150. (1) A member of the Garda Síochána not below the rank of superintendent may appoint in writing a person (other than a member of the Garda Síochána) to be an authorised person for the purposes of Parts 3, 5 and 6 (in this Act called an “authorised person”).

(2) An authorised person may perform the functions conferred on an authorised person by Parts 3, 5 and 6.

(3) An authorised person shall be furnished with a warrant of appointment and shall, when performing a function under Parts 3 and 6, if requested by a person affected, produce the warrant of appointment or a copy of it to the person.

(4) An appointment to be an authorised person under this section may be revoked in writing by a member of the Garda Síochána not below the rank of superintendent.