Md. Code, Labor and Employment § 8–105

Unless a report or other written or oral communication that is made or delivered in connection with this title is false and malicious, a person may not bring an action for abusive or wrongful discharge, libel, or slander based on the report or communication from:

(1) an employee to an employer;

(2) an employer to an employee; or

(3) an employee or an employer to the Secretary or Board of Appeals or any agent, employee, or representative of the Secretary or Board of Appeals.