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The Insanity Defense at the Supreme Court

Is rejecting the insanity defense sane?

The insanity defense is going to the Supreme Court.

First Monday in October—the traditional opening of the Supreme Court term—is coming up and the first case the Court will hear is a challenge to the legitimacy of the insanity defense.

The state legislature of Kansas decided that the insanity defense is not real. It is eyewash, b.s., a trick. Most states disagree, accepting the more common view that the insanity defense is legitimate. (Though Alaska, Idaho, Montana, and Utah take Kansas’ side of the debate.)

The question in front of the Court is whether a state can define its own reality within its borders or whether it must defer to the national standard backed by other state legislatures and experts.

Kahler v. Kansas

James Kahler killed his estranged wife, two daughters, and mother-in-law on Thanksgiving weekend of 2009. These facts are not disputed. But whether Kahler was sane when he did it is another story.

Kahler alleges that the state’s abolition of the insanity defense in 1995 was a knee-jerk reaction to a few high-profile insanity acquittals, especially the John Hinckley trial. After the attempted assassination of President Reagan in 1981, Hinckley was found not guilty by reason of insanity and confined in St. Elizabeth’s Hospital in Washington, D.C. He was allowed to make extended visits to his parents’ home beginning in 2007 and was released in 2016.

One commentator on the insanity defense described the Hinckley trial as “everything that is imperfect about the insanity defense: the undue power of forensic psychiatrists, the blurred lines of sanity, and the sensationalistic portrayals of what it means to be legally insane.”

Whether Hinckley or Kahler are legally culpable depends on the standard we apply: intent, moral knowledge, or control.

The oldest (and most stringent) standard is mens rea (“guilty mind”): is a person aware of what they are doing and intend to do it? If no, they are legally insane.

This was supplanted by the M’Naghten Rule in the late 1800s: does a person know what they were doing was wrong? Often referred to as the “right and wrong test,” the standard emerged from another attempted political assassination—of the British Prime Minister Robert Peel by Daniel M’Naghten in 1843. One could intend to do something (passing the mens rea test) but not know that it was wrong (failing the M’Naghten test).

The M’Naghten rule was then replaced in many U.S. jurisdictions during the twentieth century by the Model Penal Code: does a person have the “substantial capacity” to control their actions? This definition of insanity means that if a mental disease or defect results in the lack of control, then a person is legally insane.

Daniel M'Naghten in 1856
Source: Wikipedia

Every U.S. jurisdiction agrees that “a madmen is punished only by his madness” as Edward Coke phrased it in the 1600s, but they do not at all agree on which of these standards defines the limits of legal insanity.

Most states believe that individuals who cannot control themselves or cannot comprehend the rightness or wrongness of their act--even if they do it intentionally--are in fact insane. Kansas says they are not. As long as they can form intent they are not insane, ruling out much of what constitutes an insanity defense in most states.

Supreme Facts

Kahler’s brief to the Court argues that Kansas had a “misinformed reaction to a pair of headline-grabbing cases.”

Kansas retorts that “Kahler’s suggestion that the Kansas Legislature’s adoption of the mens rea approach was a knee-jerk, ‘misinformed reaction to a pair of headline-grabbing cases’ is wrong,” because reasonable people disagree about the realities of insanity.

The Court must decide whose version of reality is correct, and the Court is no stranger to the dilemmas of ruling on facts.

Our research on the role of social fact rulings demonstrates that a majority of the landmark Supreme Court cases of the twentieth century rely on a disputed fact ruling. The Court often has to determine not only what is right, but what is real.

Examples include whether marijuana is dangerous, whether men and women have the same attributes, or whether racism is still prevalent.

But how should the Court make factual judgments, given that they are experts in law, not many different areas of social and natural science?

We found that liberal Justices often rely on expert opinion, but conservative Justices are more likely to defer to the judgment of electoral branches of government.

This sets up a deep controversy about the legitimate foundations of facts: experts or electorates?

