45.— For the purposes of any adjudication under this Part, a parliamentary legal costs adjudicator may—
(a) examine under oath any party to such adjudication, and any witnesses who may be examined in relation thereto,
(b) receive any sworn affidavit, or
(c) call for the production of any document in the possession or control of any party to such adjudication relevant to the matters of such adjudication.