People v. Moore.
2021 CO 26. No. 20SA293. Not Guilty by Reason of Insanity Plea—Expert Mental Condition Evidence—Self-Defense.
May 4, 2021
In this opinion, the Supreme Court held that, absent an insanity plea, the trial court must exclude any evidence that is probative of insanity, as that term has been defined by the legislature, irrespective of the ostensible purpose for which it is offered. The court must therefore exclude parts of the proposed testimony that tend to prove that defendant (1) was so diseased or defective in mind at the time of the commission of the act as to be incapable of distinguishing right from wrong, or (2) suffered from a condition of mind caused by mental disease or defect that prevented defendant from forming a culpable mental state that is an essential element of a crime charged. For a defendant’s mental condition to implicate the statutory definition of “mental disease or defect” at the time of the offense, it must have been so severely abnormal that it grossly and demonstrably impaired his or her perception or understanding of reality, without being attributable to the voluntary ingestion of drugs or alcohol. The court must parse any proffered mental condition evidence to distinguish what is probative of insanity under this exacting definition from what is not.
Accordingly, the district court’s order allowing the blanket admission of mental condition evidence was vacated.