Mental retardation and crime

Learning disability is a synonym for mental retardation in the ICD-10 and DSM-IV definitions. This classification is based on the intellectual development quotient (IQ), where the norm is 100.

Mild learning disability is defined in IQ units as 50-70, moderate learning disability - 35-49, severe learning disability - 20-34 and profound learning disability - below 20. The diagnosis is made based on the level of functioning and regardless of the cause of the condition. When using an IQ test, it is necessary to take into account some specific limitations, for example in the area of communication. In addition, the test must be appropriately validated taking into account the ethnocultural background of the person being tested. Mental retardation is acceptable as a diagnosis only if such an inability occurs during the developmental period (up to 18 years).

If there is additional psychiatric disturbance or evidence of physical illness or injury, an additional diagnosis should be made. Mental retardation itself does not imply a lack of ability, nor does it imply that a person is unable to live independently in the community. The closure of chronic hospitals and the development of community care confirm that many people with mild to moderate mental retardation can lead relatively normal lives if they are provided with an appropriate level of support. Another consequence of deinstitutionalization has been that many more people with learning disabilities have come into the attention of the criminal justice system.

[ 1 ], [ 2 ]

Mental retardation and crime

West's research shows that IQ is one of the top five factors associated with the development of delinquent behaviour. People with severe learning disabilities are more likely to be living in residential care settings and are therefore less likely to commit crimes in the community. However, most residential services now operate in a highly integrated community environment and so, depending on the level of supervision in the setting, there are more opportunities for crime than there were previously when most people with such intellectual disabilities were held in NHS hospitals. Hospitals were known for absorbing the criminal behaviour of their residents with minimal police involvement - only for very serious crimes. Modern small residential settings run by social services, voluntary organisations and individuals are more likely to involve the police and seek referrals from local mental health services when crimes occur. However, people are often reluctant to initiate formal legal proceedings if the suspect is a person with severe mental retardation, although legal proceedings are often useful in terms of establishing the facts of the case and determining the structure of any necessary assistance package.

It should be taken into account that not all persons with severe mental retardation can describe their actual actions, and therefore many decisions related to the response to suspected criminal behavior are based on incoherent and unconfirmed information.

It follows that a decision not to hold a trial, although well-intentioned, may in effect deprive a person with a severe mental retardation of the presumption of innocence that underlies the criminal justice system unless proven otherwise. It is for this reason that the Criminal Procedure (Insanity and Incapacity) Act 1991 provides that the facts must first be considered, subject to a "reasonable sufficiency" burden of proof, before any consideration can be given to committing a person who is incapacitated to trial.

Individuals with milder degrees of mental retardation are usually unrestricted in their movements in the community and do so without any supervision, and are therefore more likely to come into contact with the criminal justice system if they commit offences. The full extent of their intellectual disabilities may not be apparent, particularly if poor information processing abilities are masked by a guise of 'social adaptability'. In such cases, it is important to assess the subject's true mental capacity, as this may have implications, in particular, for the credibility of their evidence and their fitness to stand trial. Offenders with mild mental retardation are often able to participate in proceedings and are fit to stand trial, but there is a wide range of sentencing options available, including community or hospital services, as alternatives to criminal sanctions.

Particular problems arise with individuals with an IQ in the range 70-85. This group is usually described as having borderline intelligence. Most are able to live independently, but they suffer from a range of inadequacies and personality problems that may predispose them to antisocial behaviour. They are not covered by the mental impairment provisions of the Mental Health Act, but may be covered by the section on psychopathic disorder. Psychosocial assessment and identification of intellectual deficits can be important in reducing the severity of a sentence and in determining whether it is appropriate.

