Regulation 23 Summoning of witnesses
The President may by summons require any person in England and Wales to attend as a witness at a hearing of an appeal at such time and place as may be specified in the summons and at the hearing to answer any questions or produce any documents or other material in his custody or under his control which relate to any matter in question in the appeal:
Provided that—
no person shall be compelled to give any evidence or produce any document or other material that he could not be compelled to give or produce at a trial of an action in a Court of law;
in exercising the powers conferred by this regulation, the President shall take into account the need to protect any matter that relates to intimate personal or financial circumstances or consists of information communicated or obtained in confidence;
no person shall be required to attend in obedience to such a summons unless he has been given at least 5 working days' notice of the hearing or, if less than 5 working days, he has informed the President that he accepts such notice as he has been given; and
no person shall be required in obedience to such a summons to attend and give evidence or to produce any document unless the necessary expenses of his attendance are paid or tendered to him.