309.1. A tenant whose rental unit fails to meet the standards of habitability established by this chapter may:
(a) Withhold rent proportional to the reduction in value caused by the deficiency, pending restoration of habitability;
(b) Repair the deficiency and deduct the reasonable cost from rent, subject to the limitations of D.C. Code § 42-3201;
(c) File a complaint with the DC Department of Buildings (DCRA) or the Rental Housing Commission requesting an inspection and enforcement action;
(d) Bring a civil action for damages, including the difference between the fair rental value of the unit as warranted and its value in the condition as delivered.