In this section, “antique slot machine” means a slot machine that was manufactured at least 25 years before the date on which the machine is seized. A person may not be convicted under § 12-302 of this subtitle if the person shows by a preponderance of the evidence that the slot machine: is an antique slot machine; and was not operated for gambling purposes while in the person’s possession. If the defense is offered that a seized slot machine is an antique slot machine, the slot machine may not be destroyed or otherwise altered until after a final judicial determination, including review on appeal, that the defense does not apply. If the defense applies, the person who seized the slot machine shall return the slot machine in accordance with applicable provisions of law for the return of property.