Maryland Criminal Law Section 4-102

      (a)      This section does not apply to:

            (1)      a law enforcement officer in the regular course of the officer's duty;

            (2)      a person hired by a county board of education specifically for the purpose of guarding public school property;

            (3)      a person engaged in organized shooting activity for educational purposes; or

            (4)      a person who, with a written invitation from the school principal, displays or engages in a historical demonstration using a weapon or a replica of a weapon for educational purposes.

      (b)      A person may not carry or possess a firearm, knife, or deadly weapon of any kind on public school property.

      (c)      (1)      Except as provided in paragraph (2) of this subsection, a person who violates this section is guilty of a misdemeanor and on conviction is subject to imprisonment not exceeding 3 years or a fine not exceeding $1,000 or both.

            (2)      A person who is convicted of carrying or possessing a handgun in violation of this section shall be sentenced under Subtitle 2 of this title.