'You Can't See Why on an fMRI'

What science can, and can't, tell us about the insanity defense

Brian Doherty from the July 2007 issue

(Page 2 of 4)

Many others disagreed, including the second jury. Such people thought that the diagnosis of mental illness was sufficient proof that Yates was beyond the realm of moral choice—that she had the inability to understand right and wrong required by Texas’ insanity defense. To make this case, they referred frequently to recent advances in neuroscience.

As long ago as 1985, serious, scientific books about the insanity defense were asserting that, as the criminologist C.R. Jeffery wrote in the collection Attacks on the Insanity Defense, “it is now possible to prove the presence or absence of schizophrenia or sociopathy through neurological tests of the brain.” Today we are told in venues high and low that advanced tools of brain study are highly relevant to our understanding of human behavior, in or out of court. An article by Deborah Denno in the Duke Journal of Gender Law and Policy complained that juries in general lack understanding of the “physiological underpinnings of…psychoses.” In January Time declared that “neuroscientists can almost read people’s thoughts.” Last year The New York Times’ Benedict Carey wrote—exaggerating for effect, but with no doubt that he was exaggerating a widespread popular understanding—that “At this rate, it seems that neuroscientists will soon pinpoint the regions in the brain where mediocre poetry is generated, where high school grudges are lodged, where sarcasm blooms like a red rose.” A 2005 op-ed in the Hackensack, New Jersey, Record tried to explain what was going on with Yates by declaring, “Brain scans apparently have shown differences in a postpartum brain from other brains.”

Having written about the case as it unfolded, I know from my own experience that to suggest Yates be considered morally and legally responsible for her actions invites widespread condemnation. Whether in emails from far and wide or in heated bar arguments, I’ve been derided as a Neanderthal who is ignorant of modern psychiatry, neuroscience, and the true nature of mental illness.

It’s interesting, then, that none of the celebrated objective brain-analyzing technologies—not functional magnetic resonance imaging (fMRI), not positron emission tomography (PET), not computed axial tomography (CAT)—had any bearing on the Yates case as it was presented in court, or on insanity defense cases in general. Neither did any of those techniques play a role in her dealings with medical professionals.

The diagnosis and judgment of Yates were based on old-fashioned methods: talking to her and contemplating her statements and actions. For the most part, what scientific expert witnesses in such cases do is to interpret actions, not analyze objective facts. Neuroscientific advances have done nothing to change that, marking interesting and perhaps permanent gaps between psychiatry and the law.

Critics on the Stand
The expert-witness debates in the Yates trials thus seemed more like literary criticism than medical science. The dueling explanations of what was going on in Yates’ head that grim morning were not based on looking into that head with tools that only a professional would be competent to use and interpret for a jury. They were based on observations and interpretations of the sort that every reader posting on CourtTV.com was doing, and with similar conclusions.

In his testimony in Yates’ first trial, Park Dietz argued that, given her intense religiosity, Yates’ claim that the command to drown her children came from Satan proves she knew it was an evil impulse. When Dietz suggested to Yates during their interview session, “You saw it as a sin that you were going to commit,” she answered simply, “Yes.” For Dietz, the facts that Yates called the cops right after killing her kids and said to one of them that she was a bad mother who deserved to be punished showed she knew it was wrong to drown her children.

Testifying for the defense, Phillip Resnick, director of the forensic division at Case Western Reserve University, pointed out that Yates also said at a different time that she was sure drowning her children now—before, say, young Paul could become the mute homosexual prostitute she obsessively fantasized he would become—would guarantee them entrance to heaven. According to Resnick, this showed she meant to help, not harm, her children and thus did not know the legal difference between right and wrong, as required to convict her. In fact, he argued, Yates believed what she was doing was right, even if she understood society would punish her for it.

By Resnick’s account, Yates recognized that her act was against the laws of man but believed it was in accord with the law of God because it would ensure her children an eternity in paradise. She had told Resnick she was tormented by the fact that her children seemed to be growing into kids who were “not righteous,” who were distant from God. Killing her children would serve their long-term well-being by ensuring that they “did not stumble.” As Resnick said on the stand, “Mrs. Yates had a choice to make: to allow her children to end up burning in hell for eternity or to take their lives on earth.”

Michael Welner, an expert witness for the prosecution in the second trial, offered an alternative interpretation. “It is my professional opinion, with a reasonable degree of psychiatric certainty,” he said in a written report offered to the court, “that the psychotic aspects of Andrea Yates at the time of her crimes included delusional self-reproach of her failure as a parent, and referential thinking amplifying her failures, and her feelings that she needed to be punished. Other symptoms developed when she was buffeted with the enormity of her actions, including hallucinations, irrational identification with Satan, disorganized speech, labile emotions, and bizarre behavior.” Welner finally pointed out that “Andrea Yates did not say, ‘I saved the children,’ or ‘I ushered them into the next world,’ ‘I just sent the children to heaven,’ or ‘I just saved my children,’ she said ‘I killed my children’—twice” (emphasis in original).

In the first trial, the jury was convinced by one set of arguments about the motives of the lead character in the drama, and it found Yates guilty. In the second trial, a different jury was convinced by a different version of the narrative, and it found her not guilty by reason of insanity. But neither narrative seems to have anything to do with medical expertise.

As the psychologists Charles Patrick Ewing and Joseph T. McCann revealed in their 2006 book Minds on Trial, psychiatric testimony often consists of making closing arguments for the defense (or prosecution) under the guise of science, rather than applying specific expert knowledge. It may amount to accepting the sincerity of a defendant’s claim that he committed his crime for a seemingly insane reason, such as a supernatural command. Or it may mean offering an alternative explanation for the crime that makes it seem as if the defendant doesn’t meet the legal definition of insanity. Ewing and McCann ultimately conclude that there are “sometimes serious questions as to whether [professional psychiatric] input has actually helped or hindered the justice system.”

A History of Insanity
The belief that certain mental states remove defendants from the realm of legal responsibility goes back to at least 1505. In modern America, a handful of standards have jockeyed for position to define insanity and legal responsibility. The first was the “M’Naghten rule,” named after an 1843 British case involving a Scottish woodcutter, Daniel M’Naghten, who tried to kill Prime Minister Robert Peel but fatally shot Peel’s secretary instead. M’Naghten, who insisted he was trying to stop Peel from killing him, was acquitted. According to the standard that arose from that case—nowadays still the basis for the insanity defense in nearly half the states in the U.S.—a defendant should not be held legally responsible for his crime if, due to “a defect of reason” caused by a “disease of the mind,” he either did not know what he was doing or did not know it was wrong.

From the 1950s through the early ’80s, American insanity defense law passed through several stages with dueling standards. Then came the trial of John Hinckley, the would-be murderer of Ronald Reagan, who was found not guilty by reason of insanity in 1984. The ensuing backlash led to the Insanity Defense Reform Act of 1984, which changed the federal standards for the insanity defense. About half the states also adjusted their insanity standards in the wake of Hinckley. For the most part, the federal statute and the state-level reforms eliminated a consideration from a previous standard that the defendant be mentally able to conform his conduct to the law, and declared that the mental illness had to be “severe.”

The variations in state standards for the insanity defense led to a 2006 Supreme Court case, Clark v. Arizona, in which a majority of justices seemed to agree that the judicial system doesn’t necessarily have to follow the guidance of psychiatric experts. The case involved Eric Clark, a young man from Arizona who claimed to believe, as the Supreme Court put it, “that ‘aliens’ (some impersonating government agents) were trying to kill him and that bullets were the only way to stop them.”