Mental Illness and Offending


What is Mental Illness?

  • It is a collection of psychological conditions which have a characteristic that disables and/or distresses impairments in different aspects of an individual’s psychological functioning

  • The meaning is different between law and psychology

  • Very common among general population

  • Approx. 450 million people across the world have a mental health problem according to the world health organisation

  • ONS Psychiatry Morbidity Report states 1 in every 4 British adults will experience at least one diagnosable mental health problem a year

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Mental Health Act 2007

  • Mental Illness defined as any disorder of the mind

  • Personality disorders

  • Learning Disabilities

  • Autism Spectrum Disorders

  • Eating Disorder

  • Many believe that individuals with mental illnesses should receive specialist mental health treatment instead of punishment

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Offenders with a Mental Impairment

  • 72% of male prisoners and 70% of female prisoners suffer a mental disorder

  • Out of 500 homicide cases in England and Wales in 1996/7..

  • 44% had a recorded mental disorder at some point in their life

  • 14% displayed symptoms of mental illness at the time of the offence

  • 8% were in contact with mental health service in the year prior to the offence

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  • Axis I = Clinical disorders like depression or schizophrenia

  • Axis II = Personality disorders or mental retardation

  • Axis III = General medical conditions

  • Axis IV = Psychosocial and environmental problems

  • Axis V = Global Functioning

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Clinical Aspects of Violence

  • Command hallucinations are voices that tell the individual to do a certain act (in some cases this act is a crime) e.g. the Yorkshire ripper

  • Smith and Taylor 1999 carried out a study on male schizophrenic sex offenders…

  • 94% had a form of delusion and/or hallucinations at time of offence

  • 51% of these offenders stated the delusions were coincidental and had no bearing on attack

  • 25% said their delusions were of a sexual or persecutory nature however did not reflect the characteristics of the assault

  • 18% said that the delusions appeared to be directly related to the sexual assault

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McNeil 1997

  • Discovered that a previous history of violent behaviour is the best predictor of future violence

  • Gender is a poor predictor of violence

  • Being victimised increases the risk of acting violently

  • Care givers and nurses are at the greatest risk

  • Poor social networks can be associated with violence

  • Some environments can be viewed as threatening

  • Homelessness / vagrancy can be associated with violent behaviour

  • The availability of a weapon increases the risk of violent behaviour

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Dealing with Offenders Suffering a Mental Impairme

  • Criminal Justice System

  • Medical Services

  • Voluntary Services

  • Communities

  • Families

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Mental Illness and the Criminal Justice System (En

  • In England and wales an appropriate adult is appointed and diverted into the psychiatric system

  • If individual does not understand the difference between a guilty plea and a no guilty plea they will be unfit to make the plea

  • The Judge can decide that it is undesirable for the individual to give evidence, instead they will remand them to a hospital to be treated

  • If the individual does plead guilty with psychiatric evidence then the most common outcome will be a hospital order, however in some cases the individual may end up in prison, or with community treatment

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Mental Illness and the Criminal Justice System (US

  • The Miranda Rights protect individuals however these can be waived as result of mental illness, which puts the individual at risk

  • The individual is assessed and if decided unfit to plead they can be sent to a unit until they show they are competent enough to make a plea if done within a reasonable amount of time

  • The most common result is that the individual is sent to prison and receives psychiatric treatment while serving their sentence

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Aggravating and Mitigating Factors of Release

  • The Parole Board has a Case review and will consider the individuals…

  • Behaviour in prison

  • Plans when they are released

  • Likelihood of reoffending, whether or not they are a danger to public

  • Reason for the sentence in the first place

  • Any previous offences

  • What was said by the Judge when the offender was first sentenced

  • The victim impact statement

  • Any medical, psychiatric and psychological evidence for or against the offender

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  • Not much doubt about some forms of mental illness alleviating the likelihood of criminal behaviour

  • It is difficult to identify the most likely to be violent and/or criminal from the mentally ill

  • There are other factors, such as  alcohol or drug abuse that have larger effects on mental illness

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