Hearing of applications: Authority must hear applicants and may call evidence or seek law officer opinions before advance rulings. The Authority must provide a hearing to the applicant or authorised representative when rejection is proposed or the applicant seeks to be heard, and may hear the Principal Commissioner or Commissioner if necessary before issuing an advance ruling; it may adjourn hearings on appropriate conditions, call any person to depose or produce documents necessary for decision-making, and refer important questions of law to a Central Government law officer including the Attorney-General or Solicitor-General for an opinion under the extant procedure.