D.C. Code § 32-1331.10: Retaliation prohibited.

(a)

An employer may not discriminate in any manner or take adverse action against any person because the person:

(1)

Makes an oral or written complaint with the employer or the Mayor alleging that the employer violated any provision of this subchapter or any rule issue pursuant to this subchapter;

(2)

Brings an action or initiates a proceeding involving a violation of this subchapter;

(3)

Testifies in an action authorized under this subchapter or a proceeding involving a violation of the provisions of this subchapter or any rule issued pursuant to this subchapter; or

(4)

Assists in an investigation by providing information to a litigant in a civil action, the Mayor, or another agency in proceedings as provided by [this] subchapter.

(b)

(1)

A person who believes that an employer has discriminated in any manner or taken adverse action against the person in violation of this subchapter may submit to the Mayor a written complaint, signed by the complainant, that alleges the discrimination.

(2)

Upon receipt of a complaint, the Mayor shall conduct an investigation.