D.C. Mun. Regs. tit. 18 § 2203
The driver of a vehicle intending to turn at an intersection shall do so as set forth in this section, unless a different method of turning is directed by signs, signals or markings at the intersection.
Where a specific method of turning at an intersection is indicated by buttons, markers, or signs, turns shall be made in accordance with the directions of those signs, signals or markings.
Both the approach for a right turn and a right turn shall be made as close as practicable to the right-hand curb or edge or the roadway.
Approach for a left turn from a two-way street into a two-way street shall be made in that portion of the right half of the roadway nearest the center line of the roadway, and after entering the intersection the left turn shall be made so as to leave the intersection to the right of the center line of the roadway being entered.
Approach for a left turn from a two-way street into a one-way street shall be made in that portion of the right half of the roadway nearest the center line of the roadway and by passing to the right of the center line where it enters the intersection.
Approach for a left turn from a one-way street into a two-way street shall be made in that portion of the roadway as close as practicable to the left-hand curb or edge of the roadway. After entering the intersection the left turn shall be made so as to leave the intersection to the right of the center line of the roadway be engendered.
Where both streets or roadways are one-way, both the approach for a left turn and a left turn shall be made as close as practicable to the left-hand curb or edge of the roadway.
No left turn shall be made from a "service" roadway; Provided, that a vehicle turning from "service" roadway into a "through" roadway so as to proceed in the same general direction shall not be considered to be making a left turn.
At intersections where "cut-off" roadways have been provided to facilitate a right turn, all vehicles emerging from such "cut-off" roadways shall turn to the right.
On streets designated under this subtitle as UNBALANCED TRAFFIC LANES, and during the hours provided in the applicable section for such streets, the word "centerline" as used in this section, shall mean the line between the two (2) directions of flow on such streets during the designated hours.
No person shall turn a vehicle at an intersection unless the vehicle is in proper position upon the roadway, as required in this section.
D.C. Mun. Regs. Tit. 18, § 2203