Sample Essay on The Hinkley Verdict and the Insanity Defense

The Insanity Defense


The insanity defense is an argument in a criminal case arguing that the defendant is and was mentally challenged at the time he/she committed a crime and should therefore not be held accountable for the crime committed since he/she was not in a position to control his/her actions at the time. The defense is based on the theory that though most people are able to adhere to the rule of law by being able to control their feelings and actions, some people are unable to follow the rule of law owing to mental incapacitation which hinders their ability to make sound judgement thus depriving them of the innate ability to act rationally. The insanity defense dates back to the 1843 where it was first referred to as the M’Naughten rule. This was after the assassination attempt on the then British Prime Minister Robert Peel and the murder of his assistant by an individual named David M’Naughten who thought he was being persecuted. The defendant pleaded insanity at the trial and the prosecution’s attempt to prove the defendant’s sanity by revealing his planning and premeditation in the attack failed since he was declared insane and psychotic. The M’Naughten rule stated that one was found to be insane if he did not understand the grievous nature of the act he was committing and if he knew, then he did not understand that what he was doing was wrong (Jacewicz, 2016).

However, the 1982 verdict of President Ronald Reagan’s assassin John Hinkley sparked outrage and pressures from the public so much so that the congress and some states were forced to make changes to the insanity defense. At the time, Hinkley who was obsessed with the actress Jodie Foster from the movie Taxi Driver in which the main actor plots to assassinate the president was found to be a troubled man diagnosed with extreme mental disorder and schizophrenia was found not guilty by reason of insanity (“NGRI”) and could therefore not be held accountable for his actions. At the time, persons acquitted by the use of the ‘not guilty by reason of insanity’ rule would be committed to institutions for the criminally insane for many years or even a lifetime. This was a sympathetic way of showing that it would be utterly unfair to punish someone who had no consciousness of his actions and furthermore, it was an assurance to the public’s safety that such a person would be locked in a correctional facility rather than be allowed to freely roam the streets according to Collins et al (2016). However, after the Hinkley verdict, the public outrage prompted the congress and the states to make necessary changes to the insanity rule with some states abolishing it entirely.

History of the Insanity Defense in the US.

The Right/Wrong M’Naughten Rule.

David M’Naghten was a delusional man who attempted to assassinate the then British Prime Minister sir Robert Peel but ended up mistakenly shooting his assistant due to his delusions that made him believe that he was being persecuted. M’Naghten was however acquitted through the “not guilty by reason of insanity” verdict after medical evidence showed that he was not culpable of such a crime due to his mental insanity. The queen and the public however disagreed with the verdict and the House of Lords reviewed and reversed the verdict then came up with the M’Naghten rule which stated that a person should not be held accountable for his actions in the event that he was unaware that he was doing something wrong while committing the crime. Which in essence is the inability to differentiate between right and wrong due to a mental incapacitation. The M’Naghten rule however came under criticism due to its inability to prove whether or not the offender knew he was doing wrong but was unable to control his actions. Hence, it was felt to be too rigid and as a result, the irresistible impulse effect was adopted in the US.

The Irresistible Impulse Effect

The irresistible impulse effect was adopted due to failure of the M’Naghten rule to put the issue of control into perspective and only dwelt on the cognitive perspective of the insanity defense. The irresistible impulse effect was based on the volition and control theory which insinuated that some offenders would be able to know what they were doing was criminal but would be unable to control their actions nonetheless because of insanity. However, this test was criticized for being too easy with arguments that most people suffer from impulses but learn to control them hence, it would be wrong not to punish offenders using this argument and it would be quite a challenge to establish whether or not a defendant merely chose to not control his/her action while conducting the crime according to Rolf (2006). An argument that is supported by the American Psychological Association (APA: The Insanity Defense Position Statement). The Irresistible Impulse Effect is still used in Virginia today in its original form and was applied recently in the Virginia case of Lorena Bobbitt who was charged with wounding by cutting his husband’s penis off while he was sleeping. The defense however argued that though Lorena knew that cutting off her husband’s penis was an offense; she could not control herself because of a mental disorder she was suffering from referred to as the bartered-wife syndrome.

