October Term 2005 · Docket 05-5966

Can states limit insanity defense evidence?

Eric Clark argues Arizona barred relevant mental state evidence. The state claims it controls the insanity defense definition.

Official caption
Clark v. Arizona
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Argued
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Official Transcript

Verified source milestones

  1. — An official oral-argument transcript was verified.

The arguments, in order

This case may have been argued more than once. Each entry below uses that session's official transcript. Later arguments do not erase earlier ones.

  1. Argument 1 ·

    What happened at the argument

    David Goldberg argued Clark lost his fair trial right. He stated Arizona law required proof of intent.

    General Clement argued Arizona's law is constitutional. He stated the state controls the defense definition.

    Justice Kennedy asked if the state deemed testimony irrelevant. He sought clarification on the state's position.

    Read the official transcript for this argument · Official argument details

    Sources used for this argument breakdown

A citizen's guide to the whole case

What this case is about

This case tests state power to define insanity. It also tests limits on mental state evidence.

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How the case got here

The Supreme Court heard oral argument in this case on April 19, 2006.

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What each side wants

Clark wants the Court to strike down Arizona's insanity law. He seeks to admit his mental state evidence.

Arizona wants the Court to uphold its insanity law. It seeks to keep mental state evidence excluded.

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What each side says

Clark argues Arizona violated his Fourteenth Amendment rights. He claims the state barred relevant evidence.

Arizona argues it has discretion to define the insanity defense. It claims the Constitution allows this choice.

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What the justices asked

Justice Ginsburg asked about the name guilty except insane. She questioned what specific crime Clark committed.

Justice Breyer asked if Clark knew right from wrong. He questioned the cognitive element of the defense.

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Why it matters

This case defines state control over criminal defenses. It shapes how courts handle mental illness evidence. It impacts future insanity defense trials nationwide.

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What happens next

This article currently covers the argument record. Use the official docket link for later case activity.

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Official Court provenance

Official docket and case history · Official Supreme Court oral-argument detail page

Title and summary sources

Revision history

  1. Revision 1 · Official Transcript ·

    Correction: Rewritten to the concise citizen-facing editorial standard.

  2. Revision 2 · Official Transcript ·

    Correction: Migrated to the dated official Court activity contract without model use.

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