The thing is, I am not sure that the jury will receive instruction specifically on what constitutes insanity. It becomes a version of the "reasonable person" rubric, in which the jury itself decides whether the person was insane. Hallucinations are one way of showing that, but perhaps not the only way?
The DA did explain it a bit today, and below is the insanity section from the
Colorado standard jury instructions. Even if anybody is convinced she has multiple personalities, I don't think even that qualifies as a condition that "grossly and demonstrably impairs a person’s perception or understanding of reality."
I:01 AFFIRMATIVE DEFENSE OF INSANITY
The evidence in this case has raised the defense of insanity, as a defense to the crime of [insert name of offense(s) here].
The defendant was insane at the time of the commission of the act if:
1. he [she] 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 with respect to that act; or
2. he [she] suffered from a condition of mind caused by a mental disease or defect that prevented him [her] from forming a culpable mental state that is an essential element of a crime charged.
But care should be taken not to confuse mental disease or defect with moral obliquity, mental depravity, or passion growing out of anger, revenge, hatred, or other motives and kindred evil conditions because, when an act is induced by any of these causes, the person is accountable to the law.
In addition, “diseased or defective in mind” does not refer to an abnormality manifested only by repeated criminal or otherwise antisocial conduct. + Evidence of knowledge or awareness of the victim’s actual or perceived gender, gender identity, gender expression, or sexual orientation shall not constitute inability to distinguish right from wrong.
Similarly, “mental disease or defect” means only those severely abnormal mental conditions that grossly and demonstrably impair a person’s perception or understanding of reality and that are not attributable to the voluntary ingestion of alcohol or any other psychoactive substance. “Mental disease or defect” does not include an abnormality manifested only by repeated criminal or otherwise antisocial conduct.
The prosecution has the burden to prove beyond a reasonable doubt that the defendant was not insane at the time of the commission of the act. In order to meet this burden of proof, the prosecution must disprove, beyond a reasonable doubt, both of the above numbered conditions.
After considering all the evidence, if you decide the prosecution has failed to meet this burden of proof, then the prosecution has failed to prove that the defendant was sane at the time of the commission of the act, which is an essential element of [insert name(s) of offense(s)]. In that event, you must find the defendant not guilty and have the foreperson sign the designated section of Part A of the verdict form to indicate your verdict.
After considering all the evidence, if you decide the prosecution has met this burden of proof, then the prosecution has proved that the defendant was not insane at the time of the commission of the act. In that event, your verdict concerning the charge of [insert name(s) of offense(s)] must depend upon your determination whether the prosecution has met its burden of proof with respect to the remaining elements of [that] [those] offense.