Maryland Code, Transportation § 22-403

(a) Every motor vehicle shall be equipped with at least one mirror located to reflect to the driver a view of the highway for a distance of at least 200 feet to the rear of the vehicle.

(b) Every motor vehicle registered in this State shall be equipped with an outside mirror on the driver's side located to reflect to the driver a view of the highway for a distance of at least 200 feet to the rear of the vehicle and along the driver's side of the vehicle. This subsection does not apply to motorcycles, which are governed by subsection (c) of this section.

(c) Every motorcycle shall be equipped with two rearview mirrors, one each attached to the right and left handlebars, which shall meet applicable federal motor vehicle safety standards.

(d) Where the view through the inside rearview mirror is obstructed, two outside rearview mirrors are required.