February 25, 2020

Kahler v. Kansas


Do the Eighth and Fourteenth Amendments Permit a State to Abolish the Insanity Defense?


This case examines the constitutionality of a Kansas statute that has replaced the insanity defense with a mens rea test. Specifically, it explores whether abolishing the insanity defense violates the Eighth Amendment and/or Fourteenth Amendment.

Docket No. 18-6135
Argument Date: October 7, 2019
From: Kansas Supreme Court
by William W. Berry III
University of Mississippi School of Law, University, MS


Do the Eighth and Fourteenth Amendments permit a state to abolish the insanity defense?


In 2008, James Kraig Kahler, his wife, and three children resided in Weatherford, Texas. That summer, Kahler took a new job as the director of water and light for the city of Columbia, Missouri. Around the same time, Kahler’s wife Karen indicated interest in experimenting by engaging in a sexual relationship with a female trainer with whom she worked. Kahler assented to the relationship.

Kahler thought the affair would end when Karen and the kids moved to Columbia later that year. The affair, however, continued and led to a verbal altercation at a New Year’s party and a shoving match between Kahler and his wife. The relationship disintegrated from there with Karen filing for divorce in mid-January 2009. In mid-March, Kahler was arrested at a city council meeting pursuant to a battery complaint filed by Karen. Karen then took the children and moved out of the house.

Kahler spiraled downward after this sequence of events, becoming increasingly preoccupied with his personal problems. His job performance suffered, and he was fired in August 2009. Kahler’s parents were quite concerned; they moved him from Columbia back to their ranch in Meriden, Kansas.

Kahler’s son Sean spent the Thanksgiving holiday with him. Sean called his mother to request to stay longer with his father. Karen declined and Karen’s mother came to pick up Sean while Kahler was running an errand.

Later that day, Kahler drove to the home of Karen’s parents, an hour away. He entered the house with a high-powered rifle and shot Karen twice, but did not harm Sean. Kahler then walked through the house, shooting and ultimately killing both of his teenage daughters and his mother-in-law.

At trial, the defense did not dispute that Kahler had shot and killed the victims. Instead, the defense argued that Kahler’s severe depression had rendered him incapable of forming the intent and premeditation required to establish the crime of capital murder. The jury convicted Kahler of capital murder. In the penalty phase, the same jury recommended a death sentence.

On appeal, Kahler raised a number of issues to the Kansas Supreme Court, including arguing that Kansas’s mens rea approach to the insanity defense violates the Due Process Clause of the Fourteenth Amendment. The parties dispute whether Kahler also raised a similar challenge under the Eighth Amendment.

The Kansas Supreme Court affirmed Kahler’s convictions. The Court rejected Kahler’s constitutional challenge because it had considered and rejected the same arguments in State v. Bethel, 66 P.3d 840 (Kan. 2003). Bethel had upheld the mens rea approach of the Kansas capital statute against a due process challenge, finding that an affirmative insanity defense was not a constitutionally required fundamental right. The same case also rejected an Eighth Amendment challenge, finding that Kansas law “does not expressly or effectively make mental disease a criminal offense.”

Kahler subsequently filed a petition for certiorari, which the Supreme Court granted on March 18, 2019.


Prior to the adoption of the Kansas statute at issue, KSA 22-3220, Kansas followed the widely adopted M’Naghten test for insanity. The M’Naghten rule provides that a defendant is not criminally responsible when (1) the defendant does not know the nature or quality of his act, or alternatively, (2) does not know right from wrong with respect to the act. M’Naghten’s Case, 8 Eng. Rep. 718 (1843); State v. Baker, 819 P.2d 1173 (1991). With respect to the second prong, the defendant must prove that he did not know what he was doing was contrary to law at the time of the criminal act.

The new Kansas statute, effective January 1, 1996, abandoned the M’Naghten test in favor of the “mens rea approach.” This statute eliminated insanity as an affirmative defense, instead moving evidence of mental disease or defect into the consideration of mens rea—the intent required to find the defendant guilty of the crime. In other words, under the Kansas statute a defendant suffering from mental disease or defect can argue that the disease or defect prevented him from forming the mental intent needed to commit the crime, but cannot use the inability to distinguish right from wrong as the basis for an affirmative defense to a criminal act.

The first question before the Supreme Court is whether the abolition of the insanity defense, as done under the Kansas statute, violates the Due Process Clause of the Fourteenth Amendment. The Fourteenth Amendment’s Due Process Clause protects those “principle[s] of justice so rooted in the traditions and conscience of our people as to be ranked as fundamental.” Patterson v. New York, 432 U.S. 197 (1977). On the one hand, the Court has recognized that it “should not lightly construe the Constitution so as to intrude upon the administration of justice by the individual States,” who have traditionally been responsible for defining the scope of criminal liability. Patterson v. New York, 432 U.S. 196 (1977). On the other hand, the purpose of the Bill of Rights includes protecting “the fragile values of a vulnerable citizenry from the overbearing concern for efficiency and efficacy” that often influences legislatures, whether the values are “deeply rooted” rights or those “implicit in the concept of ordered liberty.” Washington v. Glucksberg, 521 U.S. 702 (1997). The Court’s “primary guide in determining whether the principle in question is fundamental is, of course, historical practice.” Montana v. Egelhoff, 518 U.S. 37 (1996).

