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Criminal | Defences

Self Defence & Crime Prevention: Criteria

Revision Note | A Level

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  • common law developed a concept of reasonable self defence (private defence)
  • there is statutory law covering public defence, in relation to prevention of crime

    Criminal Law Act 1967

    • S3(1) A person may use such force as is reasonable in the circumstances in the prevention of crime, or in effecting or assisting in the lawful arrest of offenders or suspected offenders or of persons unlawfully at large
  • overlap between the two but also distinction, self defence may be used against someone who is not actually committing a crime, for example if perpetrator is insane

Necessity of force

  • first question is whether the force was necessary
  • point decided by the jury
  • general principle is that the use of force is not justified

Genuine belief

  • use of force can be found necessary if it is seen to be so in the situation that exists or that D believes exists

    Gladstone Williams (1987)

    • D saw a man struggling with a youth who was calling for help and intervened
    • in fact, the man was affecting a lawful arrest of the youth
    • D found not guilty of assault, D honestly believed that he was preventing an unlawful assault, so his actions were justified even though he had misunderstood the situation
  • statutory basis to defence for Ds who genuinely hold a mistaken belief (Criminal Justice and Immigration Act (CJIA) 2008)
  • S5 of CJIA 2008 sets out that this does not necessarily apply if D is voluntarily intoxicated

Pre emptive action

  • defence can also apply to an imminent attack

    Bird (1985)

    • D was at her 17th birthday party and V, her ex-boyfriend arrived with his new girlfriend
    • D and V argued and she asked him to leave, V did so but later returned and the argument continued
    • D threw a drink over V, V pinned D against a wall and V punched D in the face, causing V to lose his eye
    • D claimed she had forgotten that she had a glass in her hand, which had subsequently broken, D charged with wounding under S20 of Offences Against Person Act 1861
    • D argued self defence, judge directed jury that to rely on self defence, D must demonstrate that she did not want to fight, D convicted of S20 offence
    • conviction quashed on appeal, held there was no obligation to demonstrate an unwillingness to fight
  • seems that withdrawing or demonstrating an unwillingness to fight can be used as evidence that D is acting reasonably and in self defence
  • but there is no absolute obligation to retreat

    Beckford (1988)

    • Lord Griffiths: .. A man about to be attacked does not have to wait for his assailant to strike the first blow, or fire the first shot, circumstances may justify a pre-emptive strike...

Reasonableness of force

  • jury must decide if the force used was reasonable
  • the standard is what is reasonably necessary

    Palmer (1971)

    • Lord Morris: .. it is both good law and good sense that a man who is attacked may defend himself... he may do, but may only do what is reasonably necessary...
  • self defence may occur immediately before or during a perceived attack

    Clegg (1995)

    • D, a soldier at a checkpoint, shot and killed V, a car passenger
    • a stolen car, came towards D at speed, D shot at car
    • evidence proved shot which killed V had been fired once the car had passed, so no argument for self defence
    • D's conviction for of murder upheld on appeal
  • unreasonable force may not be used

    Martin [2002]

    • D shot intruders at his home, one died and the other was seriously injured
    • D heard the intruders and feared they may be violent towards him
    • D’s appeal on the ground of self defence was rejected, as he was found to use unreasonable force
    • court reduced the conviction to manslaughter on the basis of diminished responsibility, as D suffering from a longstanding paranoid personality disorder
  • statute recognises that someone under attack is under stress, so may not be able to reason as precisely

    Criminal Justice and Immigration Act 2008

    • S76(7) .. [in deciding whether the force used is reasonable] the following considerations are to be taken into account (so far as relevant in the circumstances of the case)-
    • S76(7)(a) that a person acting for a legitimate purpose may not be able to weigh to a nicety the exact measure of any necessary action; and
    • S76(7)(b) that evidence of a person's having only done what the person honestly and instinctively thought was necessary for a legitimate purpose constitutes strong evidence that only reasonable action was taken by that person for that purpose.
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