Where a person is incapable, by reason of mental disorder within the meaning of the Mental Health (Northern Ireland) Order 1986, of managing and administering his property and affairs, his controller or (if no controller is acting for him) any person authorised in that behalf may, under an order of the High Court or (as the case may be) the court[F2 or, in the case of a reference to the Lands Tribunal, that Tribunal], represent him for all or any of the purposes of this Act.]