D.C. Mun. Regs. tit. 17, r. 17-4121
If, because of accident, sickness, or other good cause, a respondent fails to receive a notice of a hearing or fails to appear for a hearing, the respondent may, within fifteen (15) days from the date of service of the decision, apply to the board to reopen the hearing.
If a board finds good cause to reopen a hearing, the board shall, as soon as practicable, fix a time and place for a hearing and give the respondent and the Corporation Counsel notice of the hearing.
A board may also reopen a hearing for any other cause sufficient to it; Provided, that no appeal is pending before a court or has been decided by a court.
A decision of a board to reopen a hearing shall be entirely within the discretion of the board and shall not be subject to review.
D.C. Mun. Regs. tit. 17, r. 17-4121