Article 17 Absence of justice entitled to preside
The justices present may appoint one of their number to preside in court to deal with any case in the absence of a justice entitled to preside under rule 16, if—
(a)
before making such an appointment, the justices present are satisfied as to the suitability for this purpose of the justice proposed; and
(b)
the justice proposed has completed or is undergoing a course of instruction for chairmanship in accordance with arrangements approved by the Lord Chancellor under section 64 of the 1997 Act, unless by reason of illness, circumstances unforeseen when the justices to sit were chosen, or other emergency no such justice is present.