Despite the fact that the definitions of legal insanity are different in the states, basically a person is thought to be insane and not responsible for the offense under the certain condition that at the time of committing a crime he was not able to realize and admit the wrongfulness of his acts, as the result of mental disease he suffered from.
The fact that a person is not considered to be guilty, under the circumstances described above, can be proved with the absence of the most essential part of many offenses, which is the intention of the accused. However, mental disease is not the only component that forms a legal insanity defense. Also, the accused has to prove the defense of insanity with the help of persuading evidence.
The history of the insanity defense dates back to 1843 when Daniel M’Naghten tried to assassinate the British prime minister and eventually was admitted not guilty because he appeared to be insane at the time of attempted murder. After this case the strict definition of legal insanity was created and called the M’Naghten Rule. This Rule said that a person was not insane from the legal point of view unless he was not able to estimate his surroundings due to the strong mental delusion.
As it has been mentioned, nowadays the standard for proving legal insanity is different. It varies from state to state. If we take a look at California in particular, we will see that M’Naghten Rule is currently used there. California law claims that a person is legally insane if he or she doesn’t understand the nature of his or her actions and can’t distinguish between right and wrong. California law requires that the accused party proved his or her insanity by providing the court with convincing evidence. Having estimated the evidence the party provides, the court decides if the accused party was legally insane at the time of committing a crime. If so, this party is pronounced not guilty due to his or her insanity.
References
Arthur H. Coleman, MD, JD, and Arthur T. Davidson, MD, JD. (1978). M’Naghten Rule:the right or wrong of criminal law. Journal of the National Medical Association.Retrieved from ncbi.nlm.nih.gov
Charles Montaldo. (2012). The insanity defense. Retrieved from …