1. Diminished Responsibility

2.  The Homicide Act 1957 s2(1) provides a defence where D:  ‘...was suffering from such abnormality of mind (whether arising from a condition of arrested or retarded development of mind or any inherent causes or induced by disease or injury) as substantially impaired his mental responsibility for his acts and omissions in doing or being a party to the killing.’

3. Effect Diminished responsibility is a partial defence, which applies only to murder. If pleaded successfully, it will reduce the defendant’s liability from murder to that of manslaughter and thus allow him or her to avoid the mandatory life sentence. Voluntary manslaughter: diminished responsibility

4.  The defences ONLY apply to murder  They reduce it to manslaughter  This means the sentence is at the judge’s discretion  Circumstances can be taken into account  The burden of proof is on the defendant to prove diminished responsibility on the balance of probabilities

5. Introduction Voluntary manslaughter was introduced by Parliament via the Homicide Act 1957. It was designed to cover the situation where the defendant has both the actus reus and mens rea of murder but the surrounding circumstances of the offence mean that the defendant’s liability is reduced from murder to manslaughter. These relevant circumstances amount to partial defences specific to a murder charge and are defined by the Homicide Act as diminished responsibility, provocation and suicide pacts. Voluntary manslaughter

6. Definition Diminished responsibility is defined in s.2 of the Homicide Act 1957: ‘Where a person kills or is party to a killing of another, he shall not be convicted of murder if he was suffering from such abnormality of mind (whether arising from a condition of arrested or retarded development of mind or any inherent causes or induced by disease or injury) as substantially impaired his mental responsibility for his acts and omissions in doing or being a party to the killing.’ Voluntary manslaughter: diminished responsibility

7.  Replaces section 2(1) of the Homicide Act with new subsections (1) to (1B)

8.  The ‘abnormality of mind’ as expressed in the 1957 Act is replaced by the words ‘abnormality of mental functioning’ in the new Act.  This abnormality of mental functioning must:  A) arise from a recognised medical condition  B) substantially impair the defendant’s ability to do one or more of the following: 1. Understand the nature of his conduct 2. Form a rational judgment 3. Exercise self control

9.  The abnormality of mental functioning provides an explanation of the defendant’s conduct if it causes, or is a significant contributory factor in causing, the defendant to act as he did  A defendant who puts forward this defence must prove it on the balance of probabilities

10. Under the 1957 Homicide Act ‘abnormality of mind’ has been held to cover many different kinds of medical condition, such as:  Psychotic disorders – Byrne (1960)  Clinical depression and epilepsy  Post -natal depression – Reynolds (1988)  PMT (Pre-menstrual tension) – English (1981)  BWS (Battered wife syndrome) – Ahluwalia (1992)

11. The C&JA 2009 recognises that there are many existing lists which classify accepted physical, psychiatric and physiological conditions – foremost is the: World Health Organisation’s international classification of diseases American Psychiatric Association’s diagnostic and statistical manual of mental disorders If a jury accepts that, at the time of the killing, a defendant was suffering from a condition included in one of these lists then the test above will be met. If there is a new or emerging condition that is not on the list, a validated specialist can be called to give evidence.

12. The Homicide Act 1957 required that a person’s mental responsibility must be substantially impaired, but it did not specify in which way. The Coroners and Justice Act 2009 attempted to clarify this.

13. The abnormality of mental functioning has to be a significant contributory factor in causing the defendant to act as he did. It need not be the only cause, the main cause, or the most important factor. It must however, be more than merely trivial. There must be a causal (not casual!) connection between the abnormality and the killing in order for the defence to succeed. The defence should not be able to succeed where the defendant’s mental condition made no difference to his behaviour; that he would have killed regardless. (apply this point to Gittens, and Dietschmann)

15.  Abnormality caused by drink or drugs would not usually be accepted  There may be an exception if the abnormality is caused by the disease of alcoholism  But not by the voluntary taking of alcohol  See Tandy  Why did the defence fail?  It is more difficult where D is intoxicated in addition to suffering from one of the stated causes as in Dietschmann

16.  Read the case of Dietschmann carefully  The Court of Appeal were unsure about how the law should apply  The case went to the House of Lords for clarification  What did the House of Lords decide?

17.  Can you comment on the problems with this issue?  It is very difficult for the jury  They must try to decide if the abnormality would have substantially impaired D’s mental responsibility regardless of the intoxication  It may be hard to disentangle the two if D was affected by both intoxication and another ‘cause’  The effect of drink can contribute as long as the other ‘cause’ played a more than trivial part in impairing D’s responsibility  The law is not very clear on this

18.  The defence has been raised in many different circumstances based on a wide range of causes, from Gulf War syndrome to pre-menstrual tension  In Martin, although self-defence failed, he succeeded in arguing diminished responsibility as he had a ‘paranoid personality disorder’  In several ‘mercy’ killing cases the defence has succeeded - see case study

19. The requirements are: An abnormality of mind Caused by arrested or retarded development of mind or an inherent cause or disease or injury Which substantially impairs D’s responsibility

20.  The burden of proof is on the defendant rather than the prosecution  The wording of the Homicide Act is unclear  Medical evidence has moved on since 1957  It can also be complex and confusing for the jury  It is often contradictory  The jury may ‘find’ diminished responsibility where they feel there is moral justification for the killing (as in euthanasia cases)

21. Burden and standard of proof The defendant must prove, on the balance of probabilities, that he or she was suffering from diminished responsibility at the time of the killing. Medical evidence will be required from at least two experts in order to substantiate any such claim. Voluntary manslaughter: diminished responsibility

22. Evaluation (1) The Law Commission recently reviewed the area of voluntary manslaughter in its paper ‘Partial Defences to Murder’ (Consultation Paper No 173). Meaning unclear Critics argue that it is unclear precisely what the term ‘diminished responsibility’ means. There is little to assist in determining what constitutes an ‘abnormality of mind’ – it is simply and tautologically defined as a state of mind that is ‘abnormal’. There are also difficulties in trying to determine whether the defendant’s mental responsibility has been ‘substantially impaired’. Voluntary manslaughter: diminished responsibility

23. Evaluation (2) Burden of proof rests with the defendant Opponents of the current law say that the burden of proof should be changed so that the onus is on the prosecution. Labels those in abusive relationships as mentally abnormal In order to rely on the defence of diminished responsibility, those in abusive relationships who kill their abusers must claim to be mentally abnormal. Critics say that this should not be the case and far more emphasis should be placed on the abuse that they have suffered rather than their state of mind. Voluntary manslaughter: diminished responsibility

24. Evaluation (3) Courts too ready to accept the defence in some cases The courts have been criticised for being too willing to accept the defence of diminished responsibility in some instances. In some cases involving euthanasia, the courts may take the view that the defendant does not deserve to be labelled a murderer and face the accompanying life sentence, and so accept a plea of diminished responsibility on the basis of little evidence. Despite their good intentions, this is seen by many as a misuse of the defence. Voluntary manslaughter: diminished responsibility

25. Reform In its recent review, the Law Commission found that there had been a fall in the successful use of the diminished responsibility defence. However, it stated that the defence appeared to be working and advocated its retention as long as the mandatory life sentence for murder remains. No radical changes were proposed. Voluntary manslaughter: diminished responsibility