The defence of insanity

The cases of Anders Breivik (who shot 69 people on Utoya Island in Norway) and James Holmes (who shot 12 people in a cinema in Aurora, Colorado) raise again the issue of when a criminal defendant should be able to take advantage of a defence of insanity. As laid down in the M’Naghten Rules (‘MR’, for short), the defence of insanity will be available to a defendant if, at the time he acted, he was ‘labouring under such a defect of reason, from a disease of the mind, as not to know the nature and quality of the act he was doing; or if he did know it, that he did not know what he was doing was wrong.’

One criticism that it is often made of the defence of insanity is that it is medically outdated – that our notions of when someone can be said to have been medically insane in acting as he did have developed since 1843, when the MR were laid down, and the law has failed to keep pace with those developments. However, this criticism is unjustified: in my view, the MR are not intended at all to reflect clinical or medical ideas as to when someone should be said to be insane.

Instead, I think the MR are directed at identifying cases where: (1) it was impossible for the defendant to alter his conduct to make it conform to the law (which accounts for the requirement that the defendant must not have known what he was doing or must not have known that what he was doing was wrong), and (2) the defendant was unable to alter his conduct to make it conform to the law because he suffered from an internal condition which means that the defendant is likely to do what he did again, and therefore constitutes a public danger that needs to be dealt with (which accounts for the requirement that the defendant’s incapacity arises out of a ‘disease of the mind’).

On this view, then, the MR are not at all concerned to reflect modern medical notions of when someone can be said to be insane: they arise out of a dual concern to uphold the requirements of the rule of law – which would dictate that someone not be held liable for breaking the law if he was incapable of being guided by its dictates – and to ensure that people who get the treatment they need to deal with conditions that they have that, if unaddressed, will prevent them from complying with the law in the future.

So it really does not matter whether Breivik or Holmes were medically insane when they acted as they did (which they probably were). They were both clearly capable of conforming their conduct to the law, and as such can be properly held accountable for their failures to exercise that capacity. If – having been imprisoned for their crimes – they also require medical treatment to deal with their psychiatric conditions (as Peter Sutcliffe, the Yorkshire Ripper, did, eventually being incarcerated in Broadmoor Hospital under the Mental Health Act 1983) then they should receive it; but their psychiatric states cannot excuse them from being punished for their failures to obey the law.

All of this is not to say that the law on when someone will be found not guilty by reason of insanity is perfect. Four criticisms of the law can be made.

(1) Stigma. There is a concern that defendants who fall within the MR might be put off pleading that they are ‘not guilty by reason of insanity’ because of the stigma attached to being labelled as ‘insane’. This concern gets particularly strong in cases like Sullivan (epilepsy) and Hennessy (diabetes) where what triggered the defendant’s incapacity to comply with the law was an internal condition that no one would ordinarily categorise as ‘insanity’. If the MR are really not concerned with medical notions of insanity, there is a case for saying that we should not use the term ‘insanity’ to refer to the defence to which the MR apply. However, it is difficult to think of what alternative name we could give this alternative defence. ‘Not guilty by reason of internal incapacity’ feels a bit too clinical.

(2) Civil liberties. Another reason why defendants might be unwilling to plead ‘not guilty by reason of insanity’ is that if the plea is successful, then the court is then empowered under s 3 of the Criminal Procedure (Insanity and Unfitness to Plead) Act 1991 to make an order requiring the defendant to be restrained in hospital for an ‘unlimited period of time’. Now – the court does not have to make such an order (though it does in the case where the sentence for the offence which the defendant was charged with is fixed by law (effectively, murder cases)) – it could make a more limited order, or even an absolute discharge. But the possibility that a court might make such an order in their case would make a defendant – particularly one who is charged with a relatively petty offence such as shoplifting – hesitate long and hard before making a plea of ‘not guilty by reason of insanity’ for fear of being trapped in a One Flew Over the Cuckoo’s Nest situation of being trapped in an institution where you are not insane, but are treated as though you are, and are eventually driven crazy by the experience. One way of getting round this problem would be to amend the 1991 Act to require a defendant who has been committed to hospital having pleaded ‘not guilty by reason of insanity’ to appear before a judge at regular intervals so that the judge (preferably the one who presided over the defendant’s trial) can evaluate their treatment and condition and ensure that they are not being treated inappropriately.

