Supreme Court Rules States Can Bar Insanity Defense

WASHINGTON – The Supreme Court ruled Monday that states can prevent criminal defendants from pleading insanity without violating their constitutional rights.

The justices’ 6-3 decision came in the case Kahler v. Kansas.

As recounted in the decision, James Kraig Kahler was sentenced to death for killing his estranged wife, two teenage daughters and his wife’s grandmother.

Kahler wanted to mount an insanity defense, but Kansas is one of four states that eliminated a defendant’s ability to plead not guilty by reason of insanity.

Idaho, Montana and Utah are the others. Alaska also places limits on when the insanity defense may be used.

A majority of the justices found that due process does not require a state to adopt an insanity test that turns on a defendant’s ability to recognize his crime was morally wrong.

The decision is likely to encourage states across the country to toughen standards for defendants who wish to plead not guilty by reason of insanity.

Writing for the majority, Justice Elena Kagan concluded, “Kansas takes account of mental health at both trial and sentencing. It has just not adopted the particular insanity defense Kahler would like. That choice is for Kansas to make — and, if it wishes, to remake and remake again as the future unfolds.”

She was joined in the majority by Chief Justice John Roberts, and Justices Clarence Thomas, Samuel Alito, Neil Gorsuch and Brett Kavanaugh.

Justice Stephen Breyer filed a dissenting opinion, in which he was joined by Justices Ruth Bader Ginsburg and Sonia Sotomayor.

In it, Breyer argued that Kansas “has eliminated the core of a defense that has existed for centuries: that the defendant, due to mental illness, lacked the mental capacity necessary for his conduct to be considered morally blameworthy.”