Mo. Rev. Stat. § 86.1160

Whenever a member's service is terminated for any reason prior to death or retirement and such member has less than fifteen years of creditable service, or a member's service is terminated after conviction of a felony, or a member's service is terminated for any reason and such member requests the withdrawal of all such member's accumulated contributions to the retirement system, such member shall be paid the amount of such member's accumulated contributions in one lump sum, without interest, and such payment shall be in lieu of any and all other benefits to which such member or any beneficiary or survivor thereof might otherwise be or become entitled under sections 86.900 to 86.1280.