Md. Code, Public Utilities § 10-103

(a) Except as provided in subsections (b) and (c) of this section, a person may not operate a motor vehicle for hire in the State under a permit or authorization to transport passengers issued by the Commission or the appropriate local authority unless the person holds a for–hire driver’s license or a transportation network operator’s license issued by the Commission.

(b) (1) A county or municipal corporation may license taxicab drivers who drive taxicabs that are based in that county or municipal corporation if, at a minimum, the county or municipal corporation conducts a criminal record check and driving record check of each applicant for a license.

(2) A taxicab driver licensed by a county or municipal corporation is not required to be licensed by the Commission.

(c) (1) (i) In this subsection the following words have the meanings indicated.

(ii) “Washington Metropolitan Area Transit District” means the transit district created under § 10–204 of the Transportation Article and includes, for the State, Montgomery and Prince George’s counties and the political subdivisions located within those counties.

(iii) “WMATC” means the Washington Metropolitan Area Transit Commission created under § 10–204 of the Transportation Article.

(2) A person providing transportation network services in the portion of the Washington Metropolitan Area Transit District located within the State must hold a transportation network operator’s license issued by the Commission unless the person is providing a trip for which WMATC requires a certificate of authority.