Md. Code, Pub. Safety § 7-402

(a) A person may not willfully interfere with or obstruct a firefighter, a rescue squad member, or emergency services personnel while the firefighter, rescue squad member, or emergency services personnel: (1) is fighting a fire, performing emergency services, or proceeding to a fire or other emergency; or (2) is dispatched on a call for emergency services. (b) A person may not, with fraudulent design on person or property, falsely represent that the person is a member of a career or volunteer fire department, rescue squad, or emergency services unit of the State or a county or municipal corporation of the State. (c) A person may not have, use, wear, or display without proper authority, for the purpose of deception, a uniform, shield, button, ornament, identification, or shoulder patch, or a simulation or imitation of these articles, adopted by a career or volunteer fire department, rescue squad, or emergency services unit. (d) A person who violates this section is guilty of a misdemeanor and on conviction is subject to imprisonment not exceeding 3 years.