D.C. Code § 16-1502: Service of summons.

(a)

The summons provided for by section 16-1501 shall be served at least 14 days before the day fixed for the initial hearing of the action. If the defendant has left the District, or cannot be found, the summons may be served by delivering a copy of the summons to the tenant, or by leaving a copy with some person above the age of 16 years residing on or in possession of the premises, or by posting a copy of the summons on the premises where it may be conveniently read.

(b)

(1)

If the summons is posted on the premises, a copy of the summons shall be mailed first class U.S. mail, postage prepaid, to the premises sought to be recovered, addressed in the name of the person known to be in possession of the premises, or, if unknown, addressed in the name of the person occupying the premises, within 3 calendar days of the date of posting.

(2)

If a summons is served by posting a copy on the premises, a photograph of the posted summons must be submitted to the court. The photograph must have a readable timestamp that indicates the date and time when the summons was posted.