507.090. Intervention--when as of right and when permissive--procedure.
Intervention--when as of right and when permissive--procedure.
507.090. 1. Upon timely application anyone shall be permitted tointervene in an action
(1) When a statute confers an unconditional right to intervene; or
(2) When the representation of the applicant's interest by existingparties is or may be inadequate and the applicant is or may be bound by ajudgment in the action; or
(3) When the applicant is so situated as to be adversely affected by adistribution or other disposition of property in the custody of the court orof an officer thereof.
2. Upon timely application anyone may be permitted to intervene in anaction
(1) When a statute confers a conditional right to intervene; or
(2) When an applicant's claim or defense and the main action have aquestion of law or fact in common. In exercising its discretion the court shall consider whether theintervention will unduly delay or prejudice the adjudication of the rights ofthe original parties.
3. (1) A person desiring to intervene shall serve a motion to interveneupon all parties affected thereby. The motion shall state the groundstherefor, and shall be accompanied by a pleading setting forth the claim ordefense for which intervention is sought. The same procedure shall befollowed when a statute of this state gives a right to intervene.
(2) When the validity of a statute, regulation or constitutionalprovision of this state, or an ordinance or regulation of a governmentalsubdivision thereof affecting the public interest is drawn in question in anyaction to which the state or governmental subdivision or an officer, agency oremployee thereof is not a party, the court may in its discretion notify thechief legal officer of the state or subdivision thereof affected.
(3) In all cases and proceedings wherein the validity of a statute,regulation or constitutional provision of this state affecting the publicinterest is drawn in question, and the state or an officer, agency or employeethereof is not a party, the state of Missouri may in the discretion of thecourt be permitted to intervene, upon proper application.
(4) In all cases and proceedings wherein the validity of an ordinance orregulation of any governmental subdivision of this state affecting the publicinterest is drawn in question, and the governmental subdivision, or anofficer, agency or employee thereof is not a party, the governmentalsubdivision may in the discretion of the court be permitted to intervene, uponproper application.
(L. 1943 p. 353 § 21)(1980) Foster parents who have had child in physical custody for extended period of years did not have requisite interest to intervene as a matter of right in proceeding by natural mother to regain custody of her children. In re Matter of Trapp (Mo.), 595 S.W.2d 193.