D.C. Code § 49-407
A reserve corps of the National Guard of the District of Columbia is hereby organized, to consist of honorably discharged officers and men of the Army, the Navy, the Air Force, and the Marine Corps of the United States, honorably discharged officers and men of the organized militia of any state or territory who are residents of the District of Columbia, and honorably discharged members of the National Guard of the District of Columbia, whose military training and physical condition shall conform to the standard determined by regulations to be promulgated by the President of the United States; provided, that the term of enlistment in the reserve and the military duties and obligations required of reservists shall be determined by regulations to be promulgated by the President of the United States; provided further, that when called out for military duty, reservists shall receive the same pay and allowances as officers and men of like grade on the active list of the National Guard of the District of Columbia.
D.C. Code § 49-407