Studies of populations of children indicate a consistent statistical association between low IQ and criminality. West found that 20% of individuals with IQs below 90 become delinquents, compared with 9% of those with IQs of 91–98 and 2% of those with IQs above 110. On average, delinquents have IQs at least 5 IQ points below the population norm. Studies of prison populations provide wide variations (1–45%) in estimates of the frequency of subnormality, although these may reflect the quality of diagnosis, the characteristics of the prisons studied, the years of assessment, and the quality of the services that may have diverted the learning disabled person from the criminal justice system. The prison data have led to some controversial conclusions about the role of mental retardation in criminality. Although it can be argued that this is because individuals with mental retardation are easier to catch, West’s study and the work of others suggest that individuals with learning disabilities do commit crimes at higher rates. It is noted that in this category of individuals, certain criminogenic factors dominate, such as, for example, a large family, low social status and additional physical limitations, but, as a careful comparison of samples shows, low IQ itself is also a criminogenic factor. Low IQ creates behavioral problems before the age of 3, that is, before the manifestation of learning problems. Poor school performance plus low self-esteem and low frustration tolerance can be combined with certain personality characteristics and the inability to learn from experience, thus forming an increased tendency to antisocial ways of reacting if things do not go as initially expected.

It is generally assumed that individuals with mental retardation, although capable of committing any crime, are most likely to commit sexual offences or arson. This is largely based on clinical practice and research into crimes committed by individuals with learning disabilities who have been institutionalised and should therefore be approached with some caution. However, it is possible that individuals with learning disabilities who come to the attention of forensic psychiatric services will be charged or convicted of these types of crimes. This may be due to the existence of an informal threshold of severity of crimes observed by social and law enforcement agencies when deciding whether to initiate formal proceedings for this category of individuals.

Medical and legal assessment of persons with mental retardation

An appropriate starting point in these circumstances is an assessment of intellectual functioning. Specialists in mental retardation psychiatry are usually able to make a clinical assessment of the case, that is, to determine whether the individual meets the ICD-10 diagnosis of learning disability (mental retardation). Whenever possible, the psychiatrist's assessment should be supported by the results of formal psychometric testing by a clinical psychologist experienced in working with individuals with learning disabilities. In addition to an assessment of intellectual functioning, the possibility of superimposed mental illness, chromosomal or other genetic abnormalities, acquired brain damage, and specific disorders such as autism spectrum disorders should also be considered. It is usually necessary to gather as much background information as possible, and from as reliable sources as possible. In particular, caution should be exercised in assessing the subject's account of the alleged crime. People with intellectual disabilities often take pains not to contradict those in authority and may therefore agree to proposals in conversation without realising the consequences of their responses. To avoid this, the Police and Criminal Evidence Act 1984 requires an appropriate adult to be present when police interview people with learning disabilities or illnesses.

Issues to consider

In assessing a subject accused of committing a crime who is alleged to suffer from mental retardation, the following must be taken into account:

1. Does this subject suffer from a learning disability, and if so, to what extent?
2. Is the subject's behavior truly related to his mental retardation, and does this behavior fall into the category of abnormally aggressive or significantly irresponsible behavior?
3. Is there any reason to suspect that this person has a mental disorder other than a learning disability and, if so, does the presence of such a disorder require specific recommendations?
4. Is the subject capable of participating in the proceedings?
5. Should the question of limited liability be raised in cases of murder?

Assuming that the individual falls within the categories of insanity, severe insanity, mental illness, psychopathic disorder, incompetence or diminished responsibility, the next issue is to recommend to the court where the individual should be placed. If the individual is classified as insanity or as having another mental disorder, the appropriate course of action would be to commit the individual to a hospital under section 37 of the Mental Health Act 1983, which is the best way to meet the individual’s treatment needs. In cases of severe insanity, the treatability requirement that applies to insanity and psychopathic disorder is removed and the option of committing to a specialist institution may then be used as a more humane alternative to imprisonment.

