Mo. Rev. Stat. § 540.190
Current with changes from the 2023 Legislative Session
If any witness, appearing before a grand jury, refuses to testify or to answer any interrogatories in the course of his examination, the fact and the question refused shall be communicated to the court in writing. The court shall thereupon determine whether the witness is bound to answer or not, and the grand jury shall be immediately informed of the decision.
§ 540.190, RSMo
RSMo 1939 § 3916, A.L. 1989 S.B. 127, et al.