Maryland Code, Business Regulation § 16-215

(1) examine the package to find out whether tobacco tax stamps are affixed properly to the package as required by § 12-304 of the Tax-General Article; and

(2) reject any unstamped or improperly stamped cigarettes by:

(c)(1) There is a presumption that any unstamped cigarettes in the possession of a retailer, subwholesaler, vending machine operator, or wholesaler are held in violation of this subtitle.

(2) A retailer, subwholesaler, vending machine operator, or wholesaler who holds unstamped cigarettes has the burden to prove that the cigarettes are not held in violation of this subtitle.