In the vast majority of cases, there is no need to place such persons in hospital. Community sanctions are more appropriate for them. However, the courts must ensure that the measure of placing the person in the community is adequate both from the point of view of therapy and from the point of view of public safety and appropriate prevention of repeated crimes. The following options for community measures are possible:

1. Probation order with condition of compliance with therapeutic regimen.
2. Guardianship order under section 37 of the Mental Health Act 1983.
3. Community supervision orders under the Criminal Procedure (Insanity and Incompetence) Act 1991. These measures allow a comprehensive package of care to be offered and provide a structure to monitor these individuals and control their behaviour. These packages of care usually involve a number of services working together and a specialist who will manage the organisational aspect of this.

Sexual aggression and learning disabilities

Mr. A. (20 years old) is accused of committing the third crime of his life - the attempted rape of a 12-year-old girl. He took her to a field, forced her to undress and was about to rape her, but then passers-by intervened. He was arrested.

His first crime was inappropriately touching a woman in a supermarket, after which he was released on parole. His second crime was grabbing a woman's breasts in the street. His behavior in court left no doubt about the presence of a psychiatric disorder.

A.'s learning difficulties are well documented: he attended a special school. His 1() is 65. He has never held paid employment. He is also known to have a marked deficit in social skills. He is known to have associated with delinquent individuals in his community. There is evidence of alcohol abuse, and alcohol, in the expert's opinion, was largely responsible for his disinhibited behavior. The court accepted a recommendation for psychiatric treatment as a condition of probation. A. attended all scheduled appointments regularly, but it was difficult to engage him in a therapeutic relationship with a treating specialist.

Four months later he was arrested for attempted rape. Further assessment at this stage revealed that he had been fantasizing about pedophilic rape for many years. He admitted to carrying a knife and had fantasies about using the knife during the rape.

The nature of the final offence and the disturbing fantasies left no doubt as to the need to admit A to hospital for further assessment and treatment. Due to the lack of available hospital beds at the time, the decision was taken to admit A to prison but due to his vulnerability in prison, steps were taken to transfer him to a special hospital under section 47 of the Mental Health Act 1983 and with the application of a restraining order under section 49 of the same Act.

He was successfully treated with a therapeutic program of general and sexual education, as well as social skills training and behavioral therapy aimed at counteracting unwanted sexual impulses. At the end of his sentence, the court order under Article 47 was converted to an order under Article 37, without restrictions on movement, and A. was subsequently discharged for further rehabilitation to a regional unit with a high security regime.

Comment

This case illustrates the complexity of attempts to treat people with mental retardation. Ignorance about sexual matters, coupled with poor social skills and the most unimaginable fantasies, can make a mentally retarded person a source of serious danger to society, and therefore it is this aspect that should be a priority when the court decides on the placement of the offender in any of the services.

However, custodial sentences are unlikely to address the underlying cause of the crime in themselves. In this case, the subject, although eventually removed from the criminal justice system, was nonetheless isolated from society for longer than would have been the case had he been incarcerated. On the other hand, the care package and thoughtful rehabilitation provided to him in the special hospital may ultimately lead to a safer and more productive life in the community.

Theft and mental retardation

Mrs B, aged 21, 10, = 67. Referred to a high security unit due to persistent theft, violence against others and self-harm. Attempts to treat and manage her behaviour in the community and at the local assessment and treatment unit have been unsuccessful. B. is admitted to a high security unit under s. 3 of the Mental Health Act on the grounds of mental impairment.

B. has a history of developmental delays dating back to infancy. She was educated in the special education system. Behavioural disturbances were long-standing but became more pronounced after the death of her mother when she was 17. Accordingly, she was diagnosed with abnormal grief disorder and treated for depression. She is described as self-centred, manipulative, has a low tolerance for frustration, impulsive, potentially antisocial and aggressive.

The enhanced supervision conditions involved a behavioral program supervised by a psychologist, in which she gradually learned to take responsibility for her actions. Such programs often cause a temporary exacerbation of undesirable behavior, and then the physical restrictions of the department and the more favorable staff-to-patient ratio make it possible to limit the exacerbation with a reasonable degree of safety.

