Thus Innocent III, while ever conscious of the popular distaste for the same man being both accuser and judge, went along with the legal fiction of permitting ‘the public outrage’ to be sufficient for summoning a person to an accounting. But this was only a halfway measure that really did not solve the problem of bringing notorious persons to the bar. For once the popular clamor of the synodal witness had brought the person to court, they then withdrew; they had no part in the examination of the accused. It still seemed as if the judge and the accuser were the same, despite this legal fiction. What was needed was for the synodal witness, who according to Canon Six of the Council, was to investigate the evil report and notify the bishop, to continue on as an active participant in the trial.
This step, however, would not be taken until a score of years later when the ‘inquisitorial procedure’ was adapted by Pope Gregory IX (1227-1241) as a specific institution (the Inquisition) to deal with heresy. As the Inquisitor under the new mandate from Gregory IX organized the process for investigating heresy and heretics, he found it advantageous to appoint minor officials to make the original inquiries and then to assist him in the actual process of the trial. Out of this practice grew the office of ‘minister of the inquisition,’ who was really basically concerned with the investigation of heresy and with prosecuting the accused before the inquisitorial tribunal itself. From this auxiliary office developed the Promoter of Justice in church courts, whose duty it was to investigate wrong doing and to prosecute offenders. In this same century emerged the Grench office of procurateur de rio, and eventually states’ attorneys, precursors of modern day district attorneys.
Thus the Church substituted the inquisitorial procedure for the defective accusatory process. A rational inquiry was now introduced as the ordinary method of weighing the evidence and of deciding the guilt or innocence of an accused person. Moreover a designated official now assumed the responsibility for investigating and prosecuting alleged offenders. Both of these developments found their way into the legal systems of continental Europe. Indeed the ‘enquete’ of Louis IX of France is one of the glories of his reign, and a milestone in legal history. The inquisitorial procedure owers its modern day reputation to its association with the tribunal of the Inquisition, with which it has been mistakenly identified.
The inquisitorial procedure, then, was designed to remedy the deficiencies of the traditional accusatory method which made the detection and prosecution of criminal offenses dependent upon private initiative. The inquisition evolved by the Church to deal more effectively with abuses by the clergy was shortly adapted as a special agency in response to the exigencies engendered by the growth and spread of heresy. The Inquisition as an institution as well as a legal method of procedure was a court of exception, of extraordinary and summary procedure, in the face of a virulent and pressing danger.
Albert Shannon, The Medieval Inquisition (1991)