Maryland Governor - Executive and Administrative Departments Section 14-809

      Bonds issued under this subtitle, their transfer, the interest payable on them and any income derived from them, including any profit realized in their sale and exchange, shall be exempt at all times from every kind and nature of taxation by this State or by any of its political subdivisions, municipal corporations, or public agencies of any kind. Nothing in this subtitle shall prevent any local governing body from authorizing the issuance and sale of bonds the interest on which is not excludable from gross income for federal income tax purposes.