October Term 2019 · Docket 18-6135

Does the Constitution require states to allow a moral capacity insanity defense?

Kansas rejects the moral capacity insanity defense. the side that brought the case argues this violates due process.

Official caption
Kahler v. Kansas
Latest argument session
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Argued
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Official Transcript

Verified source milestones

  1. — An official oral-argument transcript was verified.
  2. — 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

    Sarah Schrup argued moral capacity defines criminal culpability.

    She stated this understanding persists in most jurisdictions.

    Elizabeth Prelogar argued the side that brought the case failed to prove a constitutional violation.

    She stated the state legislature made a valid policy choice.

    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

Kansas law requires defendants to know an act is illegal to claim insanity. It does not require proof that the defendant understood the act was morally wrong. the side that brought the case argues this standard violates the Constitution. The state argues it has the right to define criminal culpability.

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How the case got here

The Supreme Court heard oral argument in this case on October 7, 2019.

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What each side wants

the side that brought the case wants the Court to strike down the Kansas insanity standard.

Kansas wants the Court to uphold its current insanity law.

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What each side says

the side that brought the case argues moral capacity is a fundamental right protected by due process.

Kansas argues states may define insanity without a moral capacity requirement.

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What the justices asked

Justice Alito asked if knowing an act is illegal suffices for sanity.

Justice Alito asked if a mental disorder diagnosis alone proves insanity.

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Why it matters

This case defines the constitutional limits on state insanity defenses. It determines whether moral judgment is a required element of criminal responsibility. The outcome shapes how states evaluate defendant culpability in criminal trials.

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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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