Comment

This case illustrates how mental retardation can protect the subject from the full rigour of the criminal justice system, in that none of the victims persisted in their charges. The behaviour described above is common to a number of personality disorder syndromes, but in this case it is more accurately attributed to personality immaturity in the context of general developmental delay rather than to personality disorder per se. This case also illustrates the special problems of individuals with mild learning disabilities, related to their lack of ability to function in society at a normal level, given their ability to perceive that they are ‘at a disadvantage’ compared to their peers. Frustration and anger may result, which in an immature personality may lead to serious antisocial behaviour.

Theft and borderline mental retardation

Mr. V. is one of five children in a complete family in which the father suffered from several chronic illnesses, including epilepsy. He had no history of developmental delay, except for nocturnal enuresis, which persisted until age 18. He was classified as a slow learner at school, and completed his schooling at age 15 without any documentation of successful completion. He managed to hold down a job and earn money for four years, but subsequently failed to find another job.

Mr V came to the attention of psychiatrists as a child for learning difficulties and bedwetting. At that time his 10 was assessed as 80. As an adult he was hospitalised for recurrent depression, deliberate self-harm, and a fetishistic fixation with women's underwear. He was also known to be an excessive drinker. His offence was committed in the context of social inadequacy and probable alcohol dependence, and since he did not meet the parameters of mental impairment the court imposed the usual community sanctions on him.

Comment

The 10, 70-85 age group is increasingly supported by specialist community learning disability teams. Although they are not fully considered to have learning disabilities, they do require specialist support skills and the ability to offer treatment, which is available not so much in adult mental health services as in services for the mentally retarded. Despite their obvious subnormality of intelligence, the courts tend to treat them as ordinary defendants unless there are special mitigating circumstances.

[ 3 ], [ 4 ], [ 5 ], [ 6 ]

Violence, depression and mental retardation

Ms. G. is charged with intentionally causing bodily harm: attacking her mother with an element of a decorative garden composition and causing her a serious head injury. At the time of the attack, G. unreasonably believed that she was terminally ill and thought that it was better to "take her mother with her" in this situation.

Her early development was generally normal, except for an overwhelming school phobia. She was considered a failure at school and left school at the age of 15 without any documentation of successful completion. She has never held a steady job. G. was married twice, first to a man 50 years her senior, who died after 10 years of marriage, when G. was 31. She immediately remarried and again to a man 30 years her senior, who died two years later. After the death of her second husband, G. developed severe depression. She also complained of severe abdominal pain for which no organic cause was found. This was the "fatal illness" she spoke of at the time of the crime. Her descriptions of this illness became increasingly bizarre, and she was diagnosed with major depressive disorder with marked nihilistic delusions. On subsequent examination she was found to have a score of 10, equal to 69. She was admitted to hospital under section 37 of the Mental Health Act 1983 on the grounds of mental illness, where she was treated quite successfully for her illness.

Comment

This case illustrates well the comorbidity that is often found in criminals with learning disabilities. G. undoubtedly has a learning disability, but at the same time her behavior is more a consequence of her illness than of arrested or incomplete intellectual development.

Treatment of criminals with mental retardation

Community Services

Most often, individuals with learning disabilities who have committed crimes or exhibit severe challenging behaviour are referred for treatment to community services.

The law provides for the following possibilities:

• probation order with treatment condition;
• supervision under the Criminal Procedure (Insanity and Incompetence) Act 1991;
• guardianship under section 37 of the Mental Health Act 1983;
• guardianship under section 7 of the Mental Health Act 1983.

Regardless of the options provided by law, these individuals are offered a comprehensive assistance package, which includes the following elements:

• placement with a family or placement in public, voluntary or independent service;
• provision of educational programs;
• structured daytime employment;
• therapeutic interventions from the National Health Service, social services and/or probation services;
• condition monitoring;
• coordination of the aid package and monitoring its implementation.

