"It is both good law and good sense that a man who is attacked may defend himself. It is both good law and good sense that he may do, but only do, what is reasonably necessary."

"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."

".... where a forcible and violent felony is attempted upon the person of another, the party assaulted, or his servant, or any other person present, is entitled to repel force by force, and, if necessary, to kill the aggressor ....".

"If there has been an attack so that the defence is reasonably necessary, it will be recognised that a person defending himself cannot weigh to a nicety the exact measure of his necessary defensive action. If a jury thought that in a moment of unexpected anguish a person attacked had only done what he honestly and instinctively thought was necessary that would be most potent evidence that only reasonable defensive action had been taken."

(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

(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.

"You must first ask whether the defendant honestly believed that it was necessary to use force to defend himself at all …

If you are sure that the defendant did not honestly believe that it was necessary to use force to defend himself, he cannot have been acting in lawful self-defence, and you need consider this matter no further. But what if you think that the defendant did honestly believe or may honestly have believed that it was necessary to use force to defend himself?

You must then decide whether the type and amount of force the defendant used was reasonable. Obviously, a person who is under attack may react on the spur of the moment, and he cannot be expected to work out exactly how much force he needs to use to defend himself. On the other hand, if he goes over the top and uses force out of all proportion to the [anticipated] attack on him, or more force than is really necessary to defend himself, the force used would not be reasonable. So you must take into account both the nature of the attack on the defendant and what he then did…".

Insanity.

Where the accused is insane in accordance with the M'Naghten Rules of insanity (see, (1843) 10 Cl & F 200) he will not be entitled, by reason of such insanity, to set the standard of reasonableness as to the degree of force used in self defence. In Oye (Suen) [2013] EWCA Crim 1725 the Court of Appeal observed that section 76 of the Criminal Justice and Immigration Act 2008 included an objective element in the defence of self defence and held (at [47]) that "an insane person cannot set the standards of reasonableness as to the degree of force used by reference to his own insanity". The effect of this is that provided that the first limb of the test is accepted, that is, the accused held a genuine belief in the necessity of using force, then it is a matter for the jury to assess what an objectively proportionate response would be to the situation the accused claimed existed. This, of course, presents quite a problem for a jury in a case where the accused is insane as (presumably) the jury will not have been in such a situation themselves. The particular situation in Oye was that the accused believed that he was about to be exterminated by evil spirits as a result of which he attacked a number of police officers causing serious injury. 

If the accused acts by mistake in using force.

Where the accused believes that he is under attack and acts with reasonable force in self defence to repel the attack, and it turns out that, in fact, he was mistaken and that he was not under attack after all, he will still be entitled to rely upon the defence of self defence, as the court considers the defence from the accused's own viewpoint. In other words, in this regard, the test as to whether the accused was acting in self defence is considered subjectively.

In Oatridge (1991) 94 Cr App Rep 367 the accused believed that her partner was about to kill her since he had a history of previously abusing her. The Court of Appeal held that provided the accused had acted under an honest mistake of fact a trial judge should direct a jury on whether her response was commensurate with the attack which she believed she faced.

In Williams (Gladstone) [1987] 3 All ER 411 the accused believed that he was witnessing a person being assaulted, whereas in fact, the person was being lawfully arrested. The accused intervened and in so doing attacked the man making the arrest. At his trial, the accused said that he intended only to use lawful force to prevent what he thought was a crime from being committed. The Court of Appeal quashed his conviction holding that he was to be judged on the facts as he honestly believed them to be whether or not that belief was a reasonably held one. As Lord Lane CJ pointed out at p415: 

The decision in Williams (Gladstone) was approved by the Privy Council in Beckford v The Queen [1988] AC 130 and has now also been placed in statutory form by the enactment of the Criminal Justice and Immigration Act 2008, sections 76(4)-(7).

