Md. Const. art. XI-A, § 6

The power heretofore conferred upon the General Assembly to prescribe the number, compensation, powers and duties of the County Commissioners in each County, and the power to make changes in Sections 1 to 6 inclusive, Article XI of this Constitution, when expressly granted as hereinbefore provided, are hereby transferred to the voters of each County and the voters of City of Baltimore, respectively, provided that said powers so transferred shall be exercised only by the adoption or amendment of a charter as hereinbefore provided; and provided further that this Article shall not be construed to authorize the exercise of any powers in excess of those conferred by the Legislature upon said Counties or City as this Article sets forth.