reg 17 Rights of audience
In any proceedings before the court, any of the following persons may address the court— (a) the legal representative of a party to proceedings; (b) the person to whom proceedings relate, if that person is entitled to be present or has obtained the leave of the court to be present during proceedings, with the leave of the court and if not otherwise represented; (c) any other party to proceedings, with the leave of the court and if not otherwise represented; and (d) where the court is sitting at a place outside the United Kingdom, any other person allowed by leave of the court to appear on behalf of a party to the proceedings.