This study examines Inquisitorial trials against health care practitioners from 1667 to 1697 in the largest cities of colonial Spanish America: Lima, Cartagena de Indias and Mexico. It argues that the victims of medical malpractice employed available political and ideological mechanisms of the Inquisition, using accusations such as sorcery, witchcraft, heresy or Lutheranism, as a means to claims justice. At the same time, it argues that the Inquisition tried to identify alternative levels of knowledge and distinguish skillful health care professionals from impersonators, which require a systematic inquiry into the healing process. In particular, the trials against some folk healers, and questions made during their judicial process, suggest that Inquisition have a scientific approach. On the whole, because some healers were sentenced to work in hospitals, while some trained foreign professionals were sentenced to monasteries where they learned Spanish, demonstrates that the Inquisition formally included healers and foreigners into colonial society.