Maryland Code, Election Law § 16-304

(1) permit a ballot or ballots to be placed into a ballot receptacle prior to the time for voting; or

(2) place a ballot in a ballot receptacle unless the ballot is offered by a properly registered voter or is a provisional ballot placed with other provisional ballots of the same character.

(1) cause or permit a ballot, including a provisional ballot, to be cast or deposited in a ballot receptacle, voting device, or other receptacle designed for the collection of ballots other than by a person entitled under this article to cast a ballot; or

(2) substitute, alter, add, or remove a submitted ballot from a ballot receptacle, voting device, or other receptacle designed for the collection of ballots, except when instructed to do so by the election director.