Whenever the owner or operator of a mercantile establishment or any agent or employee of the owner or operator detains, arrests, or causes to be detained or arrested any person reasonably thought to be engaged in shoplifting and, as a result of the detention or arrest, the person so detained or arrested brings an action for false arrest or false imprisonment against the owner, operator, agent, or employee, no recovery shall be had by the plaintiff in such action where it is established by competent evidence:

(1) That the plaintiff had so conducted himself or behaved in such manner as to cause a man of reasonable prudence to believe that the plaintiff, at or immediately prior to the time of the detention or arrest, was committing the offense of shoplifting, as defined by Code Section 16-8-14; or

(2) That the manner of the detention or arrest and the length of time during which such plaintiff was detained was under all the circumstances reasonable.