Maryland Code, Criminal Law § 10-609

(a) Except as provided in subsections (b) and (c) of this section, if an officer of a humane society sees a person committing a misdemeanor that involves cruelty to an animal, the officer shall arrest and bring before the District Court the person committing the misdemeanor.

(b) In Calvert County, if an officer of a humane society or an animal control officer appointed by the County Commissioners or the County Commissioners' designee sees a person committing a misdemeanor that involves cruelty to an animal, the officer shall arrest and bring before the District Court the person committing the misdemeanor.

(c) In Baltimore County, the Baltimore County Department of Health, Division of Animal Control shall enforce this section.