Missouri Revised Statutes Title XXXIV. Juries § 494.470. Challenges for cause, grounds for--juror on panel not summoned off as a witness, exception

1. No witness or person summoned as a witness in any cause, no person who has formed or expressed an opinion concerning the matter or any material fact in controversy in any case that may influence the judgment of such person, and no person who is kin to either party in a civil case or to the injured party, accused, or prosecuting or circuit attorney in a criminal case within the fourth degree of consanguinity or affinity shall be sworn as a juror in the same cause.

2. Persons whose opinions or beliefs preclude them from following the law as declared by the court in its instructions are ineligible to serve as jurors on that case.

3. All challenges for cause may be tried by the court on the oath of the person challenged or on other evidence and such challenges shall be made before the juror is sworn. If the cause of challenge be discovered after the juror is sworn and before any part of the evidence is delivered, the juror may be discharged or not in the discretion of the court.

4. A prospective juror may be challenged for cause for any reason mentioned in this section and also for any causes authorized by the law.

5. It shall be unlawful for any party to any suit to have summoned off of the regular panel of any jury, qualified for the trial of any cause, any of such jurors, to be used as witnesses in any cause pending in the court, unless the party at whose instance such juror or jurors is summoned shall first show, to the satisfaction of the court, that such juror or jurors so to be summoned are material witnesses, whose evidence he should have in the trial of the cause, and unless he so shows, the court may refuse to allow such juror to be summoned as a juror may be summoned as a witness prior to the first day of the term without first showing to the court that such person is a material witness.