In Yaman & Anr [2012] EWCA Crim 1075 one of the owners of a late-night kebab shop was driving past his premises one morning and saw the shutters were raised. He entered the shop and struck the victim over the head with a hammer. In fact, the victim was a locksmith who had lawfully entered the premises with a warrant officer and gas engineer to execute a warrant following alleged non-payment of gas bills. The accused was convicted of wounding with intent to do grievous bodily harm and appealed on the basis that the trial judge had failed to direct the jury in accordance with section 76(7)(b) of the 2008 Act. The Court of Appeal dismissed his appeal and held that even if one were to assume that in attacking the locksmith with the hammer the accused had mistakenly "done what he honestly and instinctively thought was necessary" to repel what he thought was a burglary the jury would still have inevitably concluded that the force he used was excessive and had therefore used more force than was reasonable in the circumstances. Even though the trial judge's directions to the jury were defective they were not fatal to the accused's conviction.

The exception to the rule that a mistaken belief need not be reasonably held is in relation to agents of the state. It was held in Caraher v United Kingdom (2000) 29 EHRR CD119 that mistakes made by agents of the state must be based on both honest and reasonable grounds so as not to violate the European Convention on Human Rights.

Williams (Gladstone) is a criminal case. In civil cases, any mistake must be both honestly held and reasonable: see, Ashley & Another v Chief Constable of Sussex Police, below.

However, if the accused's mistaken belief arises out of his own voluntary intoxication, he will not be permitted to rely on the mistake in his defence. The following case illustrates this position clearly.

In O'Grady [1987] 3 WLR 321 the accused had been drinking with the deceased and they returned to his flat where they both fell asleep. The accused was awoken by blows to his head by the deceased, and retaliated with what he considered to be a few mild blows, after which he fell asleep again. When he later awoke, he found the body of the deceased who had died as a result of his blows. At his trial, he claimed that because he was drunk, he had mistaken the amount of force he needed to protect himself from the deceased's assault. The trial judge directed the jury that the accused was entitled to rely on the defence of self defence, and that he was to be judged on the facts as he believed them to be, but added that he was not entitled to go beyond what was reasonable by way of self defence and the fact that he might have mistakenly exceeded this position because he was drunk, did not afford him a defence. His conviction was upheld on appeal. Lord Lane CJ said that where the mistaken belief as to the amount of force needed to defend himself arose because of self-induced intoxication the defence of mistake would not be available.

The principles from O'Grady were subsequently applied by the Court of Appeal in Hatton [2005] EWCA Crim 2951 where the accused had been charged with murder after beating the victim to death with a sledgehammer. It was suggested at trial that because he was drunk he may have believed that the victim was attacking him with a sword. The judge ruled that a drunken mistake as to the need to use force to defend himself was no defence and this ruling was confirmed as correct by the Court of Appeal.

Finally, mention should be made to cases where the accused applies force to either a police officer or officer of the court which would be reasonable if that person were not a police officer or officer of the court and the accused honestly believed that that person was not such an officer. In these circumstances, it was held by the Court of Appeal in the civil case of Blackburn v Bowering [1994] 3 All ER 380 that provided the accused's belief was honestly held he will be able to avail himself of the defence of self defence even if his belief was unreasonably held.

The threatened harm must be imminent, although the response need not be spontaneous.

The law permits a person to prepare to repel an attack. In Attorney-General's Reference (No.2 of 1983) [1984] QB 456 the accused had produced and kept in his shop petrol bombs at a time when there was extensive rioting in the area. The Court of Appeal held that there was evidence on which the jury might have decided that the use of the petrol bombs would have constituted reasonable force in self defence against an attack and, if so, the accused would have had the petrol bombs for "a lawful object". The Court of Appeal emphasised the need for any threat to be imminent. This position was confirmed by Lord Griffiths in Beckford v The Queen [1988] AC 130 (Privy Council).

The accused must not have deliberately provoked or created the situation for which he intends to rely on the defence.

The defence of self defence will fail where the accused intentionally provoked the attack so as to kill or otherwise injure, purportedly in self defence. In the Northern Irish case of Browne [1973] NI 96 Lowry LCJ stated:

In Malnick [1989] Crim LR 451 the accused was travelling to see a man whom he believed to be in possession of stolen vehicles belonging to his friend. He understood that this person was violent and, for this reason, took with him a martial arts weapon known as a rice-flail. He was arrested before he reached the other person's property. His claim that since he feared attack he was justified in carrying the rice-flail was rejected on the ground that the danger was of his own making.

