Md. Code, Transportation § 18–105

(a) A person may not rent a motor vehicle to any other person if he knows that the other person is under the influence of alcohol, impaired by alcohol, impaired by a drug, a combination of drugs, or a combination of one or more drugs and alcohol, or impaired by a controlled dangerous substance.

(b) A person may not rent a motor vehicle to any other person if the person knows that an individual who will drive the rented vehicle is under the influence of alcohol, impaired by alcohol, impaired by a drug, a combination of drugs, or a combination of one or more drugs and alcohol, or impaired by a controlled dangerous substance.