Md. Code, Transportation § 21–601

(a) If the driver of a vehicle intends to turn right at any intersection, he shall approach the intersection and make the right turn as close as practicable to the right-hand curb or edge of the roadway.

(b) If the driver of a vehicle intends to turn left at any intersection or crossover, he shall approach the intersection or crossover in the extreme left-hand lane lawfully available to traffic moving in the same direction.

(c) If the driver of a vehicle intends to turn left at any intersection or crossover, the driver shall, after entering the intersection or crossover, make the left turn so as to leave the intersection in a lane lawfully available to traffic moving in the same direction on the roadway being entered.

(d) (1) The State Highway Administration or any local authority may place a traffic control device at or near any intersection in its jurisdiction and, with it, direct that vehicles turning at the intersection travel a course different from one specified in this section.

(2) At an intersection where a traffic control device is placed under this subsection, the driver of a vehicle may not turn otherwise than as directed by the device.