D.C. Code § 49-404
The enrolled militia shall not be subject to any duty except when called into the service of the United States, or to aid the civil authorities in the execution of the laws or suppression of riots. However, if the enrolled militia is called to aid the civil authorities, who already have activated, or will concomitantly activate, the police and fire departments, no member of these departments shall be subject to duty in the militia. Also, if the enrolled militia is called into service of the United States, the chief of the police department and the chief of the fire department shall be entitled to have exempted from call in the militia minimum personnel considered necessary to ensure continued, reasonable police and fire services to the citizens of the District of Columbia.
D.C. Code § 49-404
Establishment of a plan to coordinate operations of the National Guard and the Metropolitan Police Department: Section 3032 of D.C. Law 16-192 provided: "The Mayor is directed to consult with the Commanding General of the National Guard of the District of Columbia to establish a plan whereby the National Guard Reaction Force provided supplemental manpower to the Special Operations Division of the Metropolitan Police Department to assist it in the performance of its duties. The plan shall be implemented within 180 days of April 26, 2006."