If a person of sound mind unlawfully kills another, with the intention to kill or cause grievous bodily harm, the offence of murder is committed.
There are a number of ‘partial defences’ to murder, the most well-known being Provocation (now called loss of control) and Diminished Responsibility. They are called ‘partial’ defences because they ‘reduce’ murder to the offence of voluntary manslaughter. There is only one ‘complete’ defence to murder and that is self-defence.
Self-defence
A defendant has a defence if he uses reasonable force to:
- Defend himself.
- Defend others.
- Defend property.
- Prevent crime.
- Assist with a lawful arrest.
Self-defence (including defence of another) and the defence of property are common law defences. There is a separate statutory defence under section 3(1) of the Criminal Law Act 1967 (CLA), which allows the use of reasonable force in the prevention of crime or in effecting, or assisting in, a lawful arrest. Section 5 of the Criminal Damage Act 1971 provides a specific defence for protection of property.The common law defences of self-defence and defence of property may overlap with the statutory defence of prevention of crime; a person who uses force to protect himself from an attack is both defending himself and preventing an offence of battery. Although the above defences are general defences, they are most commonly relied on by defendants charged with non-fatal assaults or homicide. A defendant will have a defence at common law or under section 3(1) of the CLA if he used reasonable force. This requires consideration of whether it was necessary to use force as well as whether the amount of force was reasonable in the circumstances (R v Palmer [1971] AC 814). The defence will succeed if the defendant used such force as was (objectively) reasonable in the circumstances as he (subjectively) believed them to be (R v Williams [1987] 3 All ER 411; R v Owino [1996] 2 Cr App R 128). Both defences are generally available to defendants, however in some cases only the common law or statutory defence will be appropriate.
Loss of Control -Coroners and Justice Act 2009 s54
1) Where a person (“D”) kills or is a party to the killing of another (“V”), D is not to be convicted of murder if—
(a) D’s acts and omissions in doing or being a party to the killing resulted from D’s loss of self-control,
(b) the loss of self-control had a qualifying trigger, and
(c) 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.
(2) For the purposes of subsection (1)(a), it does not matter whether or not the loss of control was sudden.
(3) In subsection (1)(c) the reference to “the circumstances of D” is a reference to all of D’s circumstances other than those whose only relevance to D’s conduct is that they bear on D’s general capacity for tolerance or self-restraint.
(4) Subsection (1) does not apply if, in doing or being a party to the killing, D acted in a considered desire for revenge.
(5) On a charge of murder, if sufficient evidence is adduced to raise an issue with respect to the defence under subsection (1), the jury must assume that the defence is satisfied unless the prosecution proves beyond reasonable doubt that it is not.
(6) For the purposes of subsection (5), sufficient evidence is adduced to raise an issue with respect to the defence if evidence is adduced on which, in the opinion of the trial judge, a jury, properly directed, could reasonably conclude that the defence might apply.
(7) A person who, but for this section, would be liable to be convicted of murder is liable instead to be convicted of manslaughter.
(8) The fact that one party to a killing is by virtue of this section not liable to be convicted of murder does not affect the question whether the killing amounted to murder in the case of any other party to it.
Diminished Responsibility Homicide Act 1957 Section 2 -
(1) Where a person kills or is a party to the 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.
[(1) A person (“D”) who kills or is a party to the killing of another is not to be convicted of murder if D was suffering from an abnormality of mental functioning which—
(a) arose from a recognised medical condition,
(b) substantially impaired D’s ability to do one or more of the things mentioned in subsection (1A), and
(c) provides an explanation for D’s acts and omissions in doing or being a party to the killing.
(1A) Those things are—
(a) to understand the nature of D’s conduct;
(b) to form a rational judgment;
(c) to exercise self-control.
(1B) For the purposes of subsection (1)(c), an abnormality of mental functioning provides an explanation for D’s conduct if it causes, or is a significant contributory factor in causing, D to carry out that conduct.]
(2) On a charge of murder, it shall be for the defence to prove that the person charged is by virtue of this section not liable to be convicted of murder.
(3) A person who but for this section would be liable, whether as principal or as accessory, to be convicted of murder shall be liable instead to be convicted of manslaughter.
(4) The fact that one party to a killing is by virtue of this section not liable to be convicted of murdershall not affect the question whether the killing amounted to murder in the case of any other party to it
