Missouri Revised Statutes Title XXVIII. Contracts and Contractual Relations § 431.064. Experimental treatment, tests, and drugs, consent to administer by third party--life-threatening emergencies, consent by whom

1. When an adult person, because of a medical condition, is treated by a teaching hospital for a medical school accredited by the American Osteopathic Association or the American Medical Association and such person is incapable of giving informed consent for an experimental treatment, test or drug, then such treatment, test or drug may proceed upon obtaining consent of a legal guardian, attorney-in-fact, or a family member in the following order of priority:

2. Nothing in this section shall authorize such legal guardian, attorney-in-fact, or family member to consent to treatment in contravention to such incapacitated person's expressed permission regarding such treatment.

3. In a life-threatening emergency, consent of such an incapacitated person to any research program or experimental procedure shall not be required when the institutional review board responsible for the review, approval, and continuing review of the research activity has approved both the research activity and a waiver of informed consent and has both found and documented that the requirements for an exception from informed consent requirements for emergency research, as provided under Part 50 of Title 21 or Part 46 of Title 45 of the Code of Federal Regulations, as amended, have been satisfied.