D.C. Mun. Regs. tit. 3, § 802
802.1 The Executive Director, or his or her designee, shall make determinations on the validity of ballots.
(a) Any election official who is uncertain whether a ballot is partially or totally invalid, he or she shall refer the ballot to the Executive Director for a determination.
(b) Any poll watcher or election observer who is uncertain whether a ballot is partially or totally invalid may refer the ballot to the Executive Director for a determination.
802.2 Except as provided in this section, only official ballots shall be valid and counted.
802.3 Pursuant to Chapter 7 of this Title, if a qualified uniformed or overseas elector chooses to use a Federal Write-In Absentee Ballot, or chooses to electronically submit his or her ballot, it shall be treated as an official ballot and deemed valid.
802.4 If a precinct was authorized by the Board to use reproductions of official paper ballots because of an emergency, the reproductions shall be considered official ballots and deemed valid.
802.5 If a ballot marked "Challenged" or "Special" is placed in a ballot box and received at a counting place other than in a Special Ballot Envelope, it shall be deemed invalid.
SOURCE: Final Rulemaking published at 27 D.C. Reg. 1836 (May 2, 1980), incorporating the text of Proposed Rulemaking published at 27 D.C. Reg. 1222, 1242 (March 21, 1980); and further amended by Final Rulemaking published at 30 D.C. Reg. 5289, 5299 (October 14, 1983); as amended by Final Rulemaking published at 51 D.C. Reg. 7426 (July 30, 2004); as amended by Final Rulemaking published at 51 D.C. Reg. 5063 (May 14, 2004); as amended by Notice of Emergency and Proposed Rulemaking published at 57 DCR 7705 (August 20, 2010)[EXPIRED]; as amended by Notice of Final Rulemaking published at 57 DCR 11149, 11152 (November 26, 2010).