D.C. Code § 49-102: Prescribing drills.

The Commanding General shall prescribe such stated drills and parades as he may deem necessary for the instruction of the National Guard, and may order out any portion of the National Guard for such drills, inspections, parades, escort, or other duties, as he may deem proper. The commanding officer of any regiment, battalion or company may also assemble his command, or any part thereof, in the evening for drill, instruction, or other business, as he may deem expedient; but no parade shall be performed by any regiment, battalion, company, or part thereof, without the permission of the Commanding General.