Nearly everyone has heard of cases where violent criminals have pleaded not guilty by reason of insanity and presumably avoided the consequences of their actions.  Many assume that means all the defendant needs to do is claim he is insane, act weird during the trial and walk away without a sentence. This causes many people to ask, "Can anyone claim temporary insanity to avoid the consequences of a crime?" Technically, you could make the plea, but it will likely take more than a few shenanigans in court to convince the judge 

What is an insanity plea?

An insanity plea makes the case that the accused should not be held responsible for his actions because he was either insane at the time of the crime, could not distinguish right from wrong, or could not control his behavior due to a diagnosed psychiatric disorder. That means the psychiatric disorder must be directly related to the behavior. For example, if the accused suffers from delusions and hallucinations due to a diagnosis of schizophrenia that causes him to believe he is under attack and he reacts with violence, he may be found not guilty by reason of insanity. However, it is unlikely that he could mount a legitimate defense if his diagnosed psychiatric disorder is an eating disorder.

Who verifies the psychiatric disorder?

What happens to the defendant once he pleads not guilty by reason of insanity depends on whether the insanity was temporary or ongoing. If the defendant claims (or the court determines there is reason to suspect) the condition is ongoing, a trial is held to determine whether he has the mental capacity to stand trial. This includes testimony from psychiatrists, medical doctors, caregivers and other professionals. If the defendant is found unfit to stand trial by reason of psychiatric condition, he is sent to a psychiatric facility until such time as he is deemed fit to stand trial.

According to Law.com, if a defendant enters a plea of not guilty by reason of insanity, claiming temporary insanity at the time the crime, a trial must take place to determine whether the person could distinguish right from wrong (or control his behavior) at the time of the crime. This trial typically includes evaluations and testimony by independent psychiatrists and psychologists. Sometimes the testimony is heard by the judge alone, but is often presented to a jury to decide the validity of the claim of insanity.

Courts typically use one or more of four legal tests to determine if the defendant should be held responsible for his actions.

1. The "M'Naghten Rule" - the person does not understand why what he did was wrong, or is unable to tell right from wrong due to a disease of the mind.
2. The "Irresistible Impulse" Test -  A mental disease caused impulses the person was unable to control.
3. The "Durham Rule" - A mental defect caused the person to commit the crime. A clinical diagnosis is not required.
4. The "Model Penal Code" - A diagnosed mental disorder prevented the person from understanding that his actions violate the law or prevented him from following the law.

What happens if the defendant is found guilty?

Many people mistakenly believe that criminals who are determined to be not guilty by reason of insanity are free to return to society with no consequences. While this could happen, it is not likely in violent or serious crimes. Sometimes the convicted person receives a lighter sentence, other times he is required to participate in a psychological treatment program. The consequences differ according to the state regulations and the nature of the crime.

If you are ever in the position to defend your actions in court, think carefully before entertaining the thought of a not guilty by reason of insanity plea. While you may be able to make the plea, if it's not legit, you aren't likely to receive any mercy from the court. You can click here for more info on this topic.