Mo. Rev. Stat. § 58.449
The contents of the report and results of any test made pursuant to the requirements or authorizations of sections 58.445 to 58.449 shall be used primarily for statistical purposes which do not reveal the identity of the deceased and shall not be public information. The contents of the report and the results of any test so made shall be released upon request to any person involved in the accident, spouse of or any family member related within the second degree of consanguinity to a person killed in the accident, attorney for a person involved in the accident, or insurer of a person involved in the accident or whose property is involved in an accident for purposes of investigation of any civil claim or defense. This information shall be released to other parties only upon the issuance of a subpoena duces tecum by a court of competent jurisdiction for use in any civil or criminal action arising out of the accident.
§ 58.449, RSMo