Md. Code, Criminal Law § 11–104.1

(a) In Harford County and Cecil County, a person who operates a bookstore or entertainment venue in which an item or activity described in § 11-102 or § 11-103 of this subtitle is shown, displayed, or depicted and constitutes a majority of the items or activities offered for sale or rental by the bookstore or entertainment venue:

(1) shall require each individual upon entering the premises to display a driver’s license or an identification card that substantiates the individual’s age; and

(2) may not knowingly allow a minor to remain on the premises.

(b) A person who violates this section is guilty of a misdemeanor and on conviction is subject to imprisonment not exceeding 6 months or a fine not exceeding $1,000 or both.