Insanity Defense Reform Act 1984
Definition
US federal legislation passed after the Hinckley acquittal that restricted expert psychiatric and psychological testimony in insanity proceedings by prohibiting direct ultimate-issue opinion on the defendant's mental state for the offence charged.
- Jurisdiction
- United States, federal
- Enacted
- 1984
- Trigger
- Acquittal of John Hinckley Jr.
- Restricts
- Direct ultimate-issue opinion testimony
Common questions
What is the practical effect of the ultimate-issue restriction on an expert's testimony?+
An expert can describe a defendant's diagnosed condition and its features but is barred from stating directly whether the defendant was legally insane at the time of the offence, since that final determination is reserved for the jury.
Why did the Hinckley verdict prompt this specific restriction rather than a broader change?+
Public reaction focused on the perception that expert psychiatric testimony had effectively decided the case's outcome, so Congress narrowed what experts could assert about the ultimate legal question while leaving clinical testimony about symptoms and diagnosis intact.
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- Ultimate-Issue Rule
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