(3) Falling between two stools? The defence of ‘not guilty by reason of insanity’ exists alongside the ‘defence’ of non-insane automatism – which is not really a defence, but a denial that the defendant committed the actus reus of the crime because an external cause (for which the defendant was not at fault) meant that the defendant was unaware of what he was doing (the defendant ‘blacked out’) or was aware of what he was doing, but was unable to control his bodily movements (the defendant was acting reflexively). However, there may be one situation which falls between these two defences, because it does not come under either of them. This is the situation where due to an external cause (for which the defendant was not at fault) the defendant thinks that there is nothing wrong – either legally or morally – with acting in a particular way, and he goes on to act in that way, where acting in that way amounts to the actus reus of an offence. For example: D is hit on the head by a stone. When he comes to, he thinks that he is the emperor of the world, and that all women are required to have sex with him, if he so wishes. He proceeds to have sex with V against her will. D won’t be able to rely on a defence of non-insane automatism because he was not acting as an automaton in having sex with V – he knew what he was doing, and was in control of his body. But will he be able to take advantage of a defence of ‘not guilty by reason of insanity’? The difficulty is that his delusions were triggered by an external cause – that of being hit on the head by a rock. Perhaps it could be argued that the external cause triggered a ‘disease of the mind’ and in that way allow him to take advantage of the defence of insanity. But this seems hard to reconcile with cases like Bailey, where the defendant acted under the influence of an insulin injection, and was held not to be able to take advantage of the defence of insanity. (Though it looks like the defendant knew what he was doing in that case – though he might not have been aware of the effects of his actions.)

(4) Strict liability. In DPP v Harper, the Court of Appeal ruled that the defence of insanity did not apply to strict liability offences – in that case, driving with excess alcohol in one’s bloodstream. This seems wrong. If the MR are directed at someone’s being unable to conform their conduct to the law, then there seems no reason why they should not apply as much to strict liability offences as they do to offences which require some degree of mens rea for their commission. A defendant who seeks to take advantage of the MR is not denying that he had the mens rea for the offence with which he is charged: he is making a much more basic point – that he should not be held responsible for his actions because they were either not his actions or they were performed in ignorance of the fact that they might be contrary to the law (and he was not at fault for that ignorance – so the maxim ignorantia legis non excusat does not apply). (Having said that, there are a couple of cases which suggest that a strict liability offence will capture someone who was completely incapable of avoiding committing that offence, and on that basis they refused to find that the offence in question was a strict liability offence. They are Sherras v De Rutzen (refusing to find that the offence of selling alcohol to an on-duty policeman was a strict liability offence as it would be impossible for someone selling alcohol to know whether a policeman was on-duty or off) and Lim Chin Aik v R (refusing to find that the offence of entering Singapore when having been prohibited from doing so was a strict liability offence as the notices prohibiting someone from entering Singapore were only published in Singapore, and so it would be impossible for someone outside Singapore to know whether they were prohibited from entering Singapore). These cases may be confusing absolute liability – where it is no defence to say ‘It was impossible for me to avoid the prohibited conduct’ – and strict liability, where in principle it should be a defence to say that it was impossible to avoid doing the thing which is prohibited.)

The law on intoxication

The basic point

There is no such thing as a defence of intoxication under the criminal law. If you ever find yourself writing ‘D may be able to take advantage of a defence of intoxication’ you are doing something very, very wrong. You need to stop and think – why am I saying this?

