Maryland Code, TRANSPORTATION 21-207
(b) While a funeral procession is proceeding through a red signal as permitted by this section, a vehicle that is not in the procession may not enter the intersection, even if it is facing a green signal, unless it can do so without crossing the path of the procession. When the red signal changes to green while the funeral procession is still within the intersection, a vehicle facing a green signal may proceed, but the funeral procession has the right-of-way.
(c) The driver of a vehicle in a funeral procession does not have any privilege granted in this section unless:
(1) The headlights of the vehicle are turned on; and
(2) Subject to § 22-221(g) of this article, the warning lamps of the vehicle are flashing.