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The Insanity Plea as a Defense


New York residents may wonder how the insanity defense works and how common it is. Although many people who commit violent crimes are mentally ill, mental illness is not the same as insanity from a legal standpoint, and the National Institute of Mental Health found that it is used in only one out of every 100 cases in county court. Furthermore, it is only successful about 25 percent of the time.

Among the people who have used the insanity defense are John Hinckley, Jr., who attempted to shoot President Ronald Reagan, and Andrea Yates, a mother who drowned her children. However, it was unsuccessful for notorious serial killers Jeffrey Dahmer and John Wayne Gacy because it was determined that they knew the difference between right and wrong at the time of their actions. This is often the crux in determining the success of an insanity defense. A person can be mentally ill from a medical standpoint but still understand that the act that is being committed is wrong.

James Holmes, who opened fire in a Colorado movie theater in 2012, has also pleaded not guilty by reason of insanity. A favorable verdict means he will go to a mental health facility instead of facing the death penalty.

A person who is facing charges for a violent felony may wish to plead insanity if they were unable to distinguish right from wrong at the time the act occurred. One advantage of this plea is that defendants will be in a better position to receive the treatment from their mental health that they need. Depending on the charges and their progress, they may eventually be released from the mental health facility if it is determined that they no longer pose a threat to society. A criminal defense attorney can provide a further analysis to a client of the consequences of such a plea.