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Criminal | Defences

Intoxication: Criteria

Revision Note | A Level

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  • intoxication does not provide a defence in itself
  • it is relevant in determining whether D has the required mens rea
  • if D lacks sufficient mens rea due to his intoxicated state then he may be found not guilty

Nature of intoxication

  • law distinguishes between voluntary and involuntary intoxication


  • occurs when D chooses, of his own free will to become intoxicated, with alcohol, illegal drugs or any intoxicants
  • in general D should not be excused from consequences of their actions if voluntarily intoxicated
  • because D is responsible for being in such a state
  • if the intoxication prevented D from having necessary mens rea, the charge cannot be proved

    Gallagher (1963)

    • D stabbed V, his wife, to death
    • D bought a bottle of whiskey at same time as the knife, D drunk most of the bottle
    • D found guilty of murder, held D had necessary mens rea despite his intoxication


  • covers situations where D did not know he was taking an intoxicating substance
  • can occur if a drink is spiked or a prescribed drug has an unexpected effect
  • for involuntary intoxication defence must be proved the intoxication prevented D from forming required mens rea
  • intoxication causing lack of inhibition may not be sufficient

    Kingston (1994)

    • D, a homosexual with paedophiliac predilections, charged with indecent assault on V, 15 yr old boy
    • V and D were drugged without their knowledge, D photographed performing gross sexual acts with V, as part of plot to blackmail D
    • House of Lords found intoxicant had removed the inhibitions of D, so he engaged in acts he would not have if sober, but involuntary intoxication did not excuse this behaviour even where D had been drugged by fraud
  • unanticipated strength of intoxicant does not make intoxication involuntary

    Allen (1988)

    • D committed sexual assaults
    • D had been drinking homemade wine, D argued it was much stronger than he realised
    • held involuntary intoxication does not occur when D voluntarily takes an intoxicant not realising strength
  • non dangerous drugs may lead to involuntary intoxication

    Hardie (1985)

    • D charged with arson after setting fire to a wardrobe in his flat
    • D was depressed as his wife had told him to leave, D took valium to calm himself down, D slept for most of the day and then set fire to the wardrobe
    • court decided did not necessarily amount to voluntary intoxication, D had taken valium believing it would calm him down, the normal effect, so had not been reckless
    • court found there was a distinction between dangerous drugs, ..where it is common knowledge.. [the taker] may become aggressive or do dangerous or unpredictable things... and non dangerous drugs, such as valium

Nature of intent

  • law distinguishes between basic and specific intent offences
  • principle is that intoxication can be a defence to crimes of specific intent and not to those of basic intent

    Majewski (1976)

    • D attacked Vs in a pub
    • D was very intoxicated, after drinking and taking drugs, D convicted of three offences of ABH, under S47 of the Offences Against the Person Act 1861 (OAPA 1861)
    • House of Lords upheld D’s conviction, held that self induced (voluntary) intoxication can only be raised in defence to crimes of specific intent not basic intent offences

Specific intent

  • specific intent crimes are sometimes summarised as offences requiring mens rea
  • murder and S18 offence (under OAPA 1861) are considered specific intent crimes

    Sheehan and Moore (1975)

    • Ds threw petrol over V and set fire to him, V died
    • Ds found to be too drunk to have formed the necessary mens rea to kill or cause grievous bodily harm
    • held Ds did not have the necessary specific intent needed for mens rea for murder, Ds guilty of involuntary manslaughter, as that is a basic intent offence

Basic intent

  • difficulty arises with defining which offences are basic intent
  • seems basic intent refers to general criminal intent, rather than any ulterior intent D wants to achieve from his actus reus
  • voluntary intoxication provides no defence to basic intent crime, as the choice to become intoxicated is reckless
  • D knows that there is a risk he will behave badly or criminally when intoxicated

    Majewski (1976)

    • Lord Elwyn Jones:.. If a man of his own volition takes a substance which causes him to cast off the restraints of reason and conscience, no wrong is done to him by holding him answerable criminally for any injury he may do while in that condition... reducing himself by drugs and drink to that condition in my view supplies the evidence of mens rea, of guilty mind certainly sufficient for crimes of basic intent. It is a reckless course of conduct and recklessness is enough to constitute the necessary mens rea in assault cases...
  • basic intent crimes can be summarised as offences requiring a mens rea of recklessness
  • offences classified as basic intent: assault, battery, S47 and S20 offences (under OAPA 1861) and involuntary manslaughter
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