The Court of Appeal pointed out in Rashford (Nicholas) [2006] Crim LR 547 that a person may still plead self-defence in a case where he killed another during an argument which he himself started, either by provoking it or willingly entering into it, and the other person then retaliated. The mere fact that a defendant went somewhere to exact revenge from the victim did not of itself rule out the possibility that in any violence that ensued self defence was necessarily unavailable as a defence.

Similarly, in Keane; McGrath [2010] EWCA Crim 2514 the Court of Appeal ruled that just because a defendant had either started the fight with the victim or entered it willingly, he was not barred from raising self defence as a defence at his trial. Thus, self defence could arise in the case of the original aggressor, but only where the violence offered by the victim was so out of proportion to what the original aggressor did that the roles were in effect reversed. The Appeal Court in Keane; McGrath also confirmed that there was no law which stated that if a defendant set out to provoke another to punch him, and succeeded, then the defendant was entitled to punch the other person.

The accused aims a blow at X but inadvertently injures Y.

A situation might arise where a person aims a blow at X but misses his intended target and instead injures Y who is an innocent bystander. The law relating to this kind of situation is known as “transferred malice”. This is perhaps an unfortunate term since it might suggest that the accused has acted with malice although this is not a requirement for a person to be convicted.

In Latimer (1886) 17 QBD 359 the accused aimed a blow at his intended target which glanced off him and struck another person who was standing nearby causing her serious injury. The court held that Latimer could be convicted of maliciously wounding the woman on the grounds that his intention was to injure and that it was not relevant that the victim was not his intended target.

The position is, however, different where a person acts with the mens rea (guilty mind) of one offence but commits the actus reus (physical act) of different offence except in circumstances where the offence in question is one where the mens rea can be satisfied with recklessness and the accused was reckless as to the risk of the kind of harm he actually caused. An example of this type of situation can be seen from Pembliton (1874) LR 2 CCR 119 where the accused, who had been fighting with others in the street, threw a stone at them which missed and instead smashed a window in a nearby public house. His appeal against conviction for maliciously damaging the window was allowed because he had acted with the intention of injuring persons and not with the intention of damaging property. The court observed that had the jury found that Pembliton had been reckless as to the risk of damaging property then his conviction would have been upheld because recklessness was a sufficient mens rea for the offence charged.

Can an attack on an innocent third party ever constitute self defence?

The consequences of a person's actions were unexplained.

It was held by the Court of Appeal in Attorney-General's Reference (No.2 of 1983) [1984] QB 456 that it is irrelevant if the consequences of an accused’s actions were unexpected. Therefore, if the accused shoots his victim intending to kill him but the bullet misses and instead strikes a box of fireworks nearby which sets off an explosion that kills the victim, it is wholly irrelevant that his victim is killed by the resulting explosion rather than the intended bullet.

The Human Rights Act 1998/European Convention on Human Rights.

Article 2 of the European Convention on Human Rights provides:

(a) in defence of any person from unlawful violence;

(b) in order to effect a lawful arrest or to prevent escape of a person lawfully detained;

(c) in action lawfully taken for the purpose of quelling a riot or insurrection.

Where a person uses reasonable force to defend himself, and in so doing kills his attacker, the attacker’s right to life under Article 2 will not have been infringed because the attacker’s initial act of aggression will have negated this right. If excessive force has been used then Article 2 may have been infringed.

It was noted above that the rule in Williams (Gladstone) entitles a person to be acquitted where he has used reasonable force but was mistaken as to the need to use that force. Such a person may nevertheless have infringed Article 2 because under ECHR law any such mistake must be reasonable, objectively assessed, rather than just honestly and maybe unreasonably made, which is subjectively assessed under the rule in Williams (Gladstone).

This presents a potential conflict between English law and that laid down by the ECHR and there are arguments that English law is incompatible with the European Court of Human Rights’ jurisprudence. The main thrust of these arguments of incompatibility are that a person’s right to life (under Article 2) cannot be sufficiently protected if he may be killed by force that has been used against him without reasonable grounds for so doing. Article 2 allows for a life to be taken only where “absolutely necessary”. Under English law, a person may be acquitted of murder even where his use of force was completely unnecessary.

