The Inquisition was the official institution of the medieval Catholic Church that established ecclesiastical judges to investigate and judge divergent opinions and practices that went against what became "systematic Catholic theology." An inquisition was a Catholic judicial procedure in which ecclesiastical judges could initiate, investigate and try cases in their jurisdiction. Popularly, the Inquisition became the name for various medieval and Reformation-era state-organized tribunals whose aim was to combat heresy, apostasy, blasphemy, alchemy, witchcraft, and customs considered to be deviant, using this judicial procedure.