Intoxication is only relevant to whether or not a defendant has committed a criminal offence if it means: (1) he did not commit the actus reus of the offence; or (2) he did not have the mens rea for the offence; or (3) he mistakenly believed in facts which, if true, would mean he had a defence to being found guilty of committing that offence. If none of (1), (2) or (3) apply, then the defendant is guilty – the fact that he acted in an intoxicated state will be completely irrelevant.

Kingston illustrates the point. Defendant’s drink was spiked, his inhibitions were consequently loosened, and he ended up sexually assaulting a boy. He knew what he was doing at the time and was in control of his body. He was found guilty: he had the actus reus of the offence (unconsented to touching of a sexual nature), he has the mens rea (intention to touch, or recklessness as to touching) and was not acting under a belief which, if true, would have given him a defence. The fact that the defendant would not have acted as he did had his drink not been spiked was irrelevant. He was still responsible for his actions. If I offered you a million pounds to kill your best friend, and you took the money and killed your best friend, you could not dream of trying to get off the charge by arguing, ‘Had I not been offered the money, I would never have killed my best friend.’ And yet people still try to argue that Kingston should have been acquitted. Whatever it was that caused you to loosen your inhibitions – money, drugs, drink, lust – if you are still responsible for your actions, you can still be held accountable for them under the criminal law.

Let’s now look at how the law handles cases when a defendant can argue that either (1), (2) or (3), above, apply.

No actus reus

In this sort of case, the effect of D’s intoxication either means that D had no idea what he was doing, or D was not in control of his body. In either case, D might be able to argue: I didn’t have the actus reus because I didn’t cause whatever harm it is that my body did while I was blacked out or had no control over my body’s physical movements. If this argument works, then D is entitled to be acquitted on the basis of non-insane automatism (not insane automatism, because the automatism had an external cause – the intoxication). But there is one exception. If D was responsible for his own intoxication then we can say (at least where the actus reus of the offence requires that it be shown that D caused a particular harm) that D did have the actus reus. By causing himself to get drunk, he was the ultimate cause of the harm that his body did while D was blacked out or not in control of his body’s physical movements. So we can contrast two cases:

Wild Thing 1. D gets so drunk in a pub that he ends up having convulsions. As he is flailing around, one of his fists hits a fellow drinker, V. In this case D has the actus reus of assault occasioning actual bodily harm (assuming that the hit did abh to V). D  ultimately caused his fist to touch V by getting so drunk that he went into convulsions, and this caused (we are supposing) V to suffer actual bodily harm.

Wild Thing 2. Same as Wild Thing 1 except D was drinking what he thought was orange juice, but it had been spiked by T. In this case, D does not have the actus reus for assault occasioning actual bodily harm because he did not cause his fist to hit V. T did that; so if anyone is going to be guilty of assault occasioning actual bodily harm, it should be T. But D is entitled to be acquitted here on the basis of non-insane automatism.

No mens rea

In this sort of case, the effect of D’s intoxication means that D can deny that he had the mens rea for the offence with which he has been charged. For example, if, say, he was charged with murder, D would be arguing – my intoxicated state means that I did not have an intent to kill or an intent to cause gbh. If, on the other hand, he was charged with malicious wounding, D would be arguing – I did not appreciate that there was an unreaonable risk that V would suffer some physical harm from my actions. Here are a couple of situations where D would be able to make such an argument:

Polar Bear. D gets blind drunk in a pub. As he walks outside the pub, alone, he sees what he thinks is a polar bear coming towards him. (In fact, it is V, dressed in a white parka.) Thinking that the polar bear’s head would look great on his wall, D grabs hold of what he thinks is the polar bear and cuts its head off with a handy knife. On sobering up, D is told that he decapitated V and is being charged with murder. D has the actus reus for murder: he caused V’s death by sawing V’s head off. But D will argue that he did not have the mens rea for murder when he was sawing V’s head off: he intended to kill a polar bear, not a human life in being.

