1. Self Defence/Prevention of a Crime

2. Definition D admits AR and MR of offence
A person can use force as is reasonable in the circumstances to defend himself or another or his property

3. Private Defence Common Law defence
A person can use such force as is reasonable in the circumstances if he is:
Defending himself or his property against an actual or imminent attack; or
Defending another against such an attack

4. Public Defence
Criminal Law Act 1967 – person may use such force as is reasonable in the circumstances in order to:
Prevent the commission of an offence; or
Effect a lawful arrest

5. Requirements for the Private and Public Defence
Both defences clarified by S.76 Criminal Justice and Immigration Act 2008
Both defences have the following requirements:
Necessity of force
Reasonableness of force

6. Necessity of Force
Use of force is not justified if it is not necessary
It will be seen to be necessary if it is seen to be so in the circumstances which exist or which D genuinely believed existed (subjective)
Gladstone Williams – a man saw a woman being robbed by a youth. He struggled with the robber to try and stop him and hand him to the police. D appeared at this point and thought the man was attacking the youth. He stepped in to protect the youth. D was successful in pleading prevention of a crime, even though he was mistaken as to the actual facts. His defence was based on what he genuinely believed was happening
S.76(5) Criminal Justice and Immigration Act 2008 – D cannot rely on a mistaken belief caused by voluntary intoxication
O’Grady – D who was drunk hit a friend over the head in the mistaken belief that the friend was trying to kill him – defence rejected

7. Necessity of Force – Imminent Attack
Defence comes into operation even if attack has not yet taken place providing it is imminent
i.e. – D can get in with the first blow
But difficult to establish the force he uses is reasonable
Bird – D does not have to wait for an attack to start but can get in the first blow
A-G’s Reference (No. 2 of 1983) – D prepared petrol bombs in fear pf an attack on his shop – held that D can make advance preparations in self-defence

8. Reasonableness of Force
Jury must decide whether, in all the circumstances, the D used reasonable force
Palmer – things to consider for reasonableness:
Was it sensible and clearly possible to take some simple avoiding action?
Was the attack on D serious and dangerous?
Was D’s retaliation proportionate to the necessities of the situation?
Was D’s actions revenge or punishment? – i.e. if the attack is over
Must recognise that a person defending themselves “cannot weigh to a nicety the exact measure of his necessary defensive action”

9. Reasonableness of Force – Excessive Force
Clegg – D was a soldier in Northern Ireland before the peace settlement. D was at a road checkpoint when a car came towards him at high speed. Seeing it was not going to stop, he fired at it . Last shot hit a girl passenger in the back seat and killed her. Evidence showed the car had already passed him when he fired the final shot. Held that in the circumstances neither he nor anyone else was any longer in danger. Plea of self- defence/defence of another failed, D guilty of murder
Martin (Anthony Edward) – D lived in an isolated farmhouse which had been burgled in the past. D woken by sounds of someone entering his property, took his shotgun and fired without warning into the darkness. One of the intruders, 16 year old, shot in back and died. Plea of self- defence failed as force was unreasonable

10. Reasonableness of Force – Criminal Justice and Immigration Act 2008
S.76(6) – the degree of force used by D not to be considered as reasonable in the circumstances as he believed them to be if it was disproportionate in those circumstances
S.76(7) – guidance as to whether degree of force used was reasonable in the circumstances:
A person acting for a legitimate purpose may not be able to weigh to a nicety the exact measure of any necessary action; and
Evidence of D having only done what he honestly and instinctively thought was necessary for a legitimate purpose constitutes strong evidence that only reasonable force was taken

11. Burden of Proof
Burden is on Prosecution to prove to the jury beyond all reasonable doubt that D was either:
Not acting to defend himself or another
Not acting to defend property, or not acting to prevent a crime or apprehend an offender; or
If he was so acting, the force was excessive

12. Questions on Self-Defence
First consider the original offence as you normally would – AR and MR
Then consider the defence
Was there a necessity for the force?
In the circumstances as they actually exist? or
In the circumstances as they are genuinely believed to be by D?
But remember if D is voluntarily intoxicated, he cannot rely on his mistaken belief
There can still be necessity even if an attack hasn’t occurred yet provided it was imminent
Was the force used by D reasonable in the circumstances as D perceived them?
Was the force excessive? Was the threat still present or had it passed? Was the amount of force unreasonable?