The corpse of Pope Formosus was propped up on a throne and then a deacon was called upon to answer questions on behalf of the deceased Pope. The charges that were brought up against Pope Formosus were many of the same charges that were brought against him by Pope John VIII. Pope Stephen also accused Formosus of perjury and performing the duties of a bishop while actually being a layman. The trial was as much of a sham as one would expect when the defendant is a dead body and the body of Pope Formosus was found guilty on all charges.
As punishment, the election of Pope Formosus and any acts he performed as Pope or Bishop were declared to be invalid. In a strange twist this also included the ordination of Pope Stephen (VI) VII as bishop of Anagni. The corpse was also removed of all vestments and the three fingers of the right hand that Pope Formosus had used for blessings were removed. The body was then cast into a grave. However, it was decided that the corpse had not been punished enough, so it was dug up again. This time weights were attached to the feet and the body was thrown in to the Tiber River. The weights were not successful and the body did eventually wash up on the banks of the river. When it did, there were numerous reports of the body performing miracles.
The Cadaver Synod divided Rome and turned many people against Pope Stephen (VI) VII. The people rose up against the Pope and had him deposed and imprisoned. It was sometime in July or August of 897 that Pope Stephen (VI) VII was strangled while he was being held in prison.
In December of 897, Pope Theodore II (Stephen’s successor) convened a synod that annulled the ruling of the Cadaver Synod. He had Formosus’ body reburied in his pontifical vestments in Saint Peter’s Basilica. In 898, Pope John IX held two synods that also annulled the findings of the Cadaver Synod and he even prohibited any future trials of dead people.
For many this should have been the end of it but in 904 Pope Sergius III overturned the synods of Theodore II and John IX and reaffirmed the findings of the Cadaver Synod. He did not punish the body but he did have a laudatory epitaph carved into the tomb of Pope Stephen (VI) VII.