Jim may be able to raise some issues of self-defence to prove these actions lawful. The rules relating to public defence are laid down in the Criminal Law Act 196717. Section 3 (1) tells us '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' and section 3 (2) 'subsection (1) above shall replace the rules of the common law on the question when force used for a purpose mentioned in the subsection is justified by that purpose'.
Therefore if Jim has used reasonable force in apprehending Philip, this defence should succeed. In Owino18 it was held that the defendants view of what is reasonable in the circumstances is not relevant to the defence, thus it is down to the jury to decide how they believe a reasonable man would act in the circumstances, meaning the test as to whether Jim has acted reasonably will be an objective one. On this issue, it needs mentioning that even if Phillip hadn't actually stolen Jim's phone that doesn't matter since Beldam LJ stated in his judgement in Scarlett19 '… he is not to be convicted even if his belief is unreasonable.
' So even if Phillip hasn't actually done anything wrong as long as at the time of using the force Jim honestly believed he had done, then public-defence can still succeed as justification for his actions (Gladstone20). Because of the confusion this area of law has gone through, the law Commission proposed to change 'common assault' in their report21. A draft Bill put forward in 199822, would see assault/battery as 'intentionally or recklessly applying force to or causing impact on the body of another, or intentionally or recklessly causing the other to believe that such force or impact is imminent'
The next issue that needs discussion is any possible liability that Bertrand may incur as a result of his actions. When he believes Jim is assaulting Phillip he starts to hit Jim with his stick, and even when Phillip has escaped he continues to hit him, eventually causing cuts to his face. With regards to any liability for these attacks, because of the use of a weapon and the cuts Jim suffers the most likely offence that has been committed prima facie may be Grievous Bodily Harm23 or Actual Bodily Harm24(ABH being discussed earlier).
For Bertrand to be convicted of a Section 20 offence then there are further actus reus and mens rea elements required. GBH is defined as 'whosoever shall unlawfully and maliciously wound or inflict and grievous bodily harm upon any other person, either with or without any weapon or instrument shall be guilty of an offence, and being convicted thereof shall be liable to imprisonment for not more than five years'. The actus reus of the offence only differs from S. 47 in the extent of harm inflicted, thus there must be an unlawful wounding or the infliction of grievous bodily harm.
The mens Rea therefore is intent to do some kind of bodily harm or recklessness as to whether any such harm might be caused, with the harm intended or foreseen by the defendant needing not to amount to a wound or grievous bodily harm. Despite Bertrand's intent to do as he did, a s20 charge seems unlikely because of Moriarty25 and M'loughlin26 which suggest to us that both layers of the skin must be broken (the dermis and epidermis) which are very serious cuts, and there is no mention of this on the facts.
Consequently, a conviction of ABH s47 seems the most likely because the injuries don't carry the severity required for a s20 offence, despite Bertrand possessing the further mens rea element required for such an offence. If the prosecution could satisfy the guidelines as explained then a conviction for this s47 offence seems likely. Bertrand's possible liability raises similar issues as discussed earlier in that he was only acting as he was because he believed that Jim was assaulting Phillip, therefore believed he was acting in the prevention of crime (by stopping Jim from assaulting Philip).
Given the facts, this defence seems unlikely to succeed. Once Philip escaped and the threat of harm had subsided, Bertrand continued to hit Jim with the stick. Because of this, and the relevant case law on the matter such a defence may fail. Bertrand may well be seen as the aggressor once Philip has escaped, Bird27 suggests that one factor to take into account (it stresses not the only factor) is that if the defendant tried to call of the fight or retreat from the situation then the defence would have more grounding.
A requirement for self defence is there must be an imminent threat, once Philip had escaped there was no longer a threat, which could cause his defence to fail. Again, if she was acting because she believed she was preventing crime, once Philip had escaped there was no longer any crime to prevent; thus the defence seems likely to fail. However, a defence of mistake may be raised, and seems very likely to succeed due to the very similar facts of Williams20.
Despite being generally known as a 'defence', mistake is more a denial of one of the definitional elements of the crime. Because Bertrand was under the mistaken belief Jim was assaulting Philip then she may well avoid any liability for the injuries she caused Jim, unless this case is distinguished because in Williams the defendant sought clarification, and was misled as to the situation before acting.
Criminal law, 2nd edition 2002 by Tony storey and Alan Libury, willan publishing. Quite Useful. Good clear summaries of the relevant law and a few different ideas to the course books.
Criminal Law, 4th edition 2002 by Catherine Elliot and Fances Quinn, Longman publishing. Very useful. Made the law very clear and understandable.
Criminal Law Text and Materials. Fifth edition CMV Clarkson and HM Keating. Thomson Sweet and Maxwell. The most useful book I used. Gave good coverage of the cases and excellent parts on other writer's comments on the law etc.