D.C. Mun. Regs. tit. 16, r. 16-1514
A party may serve upon any other party a written request for an admission, for the purposes of the pending action only, of the truth of any matters set forth in the request that relate to statements of fact or opinions, or of the application of law to fact, including the genuineness of any documents described in the request.
Copies of documents which are being requested to be admitted shall be served with the request unless they have been or are otherwise furnished or made available for inspection and copying.
Each matter for which an admission is requested shall be separately set forth.
The matter shall be admitted unless, within twenty (20) days after service of the request, the party to whom the request is directed files a written answer or objection addressed to the matter. The answers or objections shall be signed by the party or his or her attorney.
Detailed reasons shall be stated for any objection made.
The answer shall specifically admit or deny the matter, or set forth in detail the reasons why the answering party cannot truthfully admit or deny the matter.
An answering party may not give lack of information or knowledge as a reason for failure to admit or deny unless he or she states that he or she has made reasonable inquiry and that the information known or readily made obtainable by him or her is insufficient to enable him or her to admit or deny the matter. The statement shall be supported by an affidavit setting out the efforts that were made to locate the needed information.
A party who considers that a matter for which an admission has been requested presents a genuine issue for trial may not, on that ground alone, object to the request. The party may deny the matter or set forth reasons why the matter cannot be admitted or denied.
D.C. Mun. Regs. tit. 16, r. 16-1514