D.C. Code § 14-104: Testimony of nonresident witnesses for use in Superior Court.

If the testimony of nonresident witnesses is required by either party to a civil action or proceeding in the Superior Court of the District of Columbia the Court, upon motion designating the names of the witnesses, may appoint an examiner to take their testimony, to whom it shall issue a commission. The testimony shall be taken as provided in the rules of the Superior Court.