The Durham Test

Following the failure of the M’Naghten rule and the Irresistible Impulse Effect, the Durham test was adopted which was believed to be more effective since it leaned more toward a scientific explanation as opposed to the cognitive, volition and control perspectives. The Durham test stipulated that no one should be held accountable for a criminal behavior in the event that his actions were prompted by a mental disorder or disease because in so doing, it would be equated to punishing the individual for the disease. The Durham test would only be viable when a defendant was able to prove his mental incapacitation at the time the crime was committed which would be proved by medical experts’ testimonies and that the defendant did not have the Mens rea to commit the crime since criminal act was as a result of the mental disease. The test proved to be challenging in its application and was criticized for using the scientific argument. The test was too broad and it was feared that it would be used to acquit too many people since it had given psychiatrists a lot of influence in the courtrooms (Danita, 2002). The test was also criticized because it would be very difficult to prove that a mental disorder was the cause of a criminal behavior especially due to the fact that there are diverse natures of mental defects and for the fact that there is no clear definition of mental disorder. For these reasons, the test was considered to be vague, was eventually rejected in the US and in 1972, federal judges overturned the ruling in favor of the Model Penal Code test of the American Law Institute (ALI).

The ALI Substantial Capacity.

The American Law Institute (ALI) came up with a different definition of insanity. The ALI combined both the M’Naghten right and wrong rule and the Irresistible Impulse test. The ALI was considered to be a softer version of the M’Naghten rule and was immediately adopted by state and federal jurisdictions who faulted the M’Naghten rule. According to Rolf (2006), the aim of the ALI was to show that although a defendant under the substantial capacity test had knowledge that what he was doing was a crime, he could still be found not guilty by reason of insanity in that despite being aware of his actions, he lacked the substantial capacity to acknowledge the nature and level of his actions and conform as per the recommendations of the law. The ALI incorporated the Mens rea to examine the levels of insanity in a defendant. According to the ALI Model Penal Code (ALI Model Penal Code, 1985), a person would not be held accountable for criminal behavior if at the time of the criminal act he lacked the substantial capacity to either acknowledge the criminality of his actions or conform to the requirements of the law. The ALI came up with more strict rules governing it which involved having certain mental defects held accountable for their actions with the argument that some mental cases were still conscious enough to cloud their judgements at the time of conducting the crime. More than 20 states adopted the ALI substantial capacity test and some are still using the test to date although they made reforms to the test after the Hinkley verdict. An ALI substantial capacity test would only be effective when an offender was suffering from a mental disease based on the testimonies of medical experts and during the time the criminal act was conducted, the defendant lacked the substantial capacity to recognize the effects of his actions and is unable to control his actions to a morally accepted standard. Critics of the ALI test attack it on grounds that it lacks guidance and directions to the jurors. It is faulted since it fails to fully define what percentage constitutes lack of substantial capacity thus arguments that a defendant with a 25% lack of capacity might be acquitted by the jury yet he is in fact guilty and was aware of his criminal action. The substantial capacity is still used in several states to date. A case in point is the Jeffrey Dahmer case of the murder of 17 young men and cannibalism. Although the defense used the substantial capacity argument, the prosecution was able to convince the jury that the defendant was quite aware of his actions.

The Federal Insanity Defense Act Of 1984

Shortly after the Hinkley verdict, the congress and several states put stricter rules on the insanity plea. For instance, The Federal Insanity Defense Act of 1984 was among the first legislative acts that gave a new outlook on the insanity defense. The act brought up new stricter measures on the insanity plea that was previously presented in federal courts. The act put a burden on the defendant to fully provide convincing evidence that he is mentally incapacitated as opposed to prior to the Hinkley burden where the burden was on the prosecution to prove that the accused was sane at the time he committed the crime failure to which the argument would not hold up in court. In addition, the act provided for federal commitment of persons that became insane while serving a prison sentence or after being found guilty. This meant that the act eliminated the Irresistible Impulse Test which basically failed to distinguish which acts were impossible to control from those that were merely uncontrolled. The Irresistible Impulse Test had also been scrutinized in several states for being too broad in its definition of insanity. The test had to prove that the defendant was insane and that his mental incapacitation deprived him of the ability to control his actions while committing the crime which was quite challenging to prove.  The act also abolished the defense of diminished capacity which in essence meant that the insanity plea by the defendant would not negate the fact that he had committed the crime and would therefore be held accountable for his actions.

Modification of the Standard for Insanity

Another basic premise of the Federal Defense Act of 1984 is the modification of the standards for insanity that had been previously used in court. Prior to the Hinkley verdict, a defendant would be declared not guilty by reason of insanity but after the public out roar following the Hinkley trial, several modifications were made to the “not guilty by reason of insanity” verdict as discussed below.


