Insanity Defense

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Insanity Defense

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The Forensic Psychologist & The Insanity Defense

As part of their role within the legal system - in particular assessing criminal responsibility - a forensic psychologist may be asked to determine whether an accused individual can legitimately claim insanity as part of their defense.

As with other areas within the remit of the forensic psychologist, the insanity defense is often misrepresented and over stated in the popular media, which in turn has resulted in a skewed perception among the general public.

Contrary to public belief that the insanity defense is in essense a get out of jail card, the reality is that only a handful of defendants pursue an insanity defense and those that do rarely succeed. In percentage terms within felony cases, the insanity defense is employed around 1% of the time and within that 1% it is only successfully employed about a quarter of the time.

It's also worth noting that should a defendant be found not guility on the basis of insanity, they are likely to spend more time confined to a mental institution, than a sane individual in jail who has been convicted of a similar crime.

Further evidence that the insanity defense is hardly a legal loop hole can be seen in the major provisions of the Insanity-Defense Reform Act of 1984. Signed into law on October 12, 1984, this was the first comprehensive Federal legislation governing the insanity defense and the disposition of individuals suffering from a mental disease or defect who are involved in the criminal justice system. The more significant provisions of the act were that it:

1. Significantly modified the standard for insanity previously applied in the Federal courts.

2. Placed the burden of proof on the defendant to establish the defense by clear and convincing evidence.

3. Limited the scope of expert testimony on ultimate legal issues.

4. Eliminated the defense of diminished capacity.

5. Created a special verdict of "not guilty only by reason of insanity," which triggers a commitment proceeding.

6. Provided for Federal commitment of persons who become insane after having been found guilty or while serving a Federal prison sentence.

(Source US Attorneys Criminal Resource Manual)

The Insanity Defense: An Historical Perspective

For a more rounded understanding one needs to be aware of how the concept of the insanity defense developed historically.

Some of the earliest references to the criminally insane can be found in Roman law, which by and large advocated leniency, maintaining that madness was a punishment in itself. The issue of madness and criminal responsibility was being debated as far back as the 13th century with prominent writers of the time arguing that the ‘will to harm’ must be evident within a crime and the lack of such a will among the mad excused them of responsibility.

As soon as society began to engage with the idea that madness negated criminal responsibility, the study of mental illness within a forensic context was inevitable.

In 1603 Sir Edward Coke maintained that the madman ‘did not know what he did’, and as such did not actually display any criminal intent. This was important because form this point ‘insanity’ was judged exclusively in cognitive terms; namely did the accused know that what they were doing was wrong?

An early example of how this was encapsulated within the legal system is the wild beast test (1724) which stated that individuals exhibiting actions more like animal reflexes rather than moral choice were said not to be responsible for the crime they committed.

‘Totally deprived of his understanding and memory and doth not know what he is doing, no more than an infant, than a brute, or a wild beast.’

As a result of a number of high profile cases additional criteria for judging criminal responsibility came into play e.g. being able to distinguish between good and evil. In time this criteria became an independent measure of madness and juries had the option to find the accused not guilty by reason of insanity.

A key historical landmark in the legal relationship between insanity and responsibility can be traced back to the murder of the British Prime Minister’s secretary in 1841. The defendant Daniel M’Naughten was found not guilty on the grounds of insanity, a verdict which resulted in new legal guidelines being adopted in 1843 coined the M’Naughten rules.

It is said that Daniel M’Naghten believed he was being persecuted by the police, the Roman church and by the then Prime Minister Sir Robert Peel. On the 20th of January 1843 M’Naughten shot and killed the private secretary to the Prime Minister, mistaking the secretary for Peel.

M’Naghten was acquitted on the grounds that his delusions prevented him from controlling his actions; a decision which sparked outrage and led to judges of the case being asked to clarify the law on insanity. The judges’ responses became entrenched in what are known as the M’Naughten rules which stated that the accused should be presumed sane unless at the time of committing the offence he had a disease of the mind that caused them not to understand the nature and quality of the act or not understand that the act was wrong.

Learn More About The Insanity Defense

Insanity Evaluations

To understand the role of the forensic psychologist within the area of criminal responsibility, mental illness and the insanity defense make sure you watch the video on the main forensic psychologist page (about 12 minutes in).

The Insanity Defense: A Closer Look

This was the lead title in a series of articles produced by the Washington post in 1998. You can read these very informative editorials via the following links.

The Insanity Defense: A Closer Look

Kaczynski Resists the Insanity-Defense

Salvi Convicted of Murder in Shootings

John du Pont Found Guilty, Mentally Ill

Court: Insanity Defense Not a Right

Drawing a Clear Line Between Criminals and the Criminally Insane

Essential Reading

Insanity: Murder, Madness, and the Law by Charles Patrick Ewing

Book Description

In this book, Professor Ewing tackles the most complex of all legal/psychological issues: the insanity defense. It has been employed thousands of times, but there is still little understanding by lawyers and psychologists of its proper use.

By analyzing some of the most well-known insanity cases in legal history, this book sheds light on the particularities of this defense; when it is successful, and when it is a sham. The casebook is an established format in which to illuminate legal questions, and yet no such book exists yet for this topic. Professor Ewing will examine 20 of the most influential and controversial insanity cases, from the recent D.C. sniper trial to Jack Ruby's failed plea in his trial for the assassination of Lee Harvey Oswald.

The cases are all carefully chosen to illuminate different ways in which the courts have handled this defense. Throughout, the author will add his own analysis of the cases and the reasons for the verdict. This book will be an excellent introduction to the subject for students of law or forensic psychology, and a concise overview of the issues at stake for professionals in the field.

See following link for more details:

Insanity: Murder, Madness, and the Law

UK Visitors Click Here

Read FBI Profiling Classics on Kindle

This special Kindle collection consists primarily of the landmark articles written by members of the Behavioral Science Units, National Center for the Analysis of Violent Crime, at the FBI Academy. These seminal publications in the history of FBI profiling were released by the U.S. Department of Justice as part of the information on serial killers provided by the FBI's Training Division.

See following link for full details.

Information on Serial Killers

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