Instrument of Degradation is a written list of charges against a person who holds a title or office that has religious significance. Notable uses include ceremonies that removed members from the Order of the Garter.
Persons who have been the subject of an Instrument of Degradation
The 2nd Duke of Ormonde was the last person to be degraded from the Order of the Garter in a formal ceremony. An Instrument of Degradation was read in St. George's chapel while his crest was removed in 1716.
References
Instrument of Degradation Wikipedia(Text) CC BY-SA