Limiting the Use of Expert Witness

 With the modifications of the definition of insanity the reform act further limited the scope of expert testimonials in such cases that involved the insanity defense. This is because of the abolition of the cognitive and volitional “scientific” approach to allow the use of cognitive “moral” definition which was arguably more effective. This meant that psychiatrists and other professional eye witnesses would not voice their expert opinion on the sanity or absence thereof in a defendant. According to Richard J. Bonnie a Professor of Law and Director of the Institute of Law, Psychiatry and Public Policy at the University of Michigan, there is no definite measure of a person’s capacity for self-control except by making a moral guess. Therefore, the function of psychiatrists is not fundamental in criminal cases.  They would only be allowed to describe the condition as per their professional observation but the decision to determine whether the defendant is mentally incapacitated or not would be entirely left for the jury to decide. This was aimed at reducing the influence of psychology in the courtroom as had been the case with the Durham test. A time frame was set up for those that were committed to mental institutions as opposed to prior to the Hinkley verdict where those committed to mental institutions would last long years with some spending a lifetime in those institutions. However, several states came up with review boards that were meant to monitor a person’s progress in the mental institutions, oversee their treatment, set conditions that were to be met for a person to be released from the institutions and also took custody of those committed (Ball, 2005). The Hinkley verdict also facilitated the adoption of the “guilty but mentally ill” verdicts by states such as Michigan. This meant that although the defendant would be mentally ill, he would still be found guilty of the committed crime. The act gave provisions for those found guilty but mentally ill to receive psychiatric treatment while being locked up or be placed in mental institutions until such a time when they would be well enough to be moved to a prison and fully serve their sentence.

The Complete Elimination of the Insanity Defense.

However, in some instances, the insanity defense was completely eliminated in the wake of the Hinkley verdict. For instance, the insanity plea in 1995 employed by Francisco Martin Duran on his assassination attempt on the then President Bill Clinton’s life was rejected and he was found guilty of the charges that had been levelled against him. According to Rolf (2006) several states amongst them Idaho, Utah and Kansas abolished the insanity defense entirely in the following statutes:

“Mental condition shall not be a defense to any charge of criminal conduct”

“It is a defense to a prosecution under any statute that the defendant, as a result of mental disease or defect, lacked the mental state required as an element of the offense charged. Mental disease or defect is not otherwise a defense”

“(1)(a) It is a defense to a prosecution under any statute or ordinance that the defendant, as a result of mental illness, lacked the mental state required as an element of the offense charged.

California followed the abolition of the insanity plea although the M’Naughten rule was still permissible but had the following provision under the California Penal Code 25(a) (Rolf, 2006):

“The defense of diminished capacity is hereby abolished. In a criminal action, as well as any

Juvenile court proceeding, evidence concerning an accused person’s intoxication, trauma, mental illness, disease, or defect shall not be admissible to show or negate capacity to form the particular purpose, intent, motive, malice aforethought, knowledge, or other mental state required for the commission of the crime charged”

The Guilty but Mentally Ill Verdict

The “guilty but mentally ill” verdict is considered to be one of the greatest reforms following the Hinkley verdict. The verdict was adopted by over 20 states for instance, in 1984 South Carolina adopted the verdict whose provisions dictated that a defendant was guilty but mentally ill if he was in a position to differentiate between what is regarded as moral/legal right to the moral/legal wrong but due to his mental incapacitation, he was unable to control his actions as per the requirements of the law. The verdict aims at protecting the rights of the mentally ill in order to have them receive treatment while at the same time punishing wrong doers irrespective of their mental abilities in order to curb crime. The verdict stipulates that although a defendant may be found guilty, he could still be mentally ill and would therefore be required to be placed under treatment. A case in point is the 1997 Pennsylvania conviction of John Du Pont who was found “guilty but mentally ill” after shooting and killing former gold medalist David Schultz after having severe delusions (Rolf, 2006). However, under this verdict, the defendant is only found to be “guilty but mentally ill” in the event that the prosecution proves beyond reasonable doubt that the defendant committed the crime, the defendant is unable to provide clear and convincing evidence that he is mentally incapacitated (burden of proof) and in the absence of sufficient medical opinion usually from medical experts that show that the defendant is mentally challenged. The sentencing of defendants under the “guilty but mentally ill” verdict would be to the prison but such a person would receive treatment first until such a time when they would be considered sane and not pose a threat to their safety and the safety of their fellow inmates. The 2002 Texas Andrea Yates case is an example of how the insanity defense plea has evolved over the years since the Hinkley verdict. Although she pleaded not guilty by reason of insanity in the murder by drowning of her children in a bathtub, the jury determined that she was not legally insane due to the evidence of her phone call to the police confessing what she had done. She was sentenced to life imprisonment while still awaiting her appeal. However, the adoption of the “guilty but mentally ill” verdict has raised concerns over the years on its effectiveness. For instance, a report from the department of justice in 1999 (Rolf, 2006) estimated that of the 16% of the incarcerated persons with mental disabilities, only about 60% of them have access to treatment for their mental disorders thus raising concerns that some of them could be released to the public with little or no change in their mental status hence posing a threat to the society and to themselves. Steadman (1993) conducted a study that showed that only 3 out of 150 defendants incarcerated through the “guilty but mentally ill” verdict had access to treatment which raises questions as to the effectiveness of the verdict in reforming the offenders.

