10. Upon request by one of the parties, the Commission shall summon a witness to declare what he knows, produce a document, or both, unless the Commission is of the opinion that the application for a summons is irrelevant on the face of it.
The subpoena shall be served at least 5 clear days before the hearing, or at least 10 clear days before the hearing if it is served on a minister, a deputy minister or the executive officer of a body.
In an emergency, the Commission may reduce the time for service on the subpoena.