Forensic Forensic Psychiatry of Psychiatry of Intellectual Intellectual disabilitydisability

Dr M A RazzaqueDr M A RazzaqueMBBS DFSRH FRSPH DPM FRCPsychMBBS DFSRH FRSPH DPM FRCPsych

Rtd. Medical Director / Consultant Rtd. Medical Director / Consultant PsychiatristPsychiatrist

Relationship of Mental Relationship of Mental Retardation to CrimeRetardation to Crime

Distribution of intelligence score in the Distribution of intelligence score in the criminal population was similar to that in criminal population was similar to that in the general populationthe general population

IQ for sex offenders was significantly lower IQ for sex offenders was significantly lower than that of other offenders (East, 1942)than that of other offenders (East, 1942)

Suggested intelligence was a factor in Suggested intelligence was a factor in determining types of crime (Foxn USA, determining types of crime (Foxn USA, 1946) – 1946) –

High intelligence was related to crimes of High intelligence was related to crimes of forgeryforgery

Low intelligence was related to sex Low intelligence was related to sex offending and vagrancyoffending and vagrancy

continuedcontinued

Delinquency was principally a problem Delinquency was principally a problem of mild mental retardation (Ferguson, of mild mental retardation (Ferguson, 1952)1952)

Retarded youngsters tended to be Retarded youngsters tended to be convicted for first offences at a convicted for first offences at a relatively earlier age and to be relatively earlier age and to be convicted more frequently and to have convicted more frequently and to have a greater number of convictions than a greater number of convictions than ordinary youngstersordinary youngsters

continuedcontinued Walker and McComb (1973) found one third Walker and McComb (1973) found one third

of males identified as ‘mentally retarded’ of males identified as ‘mentally retarded’ were sex offenders – victims were childrenwere sex offenders – victims were children

‘‘Mentally impaired’ female sex offenders Mentally impaired’ female sex offenders tended to be involved in soliciting, tended to be involved in soliciting, prostitution or incest – they became victims prostitution or incest – they became victims as much as offendersas much as offenders

Association between arson and mental Association between arson and mental retardation was confined to fire-setting retardation was confined to fire-setting behaviourbehaviour

General CharacteristicsGeneral Characteristics

-As in the general population, intellectual disability -As in the general population, intellectual disability offenders are essentially a male phenomenaoffenders are essentially a male phenomena

-Typical the male offender with intellectual -Typical the male offender with intellectual disability is functioning in mild borderline disability is functioning in mild borderline intellectual rangeintellectual range

-Is in the early 20’s-Is in the early 20’s -From poor urban environment-From poor urban environment -Has suffered an unsettled and deprived -Has suffered an unsettled and deprived

upbringingupbringing -Is likely to have a history of behavioural disorders-Is likely to have a history of behavioural disorders

General Characteristics General Characteristics continuedcontinued

History of previous convictionsHistory of previous convictions Residential placementResidential placement Shown evidence of psychiatric disturbance and Shown evidence of psychiatric disturbance and

personality disorderpersonality disorder They share many features in common with non-LD They share many features in common with non-LD

offendersoffenders Robertson, 1981, has pointed out that they Robertson, 1981, has pointed out that they

differed significantly from mentally ill offenders differed significantly from mentally ill offenders whose criminal behaviour is in the main, whose criminal behaviour is in the main, secondary to psychiatric disordersecondary to psychiatric disorder

General Characteristics- General Characteristics- continuedcontinued

Mentally ill offenders were found toMentally ill offenders were found to be: be:

-Older at first conviction-Older at first conviction

-Had more admissions to psychiatric -Had more admissions to psychiatric hospitalshospitals

- Showed a high frequency of violence- Showed a high frequency of violence

- Tended to be detained for shorter periods- Tended to be detained for shorter periods

- Committed fewer serious offences during - Committed fewer serious offences during the follow-up periodthe follow-up period

-The pattern for offending in patients -The pattern for offending in patients with intellectual disability shows with intellectual disability shows considerable differences from that of considerable differences from that of the general populationthe general population

Patterns of offending behaviour

Whilst property offences are the Whilst property offences are the commonest offences in both groups – sex commonest offences in both groups – sex offences and arson are over represented offences and arson are over represented in patients with intellectual disabilityin patients with intellectual disability

Crimes involving serious personal Crimes involving serious personal violence, including murder, are under violence, including murder, are under representedrepresented

Recidivism, or relapse is common in Recidivism, or relapse is common in offenders who have intellectual disabilityoffenders who have intellectual disability

continuedcontinued

Offending in patients with Offending in patients with intellectual disability is nearly intellectual disability is nearly always the consequence of impaired always the consequence of impaired self-control, under socialisation and self-control, under socialisation and faulty social learningfaulty social learning

Aetiology

-Impaired cognitive functioning means -Impaired cognitive functioning means the individual is intellectually less the individual is intellectually less capable of reasoning out the capable of reasoning out the consequences of his or her actionsconsequences of his or her actions

- less well equipped to resist temptation- less well equipped to resist temptation

