If an accused individual can successfully plead insanity as a part of his or her defense against murder charges, it might be possible to achieve a verdict of not guilty. In other outcomes, a successful insanity plea might result in a conviction, but achieve a dramatic reduction in sentencing. In the article that follows, we will discuss the history of pleading insanity in addition to the various types of insanity individuals might plead.
The first time that insanity was recognized as a viable legal defense was in 1581. According to an English legal treatise, “mad men” and “lunatics” cannot be considered accountable if they kill someone. In England, during the 1700s, they further developed the “wild beast” test to define insanity. If, for example, the alleged murderer did not understand his or her crime better than a baby or an animal could, then he or she could not be convicted.
In modern times, and depending on the state in which the incident occurred, courts use several new types of tests to determine insanity. The “M’Naghten Rule” says that alleged murderers cannot be convicted if they did not understand what they did and/or they were unable to distinguish between right and wrong as a result of a diseased mind. The “Irresistible Impulse” test relates to an individual not being able to control his or her impulses due to a diseased mind.
The “Durham Rule” seeks to claim that the defendant committed his or her criminal act due to a mental defect. Finally, the “Model Penal Code” test uses a clinical diagnosis of mental defect to show that a particular defendant did not understand the nature of his or her acts, or was unable to act according to the law.
Choosing which type of insanity defense to plead will largely depend on the state where the incident occurred and the facts and circumstances surrounding the murder charges. Obviously, pleading insanity is not a viable defense in all situations, but when it applies to a particular case and it is successfully utilized, it can be particularly effective.
Source: Findlaw, “Insanity defense,” accessed May. 26, 2015