On March 23, 2020, the U.S. Supreme Court issued its ruling in Kahler v. Kansas. To understand the importance of this case, we need to put it in historical context and examine the misunderstandings through the years of the defense of not guilty by reason of insanity.
For many years, most states embraced the so-called M’Naghten rule, which originated in 1843 in England. It said the standard for insanity would have three parts: The defendant was mentally ill; that illness resulted in an inability to know the nature and quality of his or her actions; or the illness resulted in an inability to know the wrongfulness of his or her actions.
Some states supplemented this with an “irresistible impulse test,” but it was never widely adopted because of the difficulty of measuring strength of impulse control.
In 1954, a broader test (Durham v. United States) proposed that an insanity defense was applicable if the criminal behavior was the product of a mental disease or defect.
This standard was short lived as there were many difficulties and controversies regarding the definition of mental illness and the definition of “product.”
In 1972, the courts adopted the American Law Institute Standard, which was essentially an update of M’Naghten and irresistible impulse control. The insanity defense would apply if the defendant was mentally ill and the mental illness resulted in a substantial inability to appreciate the wrongfulness of his or her actions or a substantial inability to conform his or her behavior to the requirements of the law.
This standard lasted until Congress passed the Insanity Defense Reform Act of 1984, which was essentially a return to the old M’Naghten standard. Here the impact of impulses and delusions was discarded in favor of a rigid standard that restricted insanity to someone who was severely mentally ill and therefore unable to appreciate the nature and quality or the wrongfulness of his or her behavior. Even if a person’s crime were due to a delusional system, if the defendant showed any awareness of wrongfulness, such as fleeing the scene, he or she would not meet the criteria for insanity.
Several states then abolished the insanity defense and others restricted it dramatically. Some experimented with what was called “guilty but mentally ill” in which a defendant would be convicted of a crime, but because of mental illness would be sent to a psychiatric facility until the illness was in remission. Then the defendant could transferred to prison for the remainder of the sentence.
Attorneys in several states then raised issues relevant to the restriction or elimination of the insanity standard. The Kahler case was one. Kansas had abolished the insanity defense and substituted it with a “mens rea” test. This was a narrow and strict interpretation of the first prong of M’Naghten (appreciation of the nature and quality of the act). It held that insanity could be asserted only if the defendant did not know he or she was committing an act that could be considered criminal. So, if someone thought that he or she had shot a hat rather than a person, insanity could be a defense.
The Supreme Court ruled that this restrictive insanity defense was not a violation of the 14th Amendment (due process) or equal protection under the law. The court deferred, as it had on several previous occasions, to the right of states to make laws and interpret them as they saw fit.
Essentially, the high court was saying that as long as mental health issues were considered by the state, there was no constitutional violation. The Supreme Court had ruled similarly in 2008 in Clark v. Arizona. Eric Clark contended that Arizona’s statute restricting an insanity defense to the inability to appreciate wrongfulness deprived him of the right to assert that he could not appreciate the nature and quality of his act. (Clark had shot a police officer he perceived was an alien trying to kill him.) This is, in a sense, the exact opposite of the Kahler case, illustrating that there is little consensus on these matters.
What are the implications of these narrow and restrictive laws?
Clearly, defendants who are seriously mentally ill but do not fit into the neat cubbyhole carved out by a legislature for legal insanity will not get the treatment they need.
The number of mentally ill inmates in prison has increased dramatically since the 1980s when about 4 percent were found to be mentally ill. The current figure, depending on the state, is between 18 and 25 percent.
We cannot attribute this increase solely to the tightening of the insanity defense standards. Future research should delve into this.
David Shapiro, Ph.D., is a professor of psychology at Nova Southeastern University. He has been in the field of forensic psychology for more than 50 years and has taught courses in forensic assessment, criminal law, ethics and projective techniques. He has written 12 textbooks and more than 40 peer-reviewed articles in forensic
psychology. His email address is: email@example.com.