For purpose of this chapter, "merchant police" means any person engaged in the business of watching, guarding or protecting any premises, property or persons. The term does not include any individual who has only one employer and who is employed to watch, guard or protect only the premises, property or person of that employer, any common carrier engaged in interstate commerce, or any individual employed by the carrier to watch, guard or protect premises, property or persons for such carriers.
(Code 2000 § 9.305)