In one of the leading cases decided by the European Court of Human Rights, McCann v UK (1996) 21 EHRR 95, the Court said that an accused needed to have “good grounds” to use force. These words imply an objective test whereas English law sets this test as subjective: Williams (Gladstone), requiring only that the defendant’s use of force was based on a genuine belief. However, Article 2 does not appear to demand a change to English law on this point and in Bubbins v UK (2005) 41 EHRR 458 the Court refused to condemn the English subjective approach to this test and stated that the defendant held “an honest belief which was perceived for good reason to be valid at the time but which was mistaken”.

As yet, there has been no English case before the ECHR where a person has killed another based on a wholly irrational mistake and if such a case arose then the ECHR may well have to deal with this incompatibility. However, the (English) Court of Appeal has recently upheld the decision of Collins J in R (Bennett) v HM Coroner for Inner London [2007] EWCA Civ 617, a case concerning a judicial review of a coroner's decision. A person was killed after being shot by a police officer. A witness had given evidence that the deceased was carrying a gun and that two firearms officers were present. In 30 seconds, one of the firearms officers had fired six shots, four of which struck the deceased in his back and side and one of which proved fatal. The coroner refused to leave to the jury a verdict of unlawful killing. The jury then returned a verdict of lawful killing. The application for judicial review was on the grounds that the coroner's direction to the jury on self defence had disregarded Article 2.

Collins J stated that "the European Court of Human Rights has considered what English law requires for self defence, and has not suggested that there is any incompatibility with Article 2. In truth, if any officer reasonably decides that he must use lethal force, it will inevitably be because it is absolutely necessary to do so. To kill when it is not absolutely necessary to do so is surely to act unreasonably. Thus, the reasonableness test does not in truth differ from the Article 2 test as applied in McCann.”

It should be noted that Article 2 is more restrictive than English law where a person may be acquitted where he has killed another person in response to an attack on property (see, for example, Hussey (1924) 18 Cr App Rep 160, above). It can be seen from the wording of Article 2 that the position would be different under the ECHR.

Articles 3 (freedom from torture and inhuman and degrading treatment) and 5 (right to liberty) also need considering. In Rivas v France [2004] ECHR 131 the European Court of Human Rights stated that these rights are subject to implied exceptions in cases where a person's injuries have been inflicted in self defence. It follows, therefore, that a person will not infringe another's Article 5 rights by restraining and detaining him to prevent a further unlawful attack.

Self-defence weapons.

The law does not recognise the concept of a "defensive weapon". You are not permitted to carry an offensive weapon - even to defend yourself. You may, however, provided it constitutes reasonable force, defend yourself with an ordinary everyday object, such as keys, an umbrella or a comb, provided you have them with you for their ordinary everyday purpose.

The consequences of using excessive force - an 'all or nothing' defence.

If the Court finds that the accused has used excessive force then his defence of self defence will fail and he will be guilty of the offence charged. If he has killed the other person, supposedly in "self defence", and has been charged with murder and the Court finds that he has used excessive force, his conviction will not be reduced to manslaughter and he will be guilty of murder, provided the Court is satisfied that he intended to kill or cause serious bodily harm from which the death resulted.

This was seen in the case of Clegg [1995] 1 All ER 334 where the accused, a soldier on duty in Northern Ireland fired four shots at a car (later known to be stolen) which failed to stop at a checkpoint. The Court accepted that the first three shots were fired either in self defence or in defence of the accused's colleagues, but the fourth, which killed a joyrider in the car, was not so fired on the ground that the car had by then passed the checkpoint by some 50 feet. The House of Lords upheld the accused's conviction for murder. It made no difference that the force had been used in the prevention of crime or arresting an offender or that the accused was a soldier or police officer acting in the course of his duty.

Loss of Control - a partial defence.

On 4^th October 2010 a new defence was introduced into law by section 54 of the Coroners and Justice Act 2009. This defence, abolishing the old defence of provocation, is referred to as a “loss of control” and prioritises the emotion of fear as a justification for killing. As with the old law of provocation, it applies only in circumstances where the accused has killed another person. There are three key elements to this defence:

1.    a loss of control; 

2.    a qualifying trigger; and

3.    a requirement that a reasonable person, of the accused's sex and age, with a normal degree of tolerance and self-restraint, finding himself in the circumstances of the accused, would have reacted in the way that the accused acted

If sufficient evidence is adduced to raise an issue with respect to this defence, the jury must assume that the defence is satisfied unless the prosecution proves (beyond reasonable doubt) that it is not (section 54(5)).

