What it means when someone pleads not guilty by grounds of insanity

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Like the majority of states in the country, Arizona allows the insanity defense to be used during criminal court proceedings. A few states, such as Idaho, Kansas, Montana, and Utah, do not allow the defense. However, these states, aside from Kansas, do allow for a guilty but insane verdict to be given. Anyone who is charged with a crime in Arizona can seek help from a Phoenix Criminal Attorney .

An attorney can explain the defense in detail, and tell you what to expect. Here is a simplified look at the insanity defense, and what it can mean.

The roots of the insanity defense

The first time that the insanity defense was recognised was as far back as the sixteenth century. It was at this time that it was noted in English law that if someone killed another person during a period of lunacy they should not be held accountable. In 1724 the wild beast test was introduced into English law. This was a test which meant that a person could not be convicted of a crime if they did not understand what they had done any better than “an infant, a brute or a wild beast”.

The insanity defense today

Obviously, we do not use the same language today as was used all those years ago in England. But, the basic premise of the insanity defense remains the same. It’s about whether or not someone was legally insane at the time they committed a crime. If it’s found that they were insane they can be found not guilty by grounds of insanity, or they may be found guilty but be given a reduced sentence.

How legal insanity is determined

There are several tests which can be used in order to determine whether a defendant is legally insane. One of the most common tests in use is the M’Naghten Rule. This was first introduced by the House of Lords in England, in the middle of the nineteenth century. The rule is slightly different, depending on which state is involved. But, the basic premise is that it needs to be proven that the defendant did not understand the nature of the crime, or did not understand right from wrong, due to a mental illness or incapacity, when the crime was committed.

There have been several criticisms raised, regarding the use of this rule. One of the main issues is that it can enable a person who has a mental illness to escape a jail sentence, even if the illness did not have a significant bearing on the crime that was committed. There is also some concern that the rule does not take sufficient account of the danger that a person poses to the community as a whole.

It’s not common for a plea of not guilty by grounds of insanity to be accepted, but it does happen. That being said, this can only happen when the defendant is proven to be criminally insane at the time that the crime was committed.