An Overview of the Insanity Defense
In order to be completely excused from criminal liability, a criminal defendant may claim the defense of legal insanity. In order to be considered legally insane, a criminal defendant's mental issue must conform to legal tests that differ from state to state.
If it is established that the defendant was legally insane at the time the crime took place, he will be completely excused. Upon a finding a mental insanity, the court will generally order the defendant to be placed in a mental hospital.
How Can a Criminal Defendant Establish an Insanity Defense?
In order to establish an insanity defense, the defendant must satisfy one of the following tests, depending upon the jurisdiction where the crime was committed:
- M'Naghten Test: A criminal defendant either 1) did not understand his actions' nature and quality, or 2) lacked knowledge of the wrongfulness of his actions.
- Irresistible Impulse Test: A criminal defendant couldn't control his actions. In another words, this test emphasizes defendant's volitional incapacity.
- American Law Institute Test: A criminal defendant lacked substantial capacity to understand wrongfulness of his actions or control them. Here, a total lack of understanding or control is not required. The defendant must have been substantially unable to understand or control his actions.
- Durham Test: A criminal defendant would not have committed the crime "but for" his mental disease, of which his crime was a product. With the exception of New Hampshire, this test is not in use today.
- Federal Test: As a result of several mental disease, criminal defendant couldn't understand wrongfulness of his actions or couldn't control them. This test is similar to the one used by American Law Institute. However, the defendant has to prove "severity" of his mental illness and do so by clear and convincing evidence, a higher standard then preponderance of evidence.
Note that in most jurisdictions, a criminal defendant has the initial burden of producing evidence of legal insanity, which must be proven by a preponderance of the evidence. In some states, the prosecution must prove beyond a reasonable doubt that the defendant was sane when he committed the crime.
What is a Diminished Capacity and How Does it Differ from Insanity?
Some states recognize a defense of "diminished capacity," which is basically a mental defect that falls short of insanity. Diminished capacity is not a complete defense. It usually serves to mitigate a criminal defendant's conviction to a less serious charge. A criminal defendant may claim diminished capacity in connection with a mental defect as well as intoxication. In jurisdictions where diminished capacity is recognized, it often helps establish a defense for specific intent crimes.
Does Incompetency to Stand Trial Serve as a Defense?
The question of a criminal defendant's competency to stand trial is separate from the issue of his insanity at the time the crime was committed. If a defendant lacks the capacity to assist his lawyer or understand the proceedings brought against him, due process prevents his trial, conviction, and sentencing. However, if a criminal defendant regains competence, proceedings may resume. Finally, while the jury must decide the issue of the defendant's insanity defense, a judge makes the determination regarding his competency to stand trial.
Do I Need an Attorney's Help?
If you are faced with criminal charges, a qualified criminal defense attorney will help you understand the defenses available to your case. An attorney will help you develop a strategy for your defense and will represent you during trial.
Consult a Lawyer - Present Your Case Now!
Last Modified: 09-10-2013 10:19 AM PDT
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