the research is aimed at highlighting the double purpose of the inquisitive structures of that age. On the one hand , the acknowledgement, by the defendant, of the error of charging him; on the other hand the consequent
devaluation, on the ideological level, of the professed opinion, in order to show how the system of relations between the prosecutor, the defendant and the judge was aimed not so much at imposing a penalty on the guilty, but to ensure the victory of the good on the wrong.


Keywords: Ecclesiastical Justice; Inquisition; Purpose of the Penalty.