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Criminal | Offences Against The Person

Murder: Actus Reus

Revision Note | A Level

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  • murder is an example of unlawful homicide and a common law offence
  • Sir Edward Coke: .. the unlawful killing of a reasonable person in being and under the King’s peace with malice aforethought, express or implied...
  • actus reus has three elements: unlawful killing, a reasonable person in being and under the King’s peace

Unlawful killing

  • lawful killings are those which are deemed justified or authorised, other killings are unlawful
  • justified killing: self defence or in the prevention of crime
  • authorised killing: during wartime or judicial executions


  • may be the result of an omission
  • if a person has a duty to act, fails to do so and a death occurs
  • contractual duty

    Pittwood (1902)

    • D, a railway worker, omitted to shut the gate, V killed by train
    • D guilty of manslaughter
  • duty through official position

    Dytham (1979)

    • D, a police officer, witnessed a violent attack on V, but took no steps to intervene
    • D guilty neglecting to perform his duty to protect the victim
  • duty from special relationship

    Gibbins and Proctor (1918)

    • Ds failed to feed their child, child died of starvation
    • Ds guilty of murder
  • duty taken on voluntarily

    Stone and Dobinson (1977)

    • Ds failed to look after relative living with them, relative died
    • Ds guilty of manslaughter
  • duty arising from setting in motion a chain of events

    Miller (1983)

    • D, a squatter, accidentally set a mattress alight, did not attempt to put out the fire nor summon help
    • D guilty of criminal damage

    Khan [1998]

    • D supplied V with heroin, she overdosed, D did not summon help left her to die
    • D guilty of manslaughter

A reasonable person in being

  • how we categorise life in the application of the law
  • status of a foetus is in question

    Attorney General’s Reference (No. 3 of 1994) (1997)

    • foetus in the womb, not independent of its mother is not defined in the law as in being
    • if foetus in womb is deliberately injured, then child dies after being born then the attacker would be criminally liable, although the verdict would likely be manslaughter
  • someone on a life support machine raises issues
  • doctors allowed to switch of life support machines of patients who are deemed ‘brain dead’ without being liable for unlawful homicide
  • 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)

    • D attacked V, causing severe injuries which required V to be placed on a life support machine
    • doctors decided to switch machine off stating there was no prospect of recovery, half an hour later V died
    • held the operating and substantial cause of death was the original wounds, D found guilty of murder

Under the King’s peace

  • exemption for the killing of an enemy during war, as such a person is not under the King’s peace
  • however, actus reus of murder would apply to the killing of a prisoner of war

Jurisdiction for prosecution

  • a British citizen can be tried in the domestic courts for a murder alleged to have been committed in any country
  • may be brought anytime after the death
  • if the death occurs over three years after the injuries which caused it then the Attorney General’s permission must be gained
  • permission also applies if a person has already been found guilty of an offence connected to the circumstances of the death


  • actus reus of a crime is D’s guilty act
  • the act must have caused a particular consequence, for murder, death
  • to determine if D’s guilty act caused V's death the rules of causation must be applied
  • if there is no causation, the act is not unlawful or there is no criminal liability

Factual causation

  • D can only be found guilty if the consequence would not have happened but for the D's conduct

    Pagett (1983)

    • D was shooting at police and used V, his pregnant girlfriend, as a human shield, V was killed
    • D convicted of manslaughter, V would not have died but for D’s actions
  • if prohibited result would have occurred, without the D’s actions, then something other than D’s conduct caused it and factual causation is not present

    White (1910)

    • D put cyanide in his mother’s drink intending to kill her, she died of a heart attack before the poison could take effect
    • D had intended to kill his mother and she had died, but his actions were not the cause
    • D not guilty of murder but guilty of attempted murder

Legal causation

  • legal causation must also be proved
  • liability is defined by the link between the act and the consequence
  • chain of causation must be unbroken

Substantial to minimal cause

  • cause of death in unlawful killing can vary, from substantial to minimal
  • law requires conduct to more than minimal cause of the death but not substantial
  • Ds may be found guilty of unlawful homicide if their actions contributed to the death

    Cato (1976)

    • D and V, drug addicts, spent night injecting each other with a mixture of heroin and water, in the morning both felt ill and V died
    • Court of Appeal found heroin was more than a minimal cause which accelerated the V’s death

Thin skull rule

  • general principle is that D must take V as he finds them
  • law does not take into account any particular characteristics of V
  • if V has something unusual about them which makes the injury more serious then D is still liable for resulting injury

    Blaue (1975)

    • D stabbed V, an 18-year-old woman and punctured her lung, at the hospital, V refused a blood transfusion on religious grounds, V died next day
    • held principle D must take V as they find them, applies to the mental as well as the physical characteristics, stab wound caused V’s death

Novus actus interveniens

  • sole cause of injury or death is an independent act

    Malcherek (1981)

    • D attacked V, causing severe injuries which required V to be placed on a life support machine, doctors decided to switch the machine off as there was no prospect of recovery, half an hour later V died
    • held the operating and substantial cause of death was the original wounds, life support had merely held the effect of injuries in suspension
    • no break in causation, D found guilty of murder
  • Medical intervention cases

  • doctors will only be considered to have caused the injury or death if treatment is seriously wrong
    Jordan (1956)
    • D stabbed V, who was taken to hospital
    • a week later the wound had nearly healed, doctors injected antibiotics in error, V had a severe allergic reaction and died
    • medical treatment had been palpably wrong, D’s original action was not the operating and substantial cause of death
    • D guilty of wounding but did not cause V’s death
  • errors made in attempt to care for V may not break the chain of causation
    Smith (1959)
    • D, a soldier, stabbed V in the lung
    • V was dropped twice on the way to the medical centre and given artificial respiration by chest compressions, an hour later V died
    • D argued chain of causation had been broken
    • held D stabbing was the operating and substantial cause of the V’s death, D convicted of murder
  • rare complications in treatment may not break the chain causation
    Cheshire (1991)
    • D shot V in thigh and stomach, V given a tracheotomy, V died of rare complications
    • gunshot wounds were no longer life threatening, tracheotomy and rare complications were not seen as independent of the original act and so the chain of causation was not broken

Victim’s own act

  • if D causes V to act in a foreseeable way then the V’s own act will not break the chain of causation

    Roberts (1971)

    • V jumped from a car in order to escape from D’s sexual advances, car was travelling between 20-40mph
    • D found liable for the injuries
  • depends on whether the V’s conduct is reasonable

    Williams (1992)

    • D tried to rob V, a hitch hiker, V jumped from car and died from head injuries
    • Court of Appeal asked was V’s conduct: ..within the ambit of reasonableness and not so daft as to make his own voluntary act one which amounted to a novus actus interveniens and consequently broke the chain of causation...
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