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The Cadaver Synod, or Synod of the Corpse, was a synod held in Rome in 897 by Pope Stephen VI against his predecessor, Pope Formosus. It was the first papal trial of a dead pope, and one of the most controversial events in the history of the papacy. The synod was called to investigate charges against Formosus that he had committed perjury, simony, and other crimes during his pontificate.