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Law and Crime
Not Guilty by Reason of Insanity
What it means to be insane according to the law.
Posted February 6, 2020 Reviewed by Chloe Williams
A horrific murder occurs. The defendant is caught and pleads not guilty by reason of insanity (NGRI). If the plea is successful, is someone getting away with murder without legal consequences? Well, not exactly.
An insanity defense is based on the theory that the majority of individuals can choose to follow the law or not. A few individuals cannot be held accountable because mental illness or defect deprives them of making a rational and voluntary choice. Because of this deficit, they are given special treatment as opposed to prison.
NGRI is a legal defense. It addresses mental status at the time of the alleged crime. Competency to stand trial has to do with a person’s present mental status at the time that person returns to court.
Anyone who commits a crime can meet the standard of mental illness (following state law). Not everyone meets the standard of NGRI just because they have a mental illness.
Why then are we so fascinated by mental illness and crime? Well, for one, we are fascinated by the court system. Watch TV—we are inundated by courtroom shows like CSI, Law and Order, Criminal Minds. We are bombarded by information about courts, some accurate, some not. There is intense coverage on legal cases where the insanity defense was successful—John Hinckley and Andrea Yates are two famous cases. Newsworthy coverage suggests NGRI can be counted on as a highly successful defense strategy. This presumption is not correct.
In fact, the insanity defense is used in only 1 percent of all criminal proceedings, and its success rate is only 25 percent of that 1 percent. Therefore, less than 1 in 400 defendants are found not guilty by reason of insanity in this country. A small sample for such intensive coverage that leads us to believe NGRI is used often as a defense. Based on current statistics, it is not and when used is rarely successful.
In general, every crime involves three elements: actus reus, the act or conduct; mens rea, the individual's mental state at the time of the act, and third, there has to be a connection between the act and the effect.
With most offenses, a person is only not guilty of a crime if he or she actually didn’t intend to commit the crime. If a driver accidentally hits someone with their car they are not guilty of vehicular homicide. However, if the driver had the intention to harm the person, the action is the same, but the intention is different. Mental illness can alter a person's perception of reality so that he or she does not realize the criminal nature of his or her actions or has no choice but to commit the crime. When this is the case, certain courts believe the person lacks this element of intention necessary for criminal guilt.
States rely on four different ways of determining a defendant is legally insane: M'Naghten test, Durham Rule, the Irresistible Impulse Test, and the Model Penal Code.
Using the parameters of the M’Naghten test, a defendant is unable to distinguish between right and wrong or otherwise didn't understand what they did because of a "disease of the mind.” The burden is on the defendant. Florida, Texas, Iowa, and Louisiana use this standard, to name a few.
The Durham rule, product test or product defect rule, is a rule in a criminal case by which a jury may determine a defendant is not guilty by reason of insanity because a criminal act was the product of a mental disease.
Using the Irresistible Impulse test, the law defines an insane defendant as unable to control their impulses leading to the commission of a criminal act. Those who use this test, the defense is known as a defense by excuse, some sort of insanity, in which the defendant argues that they should not be held criminally liable for their actions that broke the law, because they could not control those actions, even if they knew them to be wrong. New Mexico, Ohio, and Virginia use this test for insanity
Under the Model Penal Code definition of irresistible impulse, a person may be found not guilty by reason of insanity if, at the time of the offense, he or she lacked "substantial capacity either to appreciate the criminality of [the] conduct or to conform [the] conduct to the requirements of law."
On the surface, the collection of the information necessary to use an insanity defense appears to be straight forward, but in fact, this kind of defense has been controversial.
In 2005, four years after Andrea Yates faced the death penalty for the drowning deaths of her five children, a second jury found her not guilty by reason of insanity. In the second trial, jurors deliberated for 13 hours before finding that Yates did not know her crime was wrong because of her long history of mental illness.
Prior to the murders, Yates had endured multiple psychiatric hospitalizations and two suicide attempts before she drowned her children. She was later diagnosed with postpartum depression with psychotic features and schizophrenia. One of the forensic psychiatrists testified that Yates did not know that killing her children was wrong because she believed she was saving them from hell. Yates was delusional and believed her children would grow up to be criminals because she had ruined them, as their mother. She was returning them from earth to heaven.
After John Hinckley was found NGRI for the shooting of President Regan in 1982, the public response was outrage. To convict Hinckley, the prosecution had to prove the defendant was either not mentally ill, or if he was, that he could still appreciate the wrongfulness of his actions and conform to the law.
Members of the House and Senate held hearings on the use of the insanity defense within a month of the verdict. First, the burden of proving insanity shifted to the defendant. In virtually every criminal case, the prosecution must prove that the defendant had a particular intent, acknowledging that he or she committed the alleged act but arguing that it appeared to be necessary in order to defend themselves from harm.
In addition to shifting the burden in insanity cases, Congress also significantly narrowed the defense. Federal legislation passed in 1984 required the defendant to prove a "severe" mental disease and eliminated the "volitional" or "control" aspect of the insanity defense. After 1984, a federal defendant had to prove that the "severe" mental disease made him "unable to appreciate the nature and quality or the wrongfulness of his acts." This is known as an affirmative defense. It is equivalent to the self-defense.
James Holmes killed 12 people and wounded 58 when he opened fire during a midnight showing of The Dark Knight Rises, a Batman movie, in the Denver suburb of Aurora on July 20, 2012. Twelve other people were injured in the scramble to escape.
Holmes was mentally ill at the time of the killings—diagnosed with a severe form of schizophrenia. Despite this illness, Holmes knew his elaborately planned ambush was illegal and morally wrong, but he could still form criminal intent, which meant under state law he was sane. His planning, choice of time, location, weaponry, and execution were meticulously placed in motion.
In the case of Holmes, as he initially pleaded not guilty, the only defense that was available to him was NGRI—an acknowledgment that the person committed the alleged act but arguing that it appeared to be necessary in order to defend oneself from harm because of mental illness. He was sentenced to two consecutive life sentences plus 3,318 years without parole.
It is important to remember that NGRI is simply a legal term and not a diagnosis.
