Summons

Is a summons letter required prior to all disciplinary councils? In my experience, the priesthood leader has already met with the member, who has already agreed to be present, and is already aware of the date, time, and place. Is a summons letter still required?

Handbook 1 Section 6.10.2 doesn't give any exceptions to needing to provide written notice and when submitting the results of the council both the notification letter and the witness of delivery are required documents. So I'd say it's always required.