Md. Code, Local Government § 9–205

(a) (1) The voters of a charter county may reserve in the charter the

power of referendum by which they may submit a local law enacted by the county

council, by petition, to the voters for approval or rejection.

(2) The charter shall specify:

(i) what types of local laws may be petitioned to referendum;

and

(ii) whether a part of a local law may be petitioned to

referendum.

(b) (1) Subject to paragraph (2) of this subsection, in implementing

procedures that relate to the power of referendum, the charter or the local laws shall

provide adequate details as to time, notice, and form.

(2) The initial notice of a referendum vote shall be given at least 30

days before the election.