-more easily led into offending by others -more easily led into offending by others

Cognitive functioning and personality

Cognitive functioning and Cognitive functioning and personality continuedpersonality continued

-Impulsivity and gullibility are the -Impulsivity and gullibility are the hallmarks of offending in people hallmarks of offending in people with intellectual disabilitywith intellectual disability

- Joint offences often with intelligent - Joint offences often with intelligent superiors are commonsuperiors are common

- Patients with severe Mental - Patients with severe Mental Retardation are often unable to Retardation are often unable to comprehend that their behaviour is comprehend that their behaviour is legally wronglegally wrong

Brain damage and cerebral Brain damage and cerebral abnormalityabnormality

The association between criminal The association between criminal behaviour with cerebral abnormality behaviour with cerebral abnormality and epilepsy has long been establishedand epilepsy has long been established

High incidence of EEG abnormalities High incidence of EEG abnormalities found in unstable and violent offendersfound in unstable and violent offenders

The number of confirmed epileptics in The number of confirmed epileptics in the prison population is significantly the prison population is significantly greater than in the general populationgreater than in the general population

ContinuedContinued Studies have demonstrated the association Studies have demonstrated the association

between prematurity and birth complications between prematurity and birth complications and subsequent anti-social behaviourand subsequent anti-social behaviour

Anti-social behaviour of personality change Anti-social behaviour of personality change following head injuryfollowing head injury

Damage to the frontal lobe and limbic system Damage to the frontal lobe and limbic system resulting in social disinhibited behaviour and resulting in social disinhibited behaviour and sometimes offending in a previously law-sometimes offending in a previously law-abiding personabiding person

Reduced frustration, tolerance and increased Reduced frustration, tolerance and increased irritability with excessive and often explosive irritability with excessive and often explosive response to trivial provocationresponse to trivial provocation

Sex chromosome abnormalitySex chromosome abnormality

The association between additional sex The association between additional sex chromosomes, intellectual impairment chromosomes, intellectual impairment and a tendency towards criminality is well and a tendency towards criminality is well knownknown

42% XYY group and 19% XXY men found 42% XYY group and 19% XXY men found convicted as compared to 9% the normal convicted as compared to 9% the normal populationpopulation

The nature of the association is poorly The nature of the association is poorly understood and many XYY individuals live understood and many XYY individuals live perfectly blameless within the communityperfectly blameless within the community

Physical and mental healthPhysical and mental health

Higher than normal prevalence of Higher than normal prevalence of minor auditory and visual defects minor auditory and visual defects have been found in studies of people have been found in studies of people with intellectual disabilitywith intellectual disability

Although minor in themselves, they Although minor in themselves, they are thought to contribute to the are thought to contribute to the alienation of individuals from societyalienation of individuals from society

Impede the process of socialisation Impede the process of socialisation and social learningand social learning

Physical and mental healthPhysical and mental health

Give rise to feelings of inferiority which Give rise to feelings of inferiority which may be compensated by anti-social may be compensated by anti-social behaviourbehaviour

Minor speech defects such as slowness Minor speech defects such as slowness and poor articulation could provide and poor articulation could provide further barriers to socialisationfurther barriers to socialisation

There is evidence that correction of minor There is evidence that correction of minor facial abnormality by cosmetic surgery facial abnormality by cosmetic surgery reduces criminal behaviour in delinquentsreduces criminal behaviour in delinquents

Psychosocial FactorsPsychosocial Factors Low social economic classLow social economic class High incidences of neighbourhood crimeHigh incidences of neighbourhood crime Broken homesBroken homes Chronic unemploymentChronic unemployment PovertyPoverty Urban settingsUrban settings Faulty child rearing practiceFaulty child rearing practice Family history of criminality and associated Family history of criminality and associated

with delinquency and criminal behaviour in with delinquency and criminal behaviour in general and is also seen in intellectual general and is also seen in intellectual disability offendersdisability offenders

Psychodynamic factorsPsychodynamic factors

Psychological mechanism frequently plays an Psychological mechanism frequently plays an important role in their offending behaviourimportant role in their offending behaviour

Delinquent behaviour is often motivated by Delinquent behaviour is often motivated by status seekingstatus seeking

The learning disabled youth, achieving The learning disabled youth, achieving acceptance with his peer group membership acceptance with his peer group membership of the gang, and sometimes high status of the gang, and sometimes high status which he could never otherwise hope for by which he could never otherwise hope for by participating in offending and daring participating in offending and daring escapadesescapades

Psychodynamic factorsPsychodynamic factors

Difficulty in establishing satisfactory Difficulty in establishing satisfactory relationships with the opposite sex, relationships with the opposite sex, coupled with poor impulse control and coupled with poor impulse control and courtship techniquescourtship techniques

Communication difficulties may lead to Communication difficulties may lead to the misinterpretation of harmless the misinterpretation of harmless intentions with criminal acts as a possible intentions with criminal acts as a possible consequencesconsequences