Unlike the law of self-defence which, if successful, provides a complete defence to the charge, this defence, if successful, is only a partial defence and will mean that the accused is not guilty of murder but guilty of manslaughter.

In order for this defence to apply, the accused must have lost their self-control at the time of the killing. The loss of self-control need not be sudden (section 54(2)) although any delay could be construed as evidence that the accused had not actually lost his self-control but acted out of revenge. The defence will not apply to any killing consequent upon a considered desire for revenge (section 54(4)).

The “qualifying trigger” noted above is defined in section 55 and includes where the accused’s loss of self-control was attributable:

1.    to his fear of serious violence from the deceased either against himself or another identified person – but not against an unidentified group of people (section 55(3))

2.    to a thing or things done or said which constituted circumstances of an extremely grave character and caused the accused to have a justifiable sense of being seriously wronged (section 55(4))

3.    to a combination of the above (section 55(5))

It can be seen, therefore, that the defence will be available in circumstances where there is fear and where there is anger. This was partly justified by the Law Commission which pointed out that there is evidence that fear and anger are not distinct emotions but are frequently seen together in acts of violence.

The “fear of serious violence” as noted in section 55(3) could be used in cases of self defence or where the accused kills a person burgling his home. In cases of self defence, the defence could be used even in cases where the defence of self defence could not be used, for example, because the accused’s reaction is deemed to have been disproportionate or where there was no imminent threat from the deceased. This is an important point because it provides a partial defence and thus avoids the “all or nothing” approach of self defence. The qualifying trigger of a fear of serious violence from the deceased will be assessed subjectively. There is no requirement, therefore, that this fear be reasonable: it only needs to be honestly held.

Interrelationship with civil law.

Even in circumstances where the accused has a defence of self defence to a criminal charge, he may still be held liable in the tort of negligence in respect of the same act: Revill v Newbery [1996] 2 WLR 239. Thus, where an occupier of premises comes across a burglar on his land he cannot act with total disregard to the burglar's safety and the maxim ex turpi causa non oritur actio ("from a dishonourable cause an action does not arise") cannot be invoked to provide the occupier with what would amount to a complete defence to the burglar's claim for damages. However, even though such a complete defence may not be available to the occupier, the courts are likely to reduce the amount of the claimant's award on the ground of contributory negligence: Revill v Newbery [1996] 2 WLR 239 (where the damages awarded to the claimant were reduced by two-thirds).

A further distinction between the civil and criminal law was recently explained by the House of Lords in Ashley & Another v Chief Constable of Sussex Police [2008] UKHL 25. One of the issues for determination was whether a plea of self defence to a civil law claim for assault and battery (trespass to the person) in a case where the assailant acted in the mistaken belief that he was in imminent danger of being attacked requires that the assailant acted under a mistaken belief that was not only honestly but also reasonably held.

It will be recalled that the Court of Appeal in the criminal case of Williams (Gladstone) held that the mistake must be honestly, although not necessarily reasonably, held (see above). In Ashley, the House of Lords confirmed the correctness of this decision insofar as it relates to a criminal trial but held that where self defence is at issue in a civil action the position is that “the necessity to take action in response to an attack or imminent attack must be judged on the facts as the defendant honestly believed them to be, whether or not he was mistaken, but, if he made a mistake of fact, he can rely on that fact only if the mistake was a reasonable one for him to have made”, per Lord Scott.

The House of Lords rejected the argument that the criteria for self defence in civil law should be the same as for criminal law because “the ends to be served by the two systems are very different”. Lord Scott stated that "To hold, in a civil case, that a mistaken and unreasonably held belief by A that he was about to be attacked by B justified a pre-emptive attack in believed self defence by A on B would, in my opinion, constitute a wholly unacceptable striking of the balance. It is one thing to say that if A's mistaken belief was honestly held he should not be punished by the criminal law. It would be quite another to say that A's unreasonably held mistaken belief would be sufficient to justify the law in setting aside B's right not to be subjected to physical violence by A. I would have no hesitation whatever in holding that for civil law purposes an excuse of self defence based on non-existent facts that are honestly but unreasonably believed to exist must fail".