Thursday, 14 January 2016

What is “Mental Disorder” Within the Meaning of the Mental Health Act?

Stephen Fry simulating the "head clutch" stock photos
used to illustrate any article involving mental disorder
The legal definition of “mental disorder” for the purposes of the Mental Health Act has evolved over the years to reflect changes in Society and the liberalisation of psychiatry.
The Mental Health Act 1959 began a major process of revision in the way people with mental disorder were treated by the law. Indeed, one of the first things the 1959 Act did was to repeal ancient legislation. The long title of the 1959 Act was:
“An Act to repeal the Lunacy and Mental Treatment Acts, 1890 to 1930, and the Mental Deficiency Acts, 1913 to 1938, and to make fresh provision with respect to the treatment and care of mentally disordered persons and with respect to their property and affairs; and for purposes connected with the matters aforesaid.”
It is salutary to realise that in the early part of the 20th century people with a learning disability were officially classified as “mentally deficient”.
The 1959 Act, however, in defining mental disorder, introduced different legal terminology. There were now two terms to be used for such people: “subnormality” and “severe subnormality.”
“Subnormality " meant “a state of arrested or incomplete development of mind (not amounting to severe subnormality) which includes subnormality of intelligence and is of a nature or degree which requires or is susceptible to medical treatment or other special care or training of the patient”, while "severe subnormality" meant “a state of arrested or incomplete development of mind which includes subnormality of intelligence and is of such a nature or degree that the patient is incapable of living an independent life or of guarding himself against serious exploitation, or will be so incapable when of an age to do so.”
The original MHA 1983 changed the terminology again. “Severe subnormality” was now known as “severe mental impairment”, and “subnormality” as “mental impairment”, but in order for such a patient to be regarded as mental disordered and therefore eligible to be detained under the MHA their impairment also had to be associated with “abnormally aggressive or seriously irresponsible conduct”.
The 1959 Act also had a category of “psychopathic disorder”. This was defined as “a persistent disorder or disability of mind (whether or not including subnormality of intelligence) which results in abnormally aggressive or seriously irresponsible conduct on the part of the patient, and requires or is susceptible to medical treatment.”
This meant that for a person to be detained in hospital for treatment under Sec.26 (the forerunner of Sec.3), they had to be suffering from mental disorder, the definition of which was regarded as either “in the case of a patient of any age, mental illness or severe subnormality”, or “in the case of a patient under the age of twentyone years, psychopathic disorder or subnormality”. The Mental Welfare Officer (the predecessor of the AMHP) had to specify which of these applied to the patient on their application form.
Indeed, I recall on one occasion many years ago detaining a 17 year old female under Sec.26 MHA 1959 on the grounds of psychopathic disorder. She had been an informal patient on the local psychiatric ward, which at that time was a ward within the local general hospital. The application was precipitated by her sneaking out of the ward onto the maternity ward, which was upstairs, and attempting to abduct one of the babies.
“Psychopathic disorder” remained one of the specific grounds for detention under Sec.3 MHA until it was finally removed by the 2007 Act.
The full definition of mental disorder in the 1959 Act was: “mental illness, arrested or incomplete development of mind, psychopathic disorder, and any other disorder or disability of mind “. This definition remained unchanged when the 1983 Act was introduced, and was only altered by the 2007 Act. The current definition is now “any disorder or disability of the mind”.
Both the 1959 Act and the 1983 Act specified certain exclusions. The 1959 Act stated that behaviour consisting “only of promiscuity or other immoral conduct” could not be construed as mental disorder, while the 1983 Act additionally excluded “sexual deviancy or dependence on alcohol or drugs”.
Curiously, the original Sec.1(3) stated:
“Nothing in subsection (2) above shall be construed as implying that a person may be dealt with under this Act as suffering from mental disorder, or from any form of mental disorder described in this section, by reason only of promiscuity or other immoral conduct, sexual deviancy or dependence on alcohol or drugs.”
But the 2007 Act replaced this subsection with: “Dependence on alcohol or drugs is not considered to be a disorder or disability of the mind for the purposes of subsection (2) above.” This appears to imply that promiscuity, immoral conduct and sexual deviancy can now be regarded as a mental disorder.
So what is now meant by “mental disorder” within the meaning of the Act?
The Code of Practice goes into this at some length. It notes that: “Relevant professionals should determine whether a patient has a disorder or disability of the mind in accordance with good clinical practice and accepted standards of what constitutes such a disorder or disability.”
It then goes on to give an extensive, but not exhaustive, list of “clinically recognised conditions which could fall within the Act’s definition of mental disorder” (para2.4). These include:
·       Affective disorders, such as depression and bipolar disorder
·       Schizophrenia and delusional disorders
·       Neurotic, stress-related and somatoform disorders, such as anxiety, phobic disorders, obsessive compulsive disorders, post-traumatic stress disorder and hypochondriacal disorders
·       Organic mental disorders such as dementia and delirium (however caused)
·       Personality and behavioural changes caused by brain injury or damage (however acquired)
·       Personality disorders
·       Mental and behavioural disorders caused by psychoactive substance
·       Eating disorders, non-organic sleep disorders and non-organic sexual disorders
·       Learning disabilities
·       Autistic spectrum disorders (including Asperger’s syndrome)
·       Behavioural and emotional disorders of children and young people
There are, however, extensive caveats regarding the use of compulsory powers for some of these disorders, giving very useful guidance on how such disorders as Autistic Spectrum Disorder, Asperger’s Syndrome and personality disorder should be approached. These are covered at length in Chapters 20 & 21.
The Code suggests that in relation to people with learning disability or autism “evidence-based good practice is that most of their needs can best be met at home or in community settings” (para20.5). It goes on to say that “compulsory treatment in a hospital setting is rarely likely to be helpful for a person with autism, who may be very distressed by even minor changes in routine and is likely to find detention in hospital anxiety provoking” (para20.20), and encourages less restrictive approaches to managing such people.
We now have a situation in which almost any mental health problem can be considered to be a mental disorder within the meaning of the MHA. This is not to suggest that the requirements for detention under the Act have been compromised, as in many ways the new Code has imposed further restrictions of the use of the Act, especially stressing the impact of Human Rights legislation on AMHP practice.
The new Code sets out from the first paragraph that practice should always begin with the “least restrictive option”, on the basis that “where it is possible to treat a patient safely and lawfully without detaining them under the Act, the patient should not be detained” (para1.1). That should always be the first guiding principle informing AMHP practice.


  1. Great summary of how perceptions of mental illness/ disorder have developed since the war, masked amhp.

    Have you heard that the big US corp that has just taken over Priory/ Parnerships for Care refers to these private MH services as for 'behavioural health' - will that be the new terminology in future?

  2. It being a human right not to be deprived of one's liberty, even if suffering from a mental disorder, the 'least restrictive option' - particularly as viewed by the patient - should be the starting point of all mental health practice. But my experience in Scotland has been that in practice the 'right of access' to compulsory treatment in hospital is the paramount 'human right', and the opinion of the AMHP over-rides the views and wishes of the patient. Policy and practice do not match up. I have no experience of mental health tribunals in England & Wales, but I wonder if the situation is really any better than in Scotland.