Maryland Code, Courts and Judicial Proceedings § 9-115

Where character evidence is otherwise relevant to the proceeding, no person offered as a character witness who has an adequate basis for forming an opinion as to another person's character shall hereafter be excluded from giving evidence based on personal opinion to prove character, either in person or by deposition, in any suit, action or proceeding, civil or criminal, in any court or before any judge, or jury of the State.