The "clear and convincing evidence" standard requires that decisions to forego, i.e., withdraw or withhold, life-sustaining treatment for incompetent patients are based on a significant level of evidence that clearly illustrates a prior and consistent decision on the part of the patient to refuse treatment under circumstances highly similar to the current situation for which a
surrogate decision is required. Clear and convincing evidence of the person’s actual wishes is the highest standard of evidence that may be required in
substituted judgments. The clear and convincing evidence standard is used in civil cases (including some health law cases) and is less stringent than the "beyond the reasonable doubt" standard used in criminal law. It is up to individual states to decide whether or not to require clear and convincing evidence in proceedings where a guardian seeks to discontinue life-sustaining treatment for a permanently unconscious or otherwise incompetent person. Furthermore, some courts may vary in their definition of clear and convincing evidence, that is, some definitions may be more stringent than others. Depending on how a court defines clear and convincing evidence, this requirement may make this form of surrogate decision-making not so much a
substituted judgment, but more the enactment of an
advance directive or the exercise of the formerly competent person’s
own judgment. Currently, Missouri, Michigan, and New York are the only states that require clear and convincing evidence in such cases. (See the cases of
Cruzan, Nancy and
Martin, Michael.)
