Until the development of the Catholic Medieval Inquisition in the 12th century, the legal systems used in medieval Europe generally relied on the adversarial system to determine whether someone should be tried and whether a person was guilty or innocent. Under this system, unless people were caught in the act of committing crimes, they could not be tried until they had been formally accused by their victim, the voluntary accusations of a sufficient number of witnesses, or by an inquest (an early form of grand jury) convened specifically for that purpose. A weakness of this system was that, because it relied on the voluntary accusations of witnesses, and because the penalties for making a false accusation were severe, victims and would-be witnesses could be hesitant to make accusations to the court, for fear of implicating themselves. Because of the difficulties in deciding cases, procedures such as trial by ordeal or combat were accepted.