The hidden effects of Montana's "abolition" of the insanity defense.

Montana abolished the affirmative insanity defense in 1979. In this article we examine the effect of this change by focusing on all defendants who raised mental health in his/her defense from 1976 to 1985. We found that while post-reform insanity acquittals did dramatically decline, there was a corresponding rise in findings of incompetent to stand trial with charges dismissed, perhaps negating the desired impact. We also compared the defendants and the legal process, finding no significant differences pre to post reform.