Note that this argument would not work if D was getting blind drunk in order to get up the courage to go home and kill his wife. In such a case, we could dial back the moment when D caused V’s death to the moment when he was getting drunk in the pub, and say that that act of getting drunk caused V’s death because V would not have died had D not gotten blind drunk, and there was no obvious break in the chain of causation after the moment he got drunk to break the chain between the getting drunk and V’s dying. And at the moment D got drunk, he did have an intent to kill – he was getting drunk with the aim or purpose of killing his wife. So in that situation, D would not be able to deny that he had the mens rea for murder, contemporaneous with the actus reus, and would consequently be convicted of murder. This is known as the ‘Dutch courage rule’ (first articulated by Lord Denning in Attorney-General for Northern Ireland v Gallagher).

But let’s assume the ‘Dutch courage rule’ doesn’t apply in Polar Bear: D was getting drunk just for the hell of it. In such a case, D would argue that he should be acquitted because he did not have the mens rea for murder.

Darts. D gets blind drunk in a pub. He gets up, intending to have a game of darts. But he is so drunk, he thinks that the darts in his hand are actually little wriggling mice. He is so disgusted, he throws one of the ‘mice’ at a nearby drinker, V, shouting, ‘Look at this! That’s horrible!’ When D sobers up, he is told that V was actually struck in the eye by the dart that he threw at V, and that D is going to be charged with malicious wounding, contrary to s 20 of the Offences Against the Person Act 1861. D has the actus reus: what he did in throwing the ‘mouse’ at V caused V to be wounded. But D will argue that he did not have the mens rea: when he threw the ‘mouse’ at V, he did not foresee that V would suffer ‘some kind of physical harm’ as a result of his actions.

In cases where D seeks to rely on his own intoxicated state in order to deny that he had the mens rea of the offence with which he has been charged, a very simple rule (called the Majewski rule) applies to determine whether D can do this. In the case where D was to blame for getting drunk, the courts ask – Had D not been drunk, would he have had the mens rea for the offence with which he has been charged? If the answer is ‘yes’ then D will not be allowed to deny that he had the mens rea for the offence with which he has been charged. If the answer is ‘no’, then D will be allowed to persist in his plea that he did not have the mens rea for the offence with which he has been charged, and will be acquitted on the basis of no mens rea.

Let’s see how the Majewski rule would apply in our two situations:

Polar Bear. Here D’s drunken state means that he did not have the mens rea for murder, but he was also to blame for getting drunk, so we might prevent him denying that he had the mens rea for murder depending on the application of the Majewski rule. So we ask – Had D not been drunk, would he have had an intent to kill or an intent to cause gbh? The answer, pretty obviously, is ‘no’ so D is allowed to persist in his plea that he did not have the mens rea for murder and will be acquitted on the basis of no mens rea.

Darts. Here D’s drunken state means that he did not have the mens rea for malicious wounding, but he was also to blame for getting drunk, so we might prevent him denying that he had the mens rea for malicious wounding depending on the application of the Majewski rule. So we ask – Had D not been drunk, would he have foreseen that there was a risk of V suffering some kind of physical harm when he acted as he did? Well, had D not been drunk, he would have realised he was holding a dart, not a mouse, so he plainly would have foreseen that there was a risk of V suffering some kind of physical harm when he threw the dart at V. So the answer to our question is ‘yes’ and as a result D will not be allowed to deny that he had the mens rea for malicious wounding. As a result, D will be convicted of malicious wounding – he committed the actus reus, and is not allowed to deny that he had the mens rea, and will have no relevant defence.

The textbooks try to sum up the above by saying that a defendant who is charged with a criminal offence will – if he was to blame for getting drunk – be allowed to rely on his drunken state to deny that he had the mens rea for the offence if the offence was one of ‘specific intent’ (= mens rea requires an intent to produce a particular outcome), but not if the offence was one of ‘basic intent’ (= mens rea can be established merely by showing that the defendant foresaw that his actions would have a particular outcome). But this is