The Question of Expertise

In a telephone survey of Delaware residents conducted in 1983 (a year after Hinckley was acquitted), 91% of respondents agreed that “judges and juries have a hard time telling whether the defendants are really sane or insane.” Similar percentages agreed that “the insanity plea is a loophole that allows too many guilty people to go free” and that “the insanity defense allows dangerous people out on the streets.”

With these sort of prevailing beliefs—which are likely to be more extreme in conservative parts of the nation—why would legislators not listen to and enact the views of their constituents?

Perhaps the clearest argument is that they should listen to the minority of experts rather than the majority of citizens.

In the Kahler case, the American Psychiatric Association and the American Psychological Association submitted a brief to the Court supporting James Kahler.

According to the Psychiatrists’ Brief, “Experts for the prosecution and defense agreed that Kahler exhibited major depressive disorder, as well as obsessive-compulsive, borderline, paranoid, and narcissistic personality tendencies, and the defense expert opined that Kahler ‘felt compelled’ and ‘couldn’t refrain from doing what he did.’ The defense expert further found that Kahler might have suffered from ‘short-term dissociation’.”

Perhaps more importantly for the skeptics’ arguments, the psychiatrists assert that “the experience of forensic mental health professionals provides assurance that the insanity defense—which is rarely invoked—has not been and will not be subject to abuse.”

The psychiatrists want the Court to trust them. But will they?

A similar argument to trust experts was asserted in the recent cases on gerrymandering and fair elections. In Gill v. Whitford in 2018, the standard of expert judgment as a means of deciding social facts was roundly rejected.

In the oral arguments for that case, Chief Justice Roberts suggested that “you’re taking these issues away from democracy and you’re throwing them to the courts pursuant to, and it may be simply my educational background, but I can only describe as sociological gobbledygook.”

Will the Justices see the insanity defense as similar “psychological gobbledygook” or as legitimate expertise?

The Federalism of Facts

Perhaps the more accurate legal question is: Will the Justices allow the Kansas legislature to see the insanity defense as untrustworthy?

One of the core principles of the constitutional order is federalism: individual states have control over a wide range of policies that fall under the “police power,” or the ability to regulate society within their borders. This is especially true in the establishment of criminal violations and penalties, which vary tremendously from state to state. Even Kahler’s brief to the Court stipulates that “this Court does not lightly tread on a state’s administration of criminal justice.”

However, does this apply to facts? Do we insist that the realities recognized within most of the U.S. also apply in every state? Or do we allow the federalism of facts?

One of the most intriguing briefs in the Kahler case is from 113 professors of philosophy. The Philosophers' Brief argues that the minority must bow to the prevailing understanding of facts: “toleration and deference cannot go so far as to allow a government to perpetrate injustice of this sort. The Court should correct Kansas’s error.”

The philosophers are convinced that Kansas is wrong on the facts.

They assert without doubt that “the severely mentally disordered sometimes become convinced, as Mr. Kahler appears to have been, that their best, or even their only way forward, is to commit a serious crime.”

What authority or credential do the philosophers have in recognizing mental disorder? The Court will have to decide which group they believe is more easily fooled by false assertions of reality—philosophy professors or state legislators?

Tolerance, the philosophers assert, is for moral disagreements, but not empirical ones: “Tolerable moral disagreement must proceed against a backdrop of agreement about the nature of many descriptive features of persons that matter to the question of what justice requires.” In other words, tolerance is for morality, not reality. Judgments of facts (“descriptive features of persons”) must be in conformity across the nation.

Certainty may be in oversupply in regard to many perceptions of facts. And philosophers are not known to always respect empirical findings that they find inconvenient.

So the Kahler case will address many questions about how the Court should determine facts. If by expertise, which experts? Are the philosophers in the Kahler case experts? On what exactly? Are the psychiatrists experts whom we should trust? Instead of experts, should we trust electoral majorities to get facts right, through their elected representatives? And perhaps most relevant to the Supreme Court’s upcoming term, what should we do when states go rogue and assert facts of their own?

Is it sane or not to allow the federalism of facts?

More from Morgan Marietta Ph.D.
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