Each witness who shall appear before the Commission or the presiding officer pursuant to an order for deposition or subpoena, shall receive the same fee for attendance and mileage as is currently paid to witnesses by the District of Columbia Superior Court.
No witness subpoenaed by the Commission at the request of any party shall be entitled to compensation for attendance or travel unless the Commission shall certify that the witnesses testimony was material to the matter investigated, and that attendance as a witness was reasonably necessary.
D.C. Mun. Regs. tit. 15, r. 15-136