Anyone with half a brain knows that you’d have to be crazy to murder someone. So why doesn’t the insanity defense get used more often? Because legal insanity is more difficult to establish than what the rest of us know is the act of a clearly insane human being. I mean, come on, is there any doubt any longer that George W. Bush is insane? Just try proving that to his fellow Republican politicians whose own mental stability is certainly in doubt as well. Legal insanity in regard to killing another human being is all about proving beyond a reasonable doubt that the suspect is actually incapable of distinguishing the difference between what is right and what is wrong. (Hey, we’re back to Bush!) The insanity please in a court of law typically is based upon what is known as the M’Naughten rule. The M’Naughten rule, in turn, is based on the concept that if a person did in fact commit a crime without being able to distinguish the difference between right and wrong-was utterly incapable of understanding the full extent of the act-he or she should not be found guilty of committing the crime. Of course, some courts do not take the M’Naughten rule into consideration in cases of the insanity plea. In those case, the defendant may be ruled insane if it can be proved that he did not possess the capacity to fully understand the criminality of his actions.
In some states, the defendant who pleas legal insanity may be able to escape taking on conscious responsibility for the crime if he can instead prove that he gave in to a temporary and irresistible impulse that drove him to commit an act that he otherwise while in a stable state of mind would not have committed. In other words, temporary insanity. The reasoning behind temporary insanity is that it does take into consideration the authenticity of people losing control of their natural inhibitions when subjected to great stress. Think of temporary insanity in terms of bending a stick. The stick can take on tremendous stress for an extended period of time, but it only takes an infinitesimal addition to cause it to crack apart. That irresistible impulse can come in guise of one too many beatings, one too many outrages of society or circumstances that drive one to the point of desperation.
Another interesting quirk is that a defendant need not actually be considered legally insane at the time of his trial. Nor does his insanity necessarily have to fit any medical definition of insanity in perfect symmetry. The testimony of doctors from both the defense and prosecution will confuse the jury anyway so all they really need do is decide if the mental state of the defendant fits the legal requirements of insanity.