724 CHAPTER 16
The Insanity Defense: Current Issues
The federal requirements for the insanity defense have been narrowed, but ambigui-
ties about its defi nition have not yet been addressed by the courts. In particular, the
courts have yet to resolve two issues about how this defense can be applied:- whether the person knew the act was wrong (a moral question) versus illegal
(a legal question); and
CASE 16.1 • FROM THE OUTSIDE: The Insanity Defense
In 2001, Andrea Yates confessed to police that she drowned her fi ve children, ages 6
months to 7 years old, in her bathtub. She reported that she believed Satan was inside
her, and she drowned them to try to save them from hell. Yates’s lawyers said that she
had been psychotic at the time of the murders and that she did not know that her ac-
tions were wrong. (According to Texas state law, the key element of the insanity de-
fense is knowing that the actions were wrong at the time of the crime.) Her lawyers
pointed to her history of mental illness: two previous suicide attempts and four psy-
chiatric hospitalizations for schizophrenia and postpartum depression.
During her trial, an expert witness for the prosecution, psychiatrist Dr. Park Dietz,
agreed with previous witnesses that Yates had been psychotic at the time of the drown-
ings, but testifi ed that she was still able to know right from wrong and therefore not
insane under Texas law. To support his position, Dr. Dietz brought up the television
series Law and Order, which he had been told Yates had watched. Dietz, who also served
as a consultant to the producers of that television series, testifi ed that shortly before
she drowned her children, an episode of Law and Order aired that involved a woman
with postpartum depression who drowned her children in a bathtub and was declared
insane. Prosecutors used Dietz’s testimony about the television show to indicate that
Yates knew her actions were wrong (Greene et al., 2007).
It turns out, however, that no such episode had been aired; this error was discovered
after the jury convicted Yates of murder but before they began deliberating about her
punishment. Rather than declare a mistrial, the judge simply told the jurors about the
error. Yates was given a life sentence in prison. The appeals court ruled that a mistrial
had occurred, and Yates was retried. She was ultimately found not guilty by reason of
insanity and placed in a state mental hospital, where she will remain until she is no lon-
ger considered a danger to others or herself (Ewing & McCann, 2006).Test Legal StandardM’Naghten (1843) “Didn’t know what he or she was doing or didn’t
know it was wrong”Irresistible impulse (1886) “Could not control conduct”Durham (1954) “Criminal act was caused by mental illness”American Legal Institute (ALI; 1962) “Lacks substantial capacity to appreciate the
wrongfulness of the conduct or to control it”
[emphasis added]Present federal law (1984 and 1988) “Lacks capacity to appreciate the wrongfulness of his
or her conduct”Source: Meyer & Weaver, 2006, p. 123, which was adapted in part from Morris, 1986.Table 16.2 • Tests for the Insanity Defense Used Over Time
Andrea Yates, who was tried for murdering her
fi ve children, said she drowned them in order to
save them from hell. Her lawyers used the insan-
ity defense.AP Photo/Steve Ueckert, Pool