Kahler argues that the insanity defense fits the definition of a fundamental right. Specifically, Kahler asserts that the Due Process Clause requires some mechanism to excuse a non-culpable mentally ill defendant from criminal liability. The petitioner traces the long history of the insanity defense from ancient civilizations to its modern usage. This includes its use in the United States “from the Founding to the present.” Kahler subsequently emphasizes the continuation of the insanity defense in modern American criminal law, with 45 states still using it, and as recently as 1979, every American jurisdiction recognizing the defense.

The central thrust of Kahler’s Fourteenth Amendment claim, then, is that the insanity defense has historically been a fundamental right and remains deeply rooted. As explained by the Mississippi Supreme Court in Sinclair v. State, 132 So. 581 (Miss. 1931),

So closely has the idea of insanity as a defense been woven into the criminal jurisprudence of English speaking countries that it has become a part of the fundamental laws thereof, to the extent that a statute which attempts to deprive a defendant of the right to plead it will be unconstitutional and void.

By contrast, Kansas argues that the Fourteenth Amendment does not require an insanity defense, and the mens rea approach satisfies the requirements of due process. With respect to the history of the insanity defense, Kansas suggests that there is not one historical insanity defense, as posited by Kahler, but instead a wide range of different conclusions concerning the concept of insanity. Kansas argues that the different competing tests adopted by different jurisdictions throughout history, of which the “mens rea approach” is but one, means that there has never been a consensus concerning the doctrinal approach to insanity, or at least one that rises to the level of a fundamental right under the Fourteenth Amendment.

Even if the Court decides that an insanity defense is a fundamental right, it still must assess whether the mens rea approach satisfies that right. Kahler claims that the Kansas approach falls far short of what the Constitution requires. According to Kahler, the effect of channeling the insanity defense into the mens rea element of the crime will be neglecting the rights of some insane defendants who lack moral culpability. Kahler emphasizes that while in some cases there may be overlap, the insanity defense is broader than the mens rea approach. This means that individuals excused by the insanity defense are often not excused by the mens rea approach.

Kansas argues that the Due Process Clause does not mandate a particular insanity test. Kansas reasons that the current state of scientific knowledge is inadequate to conclusively point to a particular test, and as such, states have the prerogative to choose which of the insanity tests best fits their doctrinal vision. The central point Kansas makes here relates to the competing approaches to this question among the various states. Because there are a number of different state treatments of insane defendants under state criminal law, Kansas claims that the Due Process Clause does not mandate a particular one.

Along the same lines, Kansas believes that it is free to address the question of insanity as it sees fit, as long as its approach is rational. To that end, Kansas explains that its mens rea approach is constitutional because it has reasonably determined that individuals who voluntarily and intentionally commit a crime are blameworthy even if they do not know their actions are wrong.

The second issue before the Court is whether the Kansas statutory scheme violates the Eighth Amendment. Kahler argues that the Kansas approach is cruel and unusual in that it abolishes the insanity defense. Kahler believes that the statute violates the Eighth Amendment both as a matter of an originalist interpretation of the Eighth Amendment and as a matter of the Court’s modern Eighth Amendment proportionality cases.

Kahler begins by claiming that criminally punishing the insane would have been cruel and unusual at the founding of our country. To support this claim, Kahler cites to the common law, which supports a M’Naghten-type limitation on punishing those incapable of separating right from wrong. In particular, Kahler points to the tradition of allowing families to address the problems of criminal behavior by the insane, rather than putting such individuals in the criminal justice system.

Further, Kahler asserts that criminally punishing the insane is grossly disproportionate and serves no legitimate purpose. To support this inquiry, Kahler applies the Court’s evolving standards of decency test in concluding that abolition of the insanity defense violates the Eighth Amendment. The first part of the test, the objective indicia, would examine the practices among the states to determine whether a particular approach was “unusual.” As Kahler points out, almost every jurisdiction—48 jurisdictions—uses some kind of insanity defense. The second part of the test, the subjective indicia, examines whether one or more purposes of punishment can justify the sentence. If not, the punishment is disproportionate and “cruel.” Here, Kahler argues that insane offenders lack the culpability to receive the punishments accorded to sane criminal defendants. Specifically, Kahler claims that none of the four purposes of punishment—retribution, deterrence, incapacitation, or rehabilitation—support the punishment of people who cannot rationally appreciate the difference between right and wrong.

In addition to arguing that Kahler waived his Eighth Amendment argument and that the Court should not reach the merits of that question, Kansas takes issue with Kahler’s claim that punishing the insane is cruel and unusual. In particular, Kansas argues that convicting those who voluntarily and intentionally kill others is not cruel and unusual, even if the offender does not recognize that his actions are wrong.

