Mo. Rev. Stat. § 301.302: Missing license plate tab, no citation issued, when.

A citation shall not be issued to any person stopped by law enforcement for a missing license plate tab or tabs if such person indicates that the tab or tabs have been stolen and a check on such person's vehicle registration reveals that the vehicle is properly registered. A law enforcement officer may issue a warning under these circumstances. In the event a citation is improperly issued to a person for missing tabs when the requirements of this section are met, any court costs shall be waived.