Mo. Rev. Stat. § 525.150
Except as herein provided, no garnishment shall be issued by any court in any cause where the sum demanded is two hundred dollars or less, and where the property sought to be reached is wages due the defendant by any railroad corporation, until after judgment shall have been recovered by the plaintiff against the defendant in the action; provided, this section shall not apply when the debt or claim sued for was contracted or accrued in this state; provided further, in such cases the petition or statement filed in the cause and the writ or summons of garnishment shall affirmatively show that the debt or claim sued for was contracted or accrued in this state and is owing to a bona fide citizen or resident of this state.
§ 525.150, RSMo
RSMo 1939 § 1574