IRRESISTIBLE IMPULSE
A test applied in a criminal prosecution to determine whether a person accused of a crime was compelled by a mental disease to commit it and therefore cannot be held criminally responsible for her or his actions; in a WRONGFUL DEATH case, a compulsion to commit suicide created by the defendant.
In most jurisdictions, a person may defend
criminal charges on a ground of insanity. The
INSANITY DEFENSE comes in two main forms.
First, a defendant may argue that because of
mental disease or defect, he or she lacked the
capacity to distinguish right from wrong. This is
cognitive insanity.
Second, a defendant may argue that because
of mental disease or defect, she or he was unable
to act in conformance with the law. This is voli-
tional insanity, and it is known as the irresistible
impulse defense.Under this defense, a defendant
may be found not guilty by reason of insanity
even though she or he was capable of distin-
guishing right from wrong at the time of the
offense.
The success of an irresistible impulse
defense depends on the facts of the case. For
example, assume that a child has been molested.
If the child’s mother shoots and kills the sus-
pected molester, the mother could argue that she
was so enraged by the violation of her child that
she was unable to control her actions. The
mother need not have been diagnosed as men-
tally ill. Rather, she would need to show that she
was mentally ill at the time of the shooting, and
that the illness impaired her self-control.
Irresistible impulse emerged as a defense in
the nineteenth century, when psychoanalysts
formulated the concept of moral insanity to
describe the temporary inability of otherwise
sane persons to resist criminal behavior. Courts
began to recognize the condition as one that
rendered conduct involuntary and therefore not
suitable for punishment. For the better part of a
century, many states allowed both cognitive
insanity and irresistible impulse insanity as
defenses.
Congress and most states abolished the irre-
sistible impulse defense after John Hinckley was
acquitted on grounds of insanity for the
attempted assassination of President RONALD
REAGAN in 1981. Only a handful of states cur-
rently allow irresistible impulse as a defense to
criminal charges. These states permit it as a sup-
plement to the cognitive insanity defense, which
is the only insanity defense recognized in most
jurisdictions. On the federal level, Congress
abolished the irresistible impulse defense in the
Insanity Defense Reform Act of 1984 (18
U.S.C.A. §§ 1 note, 17).
In some states, the irresistible impulse defense
has never been adopted. In others, it has been
adopted and subsequently withdrawn. Where it
has been rejected, the reasons are generally the
same: to prevent sane persons from escaping lia-
bility simply because they were unable to control
their actions. In the words of one court, “There
are many appetites and passions which by long
indulgence acquire a mastery over men . . . but the
law is far from excusing criminal acts committed
under the impulse of such passions” (State v.
Brandon, 53 N.C. 463 [1862]).
Under the MODEL PENAL CODE definition of
irresistible impulse, a person may be found not
guilty by reason of insanity if, at the time of the
offense, he or she lacked “substantial capacity
either to appreciate the criminality of [the] con-
duct or to conform [the] conduct to the require-
ments of law” (§ 4.01(1) [1962]). The “lacked
substantial capacity” language creates a low
threshold for the defendant: in some states, the
defendant must allege complete impairment in
order to invoke the defense.
Irresistible impulse is also a factor in civil
actions. When a person commits suicide, sur-
vivors may sue for damages with a wrongful
death claim or similar action if they can show
that the suicide was caused by the actions of
another person. In such a case, the plaintiffs
must prove that the defendant caused a mental
condition that caused the decedent to experi-