Temporary Insanity

Prior to the Hinkley verdict, defendants who would take the temporary insanity defense would argue that they were medically insane at the time of the crime but were no longer insane and would be acquitted through the not guilty by reason of insanity verdict and would therefore not be committed to mental institutions since the insanity was only for a while. After the Hinkley verdict however, such pleas were abolished due to the need to punish the offenders and deter would be offenders from using such pleas as their defense.   In Missouri, however, several provisions have been stipulated for cases of temporary insanity which state that in the event that the accused is able to successfully prove temporary insanity, it is up to the jury to determine whether or not the accused’s reasoning capacity has been restored to considerably normal levels and whether or not he/she is safe to the public. The Missouri provisions also stipulate that any defendant acquitted on the grounds of temporary insanity is committed to the director of the mental health department after which the court shall order custody in a retardation facility unless an immediate release is granted (Miss.code, 2005)

The Burden of Proof

Prior to the Hinkley verdict, the law required the prosecution to prove that the defendant applying the insanity plea defense was actually medically sane at the time of the crime and could distinguish right from wrong. This however changed after the Hinkley trial. The burden of proof shifted and it was required that the defendant provide undisputed evidence that he/she was insane when committing the crime which would either mean that the defendant had no knowledge of the nature of his /her action and in the event that he/she was aware, the mental incapacitation hindered  control over his/her actions. Under the reformed act, the defense would be required to provide clear convincing evidence that the defendant was mentally ill and not just suffering from a personality disorder (Gina, 2005) and the court would hold the defense with higher expectations in the provision of the evidence. Several states quickly adopted the burden of proof shift after the Hinkley verdict with Arizona, Connecticut and Texas making changes to it.

The Burden of Persuasion

While both the federal and state courts have agreed to put the burden of proof on the defendant, there have been differing views as to who should bear the burden of persuasion over the years. After the defendant has provided reasonable doubt to his sanity at the time of conducting the crime, the question as to who should bear the burden of persuasion arises. Prior to the Hinkley verdict, the burden was entirely for the prosecution but after the modifications to the definition of insanity, several options for the bearer of the burden of persuasion have been produced. For instance, several states put the burden of persuasion on the prosecution. In such cases, once the defendant produces evidence that puts considerable doubt on his action at the time of the crime, the prosecution is then required to provide sufficient evidence to the contrary failure to which the defendant will be acquitted (Rolf, 2006). Other jurisdictions however place the burden on the jury even in cases where the prosecution has not offered evidence of sanity.  Ball (2005) argues that the latter form of placement of burden of persuasion is better than the former due to the fact that a defendant may not have the financial ability to fund an insanity defense while the state has more than enough funds at its disposal in which case a defendant might be sentenced for his inability to prove insanity due to lack of funds.

Some jurisdictions however place the burden of persuasion on the defendant who aside from providing clear evidence of his mental defect at the time of the crime, he is also required to successfully persuade the jury in order to be acquitted. This, in researchers’ view is the best type of jurisdiction in that a defendant would have to labor more into persuading the court of his insanity rather than merely come up with an insanity evidence. Congress also lays the burden of persuasion on the defendant but puts on stricter measures on the provision of evidence of insanity under which the defendant is to be exonerated.


In conclusion, the Hinkley verdict facilitated the much-needed reforms and evolution of the insanity defense. As a result, the changes made to the defense would deter the acquittal of actual criminals hiding behind the insanity defense and offer treatment to those found guilty under the reformed insanity defense. Stricter measures that have been included in the insanity defense helps to reduce the number of insanity pleas and although there are still lingering questions on the effectiveness of the insanity defense even after the reforms, there is hope that the chances of persons getting acquittals merely by employing the “not guilty by reason of insanity” rule are getting slimmer with the adoption of such verdicts as the “guilty but mentally insane” verdict and by the abolition of the diminishing capacity defense. In addition, the adoption of measures like the burden of proof shift and burden of persuasion which put pressure on the defense to prove their alleged mental incapacity at the time of conducting the crime to show they were either unaware of their criminal actions or if they were aware of their action, the mental defect deterred them from controlling themselves in conformity to the law are considered to be a big step as opposed to before the Hinkley verdict where an expert opinion would be highly considered in the insanity defense. The limiting of the influence of psychiatrist and science in criminal cases involving the insanity defense is another basic premise of the reformed insanity defense that was aimed at restricting the insanity defense plea.

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