D.C. Mun. Regs. tit. 4, r. 4-519
No employer shall discharge, suspend, refuse to hire or promote an individual, or subject an individual to different terms, conditions, and privileges of employment because of his or her sexual orientation.
Employers shall not dismiss, suspend, refuse to hire or promote any person on the basis of an employee's open or suspected sexual orientation and nonconformity to the stereotyped characterization of masculine or feminine behavior.
Employers shall apply the same standards of acceptable on-the-job conduct to all employees regardless of sexual orientation, and the same procedures and standards for discipline and dismissal employed shall be applied equally to all, regardless of sexual orientation.
Questions by an employer which compel answers concerning the sexual orientation of an employee shall be considered prima facie evidence of discrimination.
Employers or employment agencies shall not collect or disseminate information about the sexual orientation or practices of employees.
The use of derogatory or insulting language about or directed at an employee on the premises by the employer and other employees because of an employee's open or suspected sexual orientation shall be considered prima facie evidence of discrimination.
D.C. Mun. Regs. tit. 4, r. 4-519