D.C. Mun. Regs. tit. 31, r. 31-331
If any document initiating or filed in a proceeding is not in substantial conformity with the rules applicable to its contents, or is otherwise insufficient, the Chairperson or the hearing panel may, on his or her or its own initiative, or on motion of any party, strike or dismiss the document, or require its amendment.
If properly amended, a document shall be made effective as of the date of original filing, but the time prescribed for the filing of any further responsive document directed towards the amended document shall be computed from the date of the filing of the amendment.
At any time more than ten (10) days prior to the date of hearing, a party may amend its pleading by filing the amended pleading with the Chairperson and by serving copies on the other parties. After that time, amendment shall be allowed at the discretion of the Chairperson.
Where amendment to an answerable pleading has been allowed, the Chairperson shall allow the adverse party a reasonable time to answer.
A party may withdraw a pleading only upon approval of the Chairperson.
D.C. Mun. Regs. tit. 31, r. 31-331