From our brief examination of the current procedure in force in the inquisitorial tribunals and in the secular criminal courts of the thirteenth and fourteenth centuries in France, the evidence appears to warrant the following conclusions. The inquisitorial tribunal was a court of exception, and because of the nature of the crime of heresy and the necessity for the protection of deponents, certain refinements of the ordinary juridical processes were withdrawn. The names of the witnesses were withheld from the accused, but the full transcript of the testimony was given to the accused. In secular criminal trials in France during the same period, however, it appears that in the highest court of the land and quite generally in the pays de droit coutumier not only the names of the witnesses but even the depositions themselves were withheld from the defendant. In point of fact France still retains certain of these features in her present criminal procedure in the periode d’instruction. At the same time, it must be said that practice varied in ordinary civil trials, and in the pays de droit ecrit as compared with the pays de droit coutumier.
Albert Shannon, “The Secrecy of Witnesses in Inquisitorial Tribunals and in Contemporary Secular Criminal Trials”, Essays in Medieval Life and Thought: Presented in Honor of Austin Patterson Evans (1965)