Attacks On The Insanity Defence Essay

This essay has a total of 3756 words and 16 pages.

Attacks On The Insanity Defence

Attacks on the Insanity Defence
The insanity defense refers to that branch of the concept of insanity which defines the
extent to which men accused of crimes may be relieved of criminal responsibility by virtue
of mental disease. The terms of such a defense are to be found in the instructions
presented by the trial judge to the jury at the close of a case. These instructions can be
drawn from any of several rules used in the determination of mental illness. The final
determination of mental illness rests solely on the jury who uses information drawn from
the testimony of "expert" witnesses, usually professionals in the field of psychology. The
net result of such a determination places an individual accordingly, be it placement in a
mental facility, incarceration, or outright release. Due to these aforementioned factors,
there are several problems raised by the existence of the insanity defense. Problems such
as the actual possibility of determining mental illness, justifiable placement of judged
"mentally ill" offenders, and the overall usefulness of such a defense. In all, I believe
that these problems, as well as others which will be mentioned later, lead us to the
conclusion that the insanity defense is useless and should be abolished entirely.

Insanity is a legal, not a medical definition. Therefore, mental illness and insanity are
not synonymous: only some mental illness constitutes insanity. Insanity, however, includes
not only mental illness but also mental deficiencies. Due to this, there are problems in
exactly how to apply a medical theory to a legal matter (Herman, 1983;128). The legal
concepts of mental illness and insanity raise questions in a conflict between what are
termed legalistic criminology and scientific criminology: mens rea, punishment v.
treatment, responsibility, and prisons v. hospitals. This debate seesaws to and fro amidst
a grey area between law and science. The major difficulty with a theory such as mental
illness is that it is just that, a theory. To scientists theories are a way of life, but
applied to the concept of law theories become somewhat dangerous. By applying a loose
theory such as mental illness to law we are in essence throwing the proverbial "monkey
wrench" into the wheels of justice.


At the center of the legal use of insanity lies the mens rea. Every crime involves a
physical act, or actus reus, and a mental act, or mens rea, the non-physical cause of
behavior. The mens rea is the mental element required for a crime, and if absent excuses
the defendant from criminal responsibility and punishment (Jeffery, 1985;49). The
difficulty here lies in analyzing the mens rea. In order to do this lawyers apply one of
several rules used by psychologists. These rules range from the Irresistible Impulse Test
to the M'Naghten Rule. Each of these rules approach mental illness/capacity in a different
way and in my opinion each falls short of actual proof. I will discuss each in detail.

The M'Naghten Rule The M'Naghten Rule, also known as the right-wrong test, arose in 1843
during the trial of Daniel M'Naghten who argued that he was not criminally responsible for
his actions because he suffered from delusions at the time of the killing. The M'Naghten
Rule reads: A defendant may be excused from criminal responsibility if at the time of the
commission of the act the party accused was laboring under such a defect of reason, from a
disease of the mind, as not to know the nature and the quality of the act he was doing, or
if he did know it, that he did not know that he was doing what was wrong. Thus, according
to the rule, a person is basically insane if he or she is unable to distinguish between
right and wrong as a result of some mental disability.

Criticism of the M'Naghten Rule has come from both legal and medical professions. Many
criticize that the test is unsound in its view of human psychology. Psychiatry, it is
argued, views the human personality as an integrated entity, not divisible into separate
compartments of reason, emotion, or volition (Herman, 1983;138). Additionally, the test is
criticized for defining responsibility solely in terms of cognition. While cognitive
symptoms may reveal disorder, they alone are not sufficient to give an adequate picture of
such a disorder or determine responsibility. Also, it has been shown that individuals
deemed insane by psychologists have possessed the ability to differentiate right from
wrong. I believe that the major weakness of this test, however, lies in the fact that
courts are unable to make clear determinations of terms such as disease of the mind, know,
and the nature and quality of the act.

The Irresistible Impulse Test This rule excludes from criminal responsibility a person
whose mental disease makes it impossible to control personal conduct. Unlike the M'Naghten
Rule, the criminal may be able to distinguish between right and wrong, but may be unable
to exercise self-control because of a disabling mental condition. Normally this test is
combined with the M'Naghten Rule. Many of the criticisms of the Irresistible Impulse Test
center around the claim that the view of volition is so extremely narrow that it can be
misleading. Just as the M'Naghten Rule focused on cognition rather than the function of
the person in an integrated fashion, the Irresistible Impulse Test abstracts the element
of volition in a way that fails to assess a person's function in terms of an integrated
personality. Additionally, it has been asserted that the concept at best has medical
significance in only minor crimes resulting from obsession-compulsion, and that seldom, if
ever, can it be shown that this disorder results in the commission of a major crime
(Seigel 1993;144). Such a claim is subject to the objection that it cannot be conclusively
proven. Interestingly, it has been shown by many psychiatric authorities that no homicidal
or suicidal crime ever results from obsession-compulsion neurosis.