The key element is usually the involvement of a specialist in mental retardation psychiatry and the availability of an adequate support team in the community.

[ 7 ]

Local inpatient services

In cases where a community program is not well suited to the individual or where further assessment is required, local inpatient units provide structured intervention settings.

Admission to these units for high security purposes is made under s.3 or 37 of the Mental Health Act 1983. Where a s.37 order is made, a s.41 Restraining Order may be made in addition. With most hospitals closed to accommodate people with mental disabilities, local inpatient services are not so much places of long-term detention as a support element to existing community services. Accordingly, they are used for assessment and attempted therapeutic interventions to develop a community-based programme of care. In particular, they may be useful in providing a structured environment in the early stages of behaviour change programmes.

High security departments

Most general high-security units accommodate only those with the mildest forms of intellectual disability. The need for specialist services at this level of security was reflected in the Oxford Inquiry and in recent years a number of such units have been commissioned both within the NHS and in the private sector. The main reason for admitting people to these units is that local services are unable to cope with their behaviour in their own security environment. Newly established high-security services are already developing specific expertise in the treatment of sex offenders and are able to offer a level of security and potential length of stay that local services cannot provide.

[ 8 ], [ 9 ]

Special hospitals

Rampton and Ashworth Hospitals currently provide facilities for the mentally retarded. However, reviews of these services have been mixed, and there is growing concern that many mentally retarded patients admitted to these hospitals do not require such strict security conditions.

It is possible that further study of the performance of special hospitals in relation to all types of patients will eventually lead to the construction of small targeted units for people with learning disabilities who pose a serious and immediate danger to others.

Prison Service

Although a significant proportion of people with mental retardation who commit crimes are still imprisoned, the prison service has no special provision for this very vulnerable group of prisoners. It is hoped that improved pre-trial psychiatric assessment, coupled with the safeguards of the Police and Criminal Evidence Act 1984, will help to reduce the number of unnecessary detentions of this group of offenders.

Mental Retardation and Mental Health Act 1983

Society has traditionally protected individuals with learning disabilities from the strict application of the law, and has allowed intellectual disability to be taken into account as a mitigating factor and, if severe enough, as grounds for finding a person not guilty by reason of insanity. Although some individuals with milder degrees of mental retardation can and do adapt to prison, it is clearly inappropriate to impose ordinary criminal penalties on individuals with more severe degrees of intellectual disability. In addition, it is also generally accepted that learning disability itself is not a reason for institutionalization unless it improves the individual's situation. Parker found that more than half of the individuals classified as subnormal actually had IQs above the level at which they were classified. There is a tendency to base intellectual functioning on the individual's social functioning rather than on the more precise criteria of international classification systems.

The Mental Health Act 1983 introduced new terms, including mental impairment and severe mental impairment, to narrow the scope of the Act to apply only to people with learning disabilities for whom admission to hospital is necessary for the treatment or protection of themselves or others, and where their placement in a custodial institution is not a realistic alternative.

Mental disability is defined as a state of arrested or incomplete development of a person's mind (short of severe mental disability), which includes significantly reduced levels of intelligence and social functioning and is associated with abnormally aggressive or significantly irresponsible behavior. Severe mental disability is defined as a state of arrested or incomplete development of a person's mind, which includes severe levels of reduced intelligence and social functioning and is associated with abnormally aggressive or significantly irresponsible behavior. Definitions of "severe" and "significant" are not given, but it is generally accepted to use IQ levels of 60-70 and, accordingly, below 60. The definition of severe mental disability is sufficient to recommend to the court that the person be hospitalized. However, in the case of "mental disability", hospitalization for the purpose of treatment must improve the person's situation or prevent his or her condition from worsening.

Of course, if a criminal with mental retardation also suffers from a mental illness, then such an illness may be the basis for a psychiatric recommendation for forced placement in a hospital.