The trials conduced in the medieval inquisition were conducted in absolute secrecy. The defendants were given the right to an attorney, but many lawyers would not take on such a client. Should the accused be found guilty of heresy (as they most often were), then the attorney would lose his license to practice law. A papal bull issued in 1254 stripped defendants of the right to an attorney, but granted those found guilty the right to appeal their convictions to the Pope.

The accused were not allowed to know whom their accusers were, but were instead invited to name any individuals that may have a “mortal hatred” against them. If the defendant could accurately identify their accuser, the defendant was set free, and the case dismissed.

Confessions made under torture were not admissible in court, but this rule was frequently overlooked. The same papal bull in 1254 that repealed the right to an attorney also granted the right to induce torture upon the accused. Before the issuing of this bull, the inquisitors frequently threatened torture in the hopes to attain a confession.

The accused were never outwardly told their formal charges. Instead, the inquisitors forced the accused to guess. If the accused could guess their correct charges and they confessed, they were charged with a mild first offense. Naturally, this practice was implemented in an effort to indict the accused on several more charges.

During the trial, a secretary instructed to take detailed notes of every utterance from the accused accompanied the chief familiar.