The Zugarramurdi witchcraft trials were hel under the inquisition and the appointed inquisitor Don Juan Valle Alvarado. Alvarado spent several months gathering testimony. which cast suspicion of witchcraft crimes upon nearly 300 persons, not counting children. The testimonies taken were never questioned. Alvarado determined at least 40 of the suspects were guilty so he had them arrested and taken to be trialed before three judges.

Of the 40 accused witches, 18 confessed and tearfully asked for mercy, and were reconciled with teh church. 6 were burned at the stake. 5 died during the trial. The remaining 11 were presumed to be innocent or not convicted.