When a defendant faces a murder charge in court, there are two ‘partial defences’ that can reduce the conviction from Murder to Voluntary Manslaughter. This is important, as it also removes the mandatory life sentence that results from a murder conviction. The two partial defences available are Diminished Responsibility and Loss of Control. Both were recently reformed in the Coroners and Justice Act 2009, after being created originally by the Homicide Act 1957.
Diminished Responsibility - This is defined in section 52 of the Coroners and Justice Act 2009. In order to plead successfully, the defendant must be able to demonstrate the following:
- Abnormality of mental functioning, caused by a recognised medical condition,
- Which provides an explanation for the defendant’s acts or omissions in being party to the killing,
- Which substantially impaired the defendant’s ability to:
- Understand the nature of their conduct
- Form a rational judgement
- Exercise self-control
The burden of proof is on the defendant and the standard of proof is on the balance of probabilities.
Let’s take each of the Diminished Responsibility criteria and examine how the courts have interpreted this partial defence.
Abnormality of mental functioning - In the original partial defence, defined in the Homicide Act 1957, the phrase used was “abnormality of mind”. That phrase was updated to ‘abnormality of mental functioning” to clarify the development of the law through the courts. It was not intended to change how the law should be applied. Therefore precedents set under the old law still operate today.
Lord Parker defined abnormality as: “a state of mind so different from that of ordinary human beings that the reasonable man would term it abnormal.” Abnormal mental functioning is determined by a jury decision, often after hearing medical evidence. It must arise from a recognised medical condition. The term “abnormal” can be interpreted quite widely and has included: pre-menstrual tension, battered woman syndrome, epilepsy, chronic depression and even jealousy. A comprehensive list of recognised medical conditions can be found in the British Classification of Mental Diseases.
It is important to note that juries are not bound by medical evidence - they can choose to ignore it if they wish! A case illustrating this was that of Peter Sutcliffe, AKA the “Yorkshire Ripper”. The medical evidence was overwhelming: Sutcliffe was a paranoid schizophrenic. However, the jury decided to ignore this and they denied him the partial defence of Diminished Responsibility, convicting him of murder.
Provides An Explanation - The abnormality of mental functioning must provide an explanation for the behaviour of the defendant. Simply having a recognised medical condition is not enough, as it could just be coincidental and not be the reason why the killing occurred. Furthermore, it is important to understand that the killing was not the result of an external factor, such as intoxication. Intoxication would not necessarily prevent a defendant from pleading Diminished Responsibility, but they would have to show that they would have killed even if they weren’t intoxicated. Where intoxication does lead to Diminished Responsibility the case can become a little more complex. Long term abuse of drugs and/or alcohol can lead to brain damage. If the defendant was, for example, an alcoholic, they may be able to plead Diminished Responsibility, citing brain damage or Alcohol Dependency Syndrome as their recognised medical condition.
Substantially Impairs - The defendant’s ability to understand the nature of their conduct, form a rational judgement, or exercise self-control must be “substantially impaired”. Impaired means that they may still have some ability. They do not have to have lost all ability. However, the word “substantially” means that the impairment must be more than trivial. If you are answering a scenario question, then look out for evidence that the defendant planned the killing. This might be a sign that the defendant’s ability was not “substantially impaired”, although it would ultimately be up to the jury to decide, as confirmed in the case of R v Eifinger. In 2016, Lord Hughes, in the case of R v Golds, developed the meaning further, arguing that “substantial” should be taken to mean “important or weighty”.
Loss of Control - The partial defence to murder of Loss of Control, again reducing the charge to voluntary manslaughter, is defined in section 54 of the Coroners and Justice Act 2009. In order to plead successfully, the defendant must be able to demonstrate the following:
- A loss of self-control
- The loss of self-control had a qualifying trigger
- A person of D’s sex and age, with a normal degree of tolerance and self-restraint and in the circumstances of D, might have reacted in the same or in a similar way to D.
Loss of Self-Control - The defendant must be able to demonstrate, again on the balance of probabilities, that they had lost control at the time of the killing. Sudden loss of control is not necessary to successfully plead the defence. In the case of R v Ahluwalia, the defendant (under the previous partial defence of provocation) was unsuccessful in her plea, as a period of time had passed before she lost control, killing her husband, after he had threatened her. Under the new law, she would most likely be allowed the defence, providing that she could persuade a jury that she had not acted in a considered desire for revenge.
Qualifying Triggers - A qualifying trigger is the reason why the defendant killed the victim. There are two qualifying triggers allowed by this partial defence, set out in section 55 of the C&JA 2009. Firstly, D’s fear of serious violence from V against D or another identified person. Secondly, a thing or things done, or said, or both, which (a) constitute circumstances of an extremely grave character, and (b) cause D to have a justifiable sense of being seriously wronged. Only one of the two qualifying triggers needs to be proved. Excluded triggers include sexual infidelity, incitement to use violence by D and acting in a considered desire for revenge.
Reasonable Man Test - Finally, to plead the defence successfully, the defendant must show that the following “reasonable man” might also have reacted in the same or a similar way: a person of D’s sex and age, with a normal degree of tolerance and self restraint, and in the circumstances of D. It is important to note, when dissecting a scenario task, that a defendant with a “hot temper” would not typically have a normal degree of tolerance. Furthermore, the circumstances of D can include things like unemployment, as seen in R v Gregson or having a history of abuse, as seen in R v Hill. Medical conditions such as schizophrenia, depression or even epilepsy could also be included as circumstances. However, in cases where the defendant has a medical condition, it is often easier to plead Diminished Responsibility. No matter what, the “circumstances” must be relevant to the defendant’s capacity for tolerance or self-restraint. Voluntary intoxication is not allowed as a circumstance, as demonstrated in R v Asmelash. However, if the defendant would have acted in the same way whilst sober, then the defence should still be available to the defendant.
- Under which section of the Coroners and Justice Act 2009 is Diminished Responsibility defined?
- Who does the burden of proof rest on, for the defence of Diminished Responsibility?
- True or false: chronic depression can be classed as “abnormal”?
- Lord Hughes argued that substantial can be interpreted as “weighty” in the case of R v _____?
- Qualifying triggers are defined under which section of the Coroners and Justice Act 2009?
- True or false: Loss of control must be sudden?