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Criminal | Offences Against The Person

Murder: Liability

Model Answer | A Level

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Discuss liability for murder

Actus reus

Actus reus for murder is drawn from Sir Edward Coke’s definition. There are three key elements - unlawful killing, a reasonable person in being and under the King’s peace.

All killings are unlawful unless deemed justified or authorised.

Liability for murder may arise from an omission if a person has a duty to act, fails to do so and a death occurs. Duties may be imposed through contract (Pittwood (1902)), official position (Dytham (1979)), from special relationship (Gibbins and Proctor (1918)), taken on voluntarily (Stone and Dobinson (1977)) or from setting in motion a chain of events (Miller (1983)).

A reasonable person in being tends not to raise too many issues and only becomes relevant in specific circumstances.

In cases involving a foetus, which is in the womb, it is not seen as independent of its mother so is not defined in the law as in being. If a foetus in womb is deliberately injured and the child dies after being born then the attacker would be criminally liable, although the verdict would likely be manslaughter ( Attorney General’s Reference (No. 3 of 1994) (1997)).

In cases involving a person on a life support machine this aspect must be considered. Doctors have been allowed to switch of life support machines of patients who are deemed ‘brain dead’ without being liable for unlawful homicide. It can be implied that someone considered to be ‘brain dead’ is not a reasonable person in being, although no cases explicitly say this. Life support machines can be seen as simply disguising the underlying damage ( Malcherek (1981)).

Finally, under the King’s peace, provides an exemption for the killing of an enemy during war.


Causation requires the defendant’s actus reus to have caused the victim’s death. If there is no causation, the act is not unlawful or there is no criminal liability.

Factual causation establishes that the defendant can only be found guilty if the consequence would not have happened but for their conduct (Pagett (1983)). If death would have occurred, without the defendant’s actions, then something other than the conduct caused it and factual causation is not present (White (1910)).

Legal causation requires the chain of causation to be unbroken. The cause of death in unlawful killing can vary. The law requires the defendant’s conduct to be more than minimal cause of the death but not necessarily substantial (Cato (1976)).

The thin skull rule is a general principle that the defendant must take the victim as he finds them. The particular characteristics, both physical and mental, of the victim are not taken into account (Blaue (1975)).

A novus actus interveniens may break the chain of causation, if the sole cause of death is an independent act.

May be an issue in medical intervention cases but doctors will only be considered to have caused the death if treatment is seriously wrong. In Jordan (1956) treatment had been palpably wrong so defendant was found not have caused the victim’s death.

However the chain of causation may not be broken by errors made in attempt to care for the victim (Smith (1959)) or rare complications (Cheshire (1991)).

The victim’s own act needs to be considered. If the defendant causes the victim to act in a foreseeable way then the victim’s own act will not break the chain of causation (Roberts (1971)). It depends on whether the victim’s conduct is ..within the ambit of reasonableness and not so daft as to make his own voluntary act one which amounted to a novus actus interveniens... (Williams (1992)).

Mens rea

Under Coke’s definition, mens rea of murder is malice aforethought, which can be express or implied. Case law has developed the meaning and there is no requirement for malice to be present (Gray (1965)). Aforethought does not require thinking or planning beforehand, only that intention does not happen after the act.

Mens rea of unlawful killing is satisfied by intention to kill (express intention) or cause grievous bodily harm (implied intention) as decided in Vickers (1957) and confirmed in Cunningham (1981).

Foresight of consequences

When the defendant’s main aim is not to kill or cause serious injury, oblique intention applies, which brings into question defendant’s foresight of consequences.

Under S8 of Criminal Justice Act 1967, the defendant must intend or foresee the result of death or serious injury.

In Moloney (1985) the House of Lords ruled mere foresight of probable death was not sufficient for intention, although it could be used to infer intention by the jury.

The greater the probability of the result, the more likely it was foreseen and if it was foreseen the more likely it was intended (Hancock and Shankland (1986)).

Lord Lane stated a jury should only infer intention if .. death or serious bodily harm was a virtual certainty as a result of the defendant’s actions and that the defendant appreciated that such was the case... (Nedrick (1986)). Ruling was confirmed in Woolin (1998) which added that a jury should only find intention if virtual certainty principle applied.

Foresight of consequences like a rule of evidence, from which jury may choose whether necessary intention exists (Matthews and Alleyne (2003)).

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