Maryland Tax - General Section 11-220

      (a)      The sales and use tax does not apply to a sale to the State or a political subdivision of the State.

      (b)      The exemption under subsection (a) of this section may not be construed to exempt any sale of tangible personal property, otherwise taxable under this title, to a contractor to be used under a contract with the State or a political subdivision of the State for construction, repair, or alteration of real property.