District of Columbia Code Division V. Local Business Affairs § 32-902. Use prohibited; exceptions.

(a) No employer or prospective employer shall administer, accept or use the results of any lie detector test in connection with the employment, application or consideration of an individual, or have administered, inside the District of Columbia, any lie detector test to any employee, or, in or during any hiring procedure, to any person whose employment, as contemplated at the time of administration of the test, would take place in whole or in part in the District of Columbia.

(b) The provisions of this section shall not apply to any criminal or internal disciplinary investigation, or pre-employment investigation conducted by the Metropolitan Police, the Fire Department, and the Department of Corrections; provided that any information received from a lie detector test which renders an applicant ineligible for employment shall be verified through other information and no person may be denied employment based solely on the results of a pre-employment lie detector test.