Md. Code, Transportation § 21–1407

(a) The driver of a vehicle may not stop, stand, or park the vehicle on any Authority highway, except:

(1) If necessary to avoid injury or damage to any person or property;

(2) In compliance with the lawful direction of an authorized employee of the Authority highway;

(3) At a designated area for the transaction of business at an Administration building; or

(4) If the vehicle is disabled or involved in an accident, in which case the vehicle shall be moved, if possible:

(i) To the shoulder of the roadway;

(ii) Adjacent to the emergency walkway on a bridge; or

(iii) As otherwise directed by a patrol officer.

(b) Notwithstanding § 25–201(b) of this article, the Maryland Transportation Authority may adopt regulations governing the removal of vehicles left unattended for 12 or more hours on any Authority highway.