Another criticism of this test is the difficulty, if not the impossibility, of proving the
irresistibility of the impulse, which the definition of the test requires. The jury, as I
said earlier, has the final decision, and is faced with deciding when the impulse was
irresistible and when it was merely unresisted, a task that psychiatrists suggest is
impossible to perform. We are also able to argue that the test is one of volition. It is
too narrow in that it fails to recognize mental illness characterized by brooding and
reflection (Herman 1983;140). The test is misleading in its suggestion that where a crime
is committed as a result of emotional disorder due to insanity, it must be sudden and

The Durham Rule The Durham Rule, also known as the Products Test, is based on the
contention that insanity represents many personality factors, all of which may not be
present in every case. It was brought about by Judge David Bazelon in the case of Durham
v. U.S. who rejected the M'Naghten Rule and stated that the accused is not criminally
responsible if the unlawful act was the product of mental disease or defect.

The primary problem with this rule of course lies in its meaning. Again it is impossible
for us to define mental disease or defect, and product does not give the jury a reliable
standard by which to base a decision. It is unnecessary to offer further criticism, for my
purpose I believe this attempt fails at it's onset.

The Substantial Capacity Test Another test is termed the Substantial Capacity Test which
focuses on the reason and will of the accused. It states that at the time of the crime, as
a result of some mental disease or defect, the accused lacked the substantial capacity to
(a) appreciate the wrongfulness of their conduct or (b) conform their conduct to the
requirements of the law. This test is disputable in the fact that it is not only
impossible to prove capacity of reason or will, but to even test such abstracts seems
absurd. Additionally, the term "substantial capacity" lies question in that it is an
abstract impossible to define.


The meaning of insanity is the legal definition as put forth in a rule such as the
M'naghten Rule or whatever school of thought is in use on any given day. The legal test is
applied in an adversary system which pitches lawyer against psychiatrist and psychiatrist
against psychiatrist. Because of this, the psychiatrist is often perceived not as a
scientist but a partisan for the side which is paying for his testimony (Jeffery,
1985;56). The major problem in this case being that the use of a neutral expert is
impossible to implement. In the end the determination of insanity is a layman's decision
since it is the jury which ultimately decides whether the defendant is sane or insane.
This of course is ludicrous since professional scientists cannot agree on the meaning of
mental illness. How can a layman make such a decision especially after listening to
contradictory testimony which is manipulated by opposing lawyers. I believe that the major
problem that we can point out here is in the futility of asking psychiatrists to testify
in terms of legal concepts of insanity. The psychiatrist finds himself in a double bind:
he has no medical definition of mental illness and he must answer questions from lawyers
concerning legal insanity, right and wrong, and irresistible impulses. As stated by
Packer: "The insanity defense cannot tolerate psychiatric testimony since the ethical
foundations of the criminal law are rooted in beliefs about human rationality,
deterribility, and free will. These are articles of moral faith rather than scientific


In the insanity defense we have no variable independent of the criminal behavior we are
studying. Insanity refers to a class of behaviors known by observing the behavior of the
patient, and criminality is a class of behavior likewise known by observing the behavior
of the defendant. We are involved in classification and labels. Where we have one class of
behaviors labeled as schizophrenia, and the other class labeled as crimes, what we have
are two co-existing classes of behavior in the same individual, and not a cause or effect
relationship (Simon, 1988;47). A person can be Catholic and commit a robbery without a
casual relationship existing; likewise, a person can be schizophrenic and a robber without
a casual relationship existing between the two classes of behavior. Coexistence does not
show a casual relationship. Behavior cannot cause behavior.

What we must do, in order to prove a relationship between mental illness and criminal
behavior is produce some independent link between the two classes of behavior on a
biochemical level. We must have a definition of mental illness independent of the
behavioral symptoms in order to establish a casual relationship between crime and mental
illness. There is such a view and it is termed the Biological Psychiatric view. The view
basically states that there is some defect or malfunction in the actual make-up of the
brain of an individual which causes schizophrenia. This same defect then causes the
criminal behavior such as robbery or murder. The problem here is that we have no actual
way of mapping the brain and conclusively determining exactly what portion thereof is
responsible for either type of behavior much less that one area is responsible for both.
In essence even if true this theory is unprovable.

There is also a statistical relationship between crime and mental illness. Guttmacker and
Weihofen found 1.5 percent of the criminal population psychotic, 2.4 percent mentally
defective, 6.9 percent neurotic, and 11.2 percent psychopathic (Jeffery, 1985:66). These
figures are very unconvincing. Additionally they are based on old diagnostic categories
and procedures which are most unreliable. Also, the meaning of neurotic or psychotic or
psychopathic is uncertain within the context of these studies and they do not refer to
modern biological categories of brain disease. Terms such as insanity, mental illness, and
Continues for 8 more pages >>