Health Mental Illness

Mental Illness

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Mental illness can modify law applications in the case of criminal cases. The presence, nonexistence, or severity of any illness does not by itself make a legal disorder. Meaning that just because an individual has a bipolar disorder, schizophrenia, or even an organic brain syndrome does not necessarily mean that they are insane. The insanity defense is concerned with whether the defendant was legally insane at the time the offense occurred and not his mental state at the time of trial. Therefore, this essay is an illustration on the topic of mental illness in the context of adjudication and sentencing during criminal cases.

Mental illness is inclusive of both mental disorders and intellectual disability. Mental disorder is a syndrome which is characterized by a substantial medical disturbance in a person’s emotions, cognition, behavior, or even regulation. This syndrome leads to the dysfunction of the biological, psychological, or also development process affecting the persons mental functioning. There are several essential considerations concerning mental illness that are to be considered by law reformers. This is that diagnosis in most times is based on the behavioral changes, which include thoughts, feelings, beliefs, perception, and action.

Mental illness defense is also recognized as mental disorder defense. It is a defense mode in a criminal case where the defendants argue to be excused because he or she is not responsible for his or her actions. The defendant argues that he is not responsible for his actions because he was or is suffering from an episode or persistent mental illness during the time the criminal act was committed. In most cases, this argument is followed with a justification of provocation. The defendant is, in most cases, responsible but seeks to lessen his judgment due to brief or persistent mental illness.

There are two standards mostly used during the mental illness argument. These standards include the M’Naghten rule and the second is American legal Institute Model Penal Code Rule (ALI rule). According to the M’Naghten rule, for one to be acquitted not guilty because of insanity during commission of the wrongdoing, one has to be mentally debilitated and should have a flaw of reason or behavior. The reason should be of some mental disorder either a syndrome or defect so severely impact that one does not comprehend the nature and weight of their act. If the defendant understands the nature and weight of the act, they do not understand that what they are doing is wrong. Therefore, it is vital to note that first, the mental status in question should be that of the time the wrongdoing was committed. In case the defendant is fit at the time of trial may be through medication or other reasons, or might be worse and more mentally ill, their status in question should strictly be that of the time when the wrongdoing was committed.

Also, for one to argue mental illness defense in M’Naghten rule, the second criteria illustrate that there has to be a diagnosable disorder that has been diagnosed by a health or psychological professional. Whichever the condition, it should be one recognized by the medical community. The third criteria illustrate that the state has to be so severe that the defendant did not understand what they were doing. Also, if the defendant knew what they were doing, they were not in a place to distinguish right from wrong. Which means that by the prevailing laws and standards of the society, the defendant was not in a position of understanding that committing the crime in question was wrong. However, this does not mean that the offender at the time of the offense thought the act was right. Instead, what it means is that the defendant did not understand that society condemns the act as something wrong. An example is if the defendant committed a crime of stabbing someone to death because he robbed his money. Then the defendant got so angry at them and thought that the victim deserved to die and hence decided to kill him. The criteria illustrate that the defendant did not understand that society condemns the act of stabbing to death as something wrong no matter the situation at hand.

The second standard is the American law institute standard which dates back in the 1960s. It is a bit similar to the white Lynaugh since it illustrates that for the defendant to use mental illness in the context of adjudication or sentencing, first criteria is that they need to have their mental faculties’ impaired at the time of the wrongdoing. Secondly, there should be a diagnosis hence recognized defect. However, the third criteria differ with that of M’Naghten rule since it illustrates that the defendant did not understand the wrongfulness of their actions. However, if the defendant understood what they were doing was wrong, they were unable to control their actions. Meaning that the defendant had no choice or had lost their volition in being able to control their action at the time the crime was committed. Very few psychiatric disorders can cause such level of damage, leading to a person not being able to control themselves.

However, despite all these considerations, it is of utmost importance to get well-detailed information of what happened during the crime. It is therefore essential to talk to witnesses and get the defendants recollection of what happened. It is also necessary to read the arrest report and understand the prosecutor’s motions. All this is essential because in most cases, just because the defendant might be mentally ill at the time of the crime does not necessarily mean they did not know what they were doing. Therefore, it is vital to make a thorough assessment and determine whether mental illness arguments are genuine.

Also, it is also essential to consider any evidence found in the case since there would be evidence that the defendant planned the crime. There would be evidence found that the defendant sought to cover up the crime or evidence that the defendant tried to evade capture from the crime are all vital instruments during the ruling. This evidence can significantly impact the decision made and are, therefore, of high importance. An illustrating example is, a defendant can have bipolar disorder but if he waits for the victim to reach a place for hours then jump on them and kills them, the defendant then tries to dispose of the body, runs away not leaving any evidence. This clearly shows that the defendant knew what he was doing and knew that the act was wrong; otherwise, he would not run away. Therefore it is crucial to separate having mental illness and arguing not guilty by the level of insanity.

In case the defendant successfully argues not guilty based on mental illness, they do not get to walk freely without consequences. Mental illness argument can lead to reduced sentencing in that the defendant serves a considerable term in a protected psychiatric care facility. The defendant is required to receive psychiatric treatment for some time until when they are determined not to be of any threat to society. However, those responsible for this decision highly tend to be cautious, and hence, this can lead to the defendants being institutionalized for more extended periods that they would have served in an ordinary prison.

Due to the rising number of mental health cases, there has been a need for mental health law court as an alternate to navigating the criminal justice system for the people who have mental health disabilities. Mental health law courts were established due to the failure of the traditional law court to tackle a defendant’s possibility of mental disorder in the cases. Since the years 1990s, the number of mental health courts has been increased to cover the high rising cases of defendants suffering from mental disorders trapped in the criminal justice system. However, it is essential to note that mental health courts are a significantly incorrect way of treating homeless persons and also those suffering from mental illnesses whose offense comes from their tough life on the streets. Mental Health America strongly discourages the use of mental health courts to this effect.

Despite the high coverage on mental illness in regards to adjudication in criminal cases, one would think that the defense mechanism is commonly and highly used. However, this is rarely the case. According to , mental illness defense is applied by less than one percent of most court cases. Even when used, the success rate is rated at twenty-six percent. Also, in the twenty-six percent success rate, ninety percent of the defendant are those that have previously been diagnosed with mental illness. Therefore defendants need to be highly cautious when using mental disorder as a defense mechanism.


Following the illustration given, it is clear that each individual has a responsibility to act like an enlightened person and obey the rules and rules in society. If one violates this law and commits a crime, they cannot just argue they had a mental illness because they are suffering from a particular disease and hence are not responsible for the crime. It is, therefore, essential for the defendant to give an apparent reason why they should not be held accountable for the crime committed. The reason is highly important when considering the insanity defense in general. It is also vital to keep in mind that for a defendant to argue mental illness, it does not necessarily mean that in the case of a successful argument, the defendant gets to walk freely. The defendant should understand that this argument can reduce the severity of punishment given or can lead him to serve a given amount of time under secured psychiatric care.


Johnston, E. L. (2017). Mental Health Courts and Sentencing Disparities. University of Florida Levin College of Law, 1-62.

Morse, S. J. (2018). Mental Disorder and Criminal Justice. University of Pennsylvania Law School, 1-79.

Schiffer, M. E. (1976). The Sentencing of Mentally Disordered Offenders. Osgoode Hall Law Journal, 1-39.