(a) Except to the extent required for the disposition of ex parte matters as authorized by law, the person presiding over an evidentiary hearing may not:

1. (1) Consult a person or party on a fact in issue, unless on notice and opportunity for all parties to participate; or
2. (2) Be responsible to or subject to the supervision or direction of an employee or agent engaged in the performance of investigative or prosecuting functions for the Commission.