Loss of caring relatives or moving to a less Loss of caring relatives or moving to a less structured setting can result in offendingstructured setting can result in offending

PresentationsPresentations

Theft, robbery, burglary and acts of Theft, robbery, burglary and acts of vandalism are the commonest formvandalism are the commonest form

There is frequently an opportunist, There is frequently an opportunist, unplanned component to the offences with unplanned component to the offences with lack of sensible precautionslack of sensible precautions

Thoughtless and sometimes an excitement Thoughtless and sometimes an excitement factorfactor

The chances of getting caught are high The chances of getting caught are high because of the general lack of awareness because of the general lack of awareness and ineptitude once it comes to escaping or and ineptitude once it comes to escaping or concealing tracksconcealing tracks

The majority of offences are committed The majority of offences are committed jointly, usually with more intelligent peersjointly, usually with more intelligent peers

Gaining acceptance within the group may Gaining acceptance within the group may be the motivating factorbe the motivating factor

Solitary delinquent acts are less common Solitary delinquent acts are less common and usually result from the inability to and usually result from the inability to control an overwhelming desire or an over control an overwhelming desire or an over reaction to frustrations in a reaction to frustrations in a temperamentally predisposed individualtemperamentally predisposed individual

Sex offendersSex offenders

majority of incidents are of a minor majority of incidents are of a minor nature, mainly incidents of exposure nature, mainly incidents of exposure and minor indecent assaultand minor indecent assault

due to the consequences of normal due to the consequences of normal sex drive coupled with lack of sex drive coupled with lack of opportunities for normal sexual opportunities for normal sexual outlets compounded by poor impulse outlets compounded by poor impulse control, lack of social skills and control, lack of social skills and protective and restrictive familiesprotective and restrictive families

Sex offenders- continuedSex offenders- continued

Persistent and more serious offenders, on Persistent and more serious offenders, on the other hand, tend to come from highly the other hand, tend to come from highly disturbed family backgrounds, show disturbed family backgrounds, show evidence of personality disorder and evidence of personality disorder and commit ranges of other offencescommit ranges of other offences

Sex is entirely a matter of personal Sex is entirely a matter of personal gratification to themgratification to them

Are indiscriminate in their choice of Are indiscriminate in their choice of victim and frequently use violencevictim and frequently use violence

Sex offenders -continuedSex offenders -continued

Indecent exposure is typically carried out Indecent exposure is typically carried out impulsively without precautions to escape impulsively without precautions to escape detection – frequently from window or door detection – frequently from window or door of the family home or in the street or local of the family home or in the street or local parks. The incidents of indecent exposure parks. The incidents of indecent exposure are equally impulsive and are rarely are equally impulsive and are rarely harmful to the victimharmful to the victim

Misinterpretation of the friendliness shown Misinterpretation of the friendliness shown by female staff, neighbours or female by female staff, neighbours or female friends sometimes result in inappropriate friends sometimes result in inappropriate sexual advances sexual advances

Sex offenders -continuedSex offenders -continued

Failure to recognise differences in Failure to recognise differences in relationships between people can relationships between people can also occuralso occur

A high percentage of the victims are A high percentage of the victims are children and usually below the age children and usually below the age of 14 yearsof 14 years

ArsonArson Although fire setting may be committed by Although fire setting may be committed by

individuals at all intellectual levels, most individuals at all intellectual levels, most studies show it to be particularly associated studies show it to be particularly associated with low intelligence and mental retardationwith low intelligence and mental retardation

Mainly 16-25 age groupMainly 16-25 age group High incidents of attempted suicide, self High incidents of attempted suicide, self

mutilation, psychotic overlay and property mutilation, psychotic overlay and property offencesoffences

Much lower incidents of aggression towards Much lower incidents of aggression towards others and sex offences, compared to the others and sex offences, compared to the control groupcontrol group

Arson -continuedArson -continued

Nearly half of the offences occur in a Nearly half of the offences occur in a setting of direct conflict with setting of direct conflict with authority authority

The majority of the arsonists have a The majority of the arsonists have a high incidence of disruptive or high incidence of disruptive or broken homesbroken homes

History of long-term behaviour History of long-term behaviour problems, single or separated problems, single or separated parentsparents

Arson-continuedArson-continued Scott, 1978,Scott, 1978, separated fire setting into separated fire setting into

motivated and motiveless groupsmotivated and motiveless groups In the motivated group there was a clear motive In the motivated group there was a clear motive

of profit, such as revenge, concealments of other of profit, such as revenge, concealments of other crimes or sometimes political or racial reasonscrimes or sometimes political or racial reasons

In the motiveless group there was no noticeable In the motiveless group there was no noticeable or rational motive. Many had histories of or rational motive. Many had histories of repeated episodes, history of Schizophrenia or repeated episodes, history of Schizophrenia or Manic Depression and responding to Manic Depression and responding to hallucinations or delusions.. hallucinations or delusions..

The vast majority of the intellectual disability The vast majority of the intellectual disability arsonists fall in to the motiveless group arsonists fall in to the motiveless group