D.C. Mun. Regs. tit. 1, r. 1-2929
An Administrative Law Judge may consolidate (join) two (2) or more petitions if they present identical or similar issues, involve the same rental unit or housing accommodation, or involve other circumstances in which consolidation would be expedient and would not prejudice the parties. A party may file a motion to consolidate, or an Administrative Law Judge may consolidate, cases on his or her own motion.
If the Administrative Law Judge determines that the issues raised in a petition or request may affect other tenants or all tenants in the housing accommodation, the Administrative Law Judge may expand the scope of the proceeding to include all affected tenants.
Before expanding the scope of the proceeding, the Administrative Law Judge shall provide notice to the affected tenants and the housing provider or owner.
Notice under §§ 2929.3 shall state the issues to be decided and shall advise the tenants that they have a right to participate in the proceedings and that any decision shall be binding on them.
Tenants and the housing provider or owner may present arguments in support of or opposition to expanding the scope of the proceeding.
A party may amend a petition to add additional allegations after the petition has been transferred to OAH, but before the hearing concludes, by moving to amend the petition with the presiding Administrative Law Judge. The motion shall state the allegations to be added and the factual basis for those allegations. No written motion to amend shall be considered unless it recites that the movant sought to obtain the consent of parties affected, and that the consent was granted or denied, including the identity of the party or parties who declined to consent. If the movant does not obtain a response from the opposing party, the movant shall demonstrate that the movant made a good faith effort in accordance with §§ 2817.5.
In determining whether a motion to amend a petition should be granted, the Administrative Law Judge shall consider:
D.C. Mun. Regs. tit. 1, r. 1-2929