Kansas next asserts that the Eighth Amendment applies only to punishments themselves, not criminal defenses. The distinction highlighted here is between the conviction and the sentence. Kansas argues that the Eighth Amendment only applies to the latter, but that Kahler is only challenging the former.

Kansas also contradicts Kahler’s view of the founding as dispositively establishing punishment for insane individuals, suggesting this approach did not arrive fully until the M’Naghten decision in the nineteenth century. Likewise, Kansas maintains that the mens rea approach satisfies all four purposes of punishment. Again, it focuses on the idea that voluntary and intentional killings are culpable and those who commit them deserve punishment, irrespective of the offender’s appreciation of the wrongfulness.

Finally, Kansas concludes by making a harmless error argument with respect to Kahler. Even if a right-and-wrong test was constitutionally required, Kansas contends that Kahler is not insane, and as such different jury instructions would have led to the same outcome in the case.


For Kahler, the case is significant in opening the door to a new trial and an opportunity to undermine his criminal conviction, albeit with the consequence of institutionalization.

More broadly, this case will have much to say about the scope of the Due Process Clause, and to a lesser degree, the Eighth Amendment, as well as the nature of criminal law more generally. With respect to due process, this case will add another chapter to the delineation of due process rights, and the connection between historical practice and fundamental rights. Interestingly, the competing views here raise the question of how specific a right must be to become fundamental. Kahler claims that the presence of the concept of insanity is enough to render it fundamental; Kansas contends the lack of a unified, consistent approach means that the right is not fundamental.

With the Eighth Amendment, the significance relates to the possible expansion of doctrine in applying it to criminal defenses, not just criminal punishments. Again, the parties highlight potential differences, but these may be no more than semantics. Kahler believes that Eighth Amendment protection is needed here as a defense against cruel and unusual punishments, with the absence of an insanity defense making such unconstitutional punishments possible. Kansas, on the other hand, supports the idea that the insanity defense only addresses the question of criminal conviction and does not speak to the extent of punishment, placing it outside the scope of the Eighth Amendment.

Beyond the scope of the Constitution, this case poses the question of how states should understand criminal liability and punishment more generally. Should guilt and culpability focus solely on the intent to commit the act? Or should guilt and culpability encompass one’s moral awareness and competency, including the ability to separate right from wrong? To be sure, this case has the potential to make broad statements concerning the future application of criminal law to insane individuals.

In the final analysis, the Court will have to decide whether the insanity defense is constitutionally required or can be statutorily replaced by Kansas’ mens rea approach.

There are a number of amicus briefs for both parties. On behalf of Kahler, there are briefs filed by a group of philosophy professors, a group of 290 criminal law and mental health law professors, the American Bar Association, the ACLU, the National Association of Criminal Defense Lawyers, the Idaho Association of Criminal Defense Lawyers, the American Psychiatric Association, and a group of legal historians and sociologists.

On behalf of Kansas, there are briefs filed by the United States, Lynn Denton (Karen Kahler's sister) along with victims groups from Arizona and Utah, and 16 states, led by Utah.

Finally, Professor John Stinneford has written a neutral amicus brief concerning the history and original meaning of the Eighth Amendment.

William W. Berry III is an associate professor of law and Montague Professor at the University of Mississippi School of Law. He can be reached at wwberry@olemiss.edu and 662.915.6859.

PREVIEW of United States Supreme Court Cases 47, no. 1 (October 7, 2019): 4–7. © 2019 American Bar Association

PREVIEW of United States Supreme Court Cases 47, no. 4 (January 13, 2020): 4–6. © 2020 American Bar Association


  • For Petitioner Lucky Brand Dungarees, Inc., et al. (Dale M. Cendali, 212.446.4800)
  • For Respondent Marcel Fashions Group, Inc. (Michael B. Kimberly, 202.756.8901)


In Support of Petitioner James Kraig Kahler

  • 290 Criminal Law and Mental Health Law Professors (Richard Jeffrey Bonnie, 434.924.3209)
  • American Bar Association (Robert M. Carlson, 312.988.5000)
  • American Civil Liberties Union and the ACLU Foundation of Kansas (Caitlin Joan Halligan, 212.390.9000)
  • American Psychiatic Association, et al. (Aaron M. Panner, 202.326.7900)
  • Idaho Association of Criminal Defense Lawyers, et al. (Jonah Joshua Horwitz, 208.331.5530)
  • Legal Historians and Sociologists (Allison R. McLaughlin, 303.244.1800)
  • National Association of Criminal Defense Lawyers (Jonathan L. Marcus, 202.371.7000)
  • Philosophy Professors (Eugene R. Fidell, 202.256.8675)

In Support of Respondent Kansas

  • Lynn Denton, Arizona Voice for Crime Victims, Inc., and Utah Crime Victims Legal Clinic (Allyson Ho, 214.698.3233)
  • United States (Noel J. Francisco, Solicitor General, 202.514.2217)
  • Utah (Tyler Green, 801.538.9600)

In Support of Neither Party

  • John F. Stinneford (Andrew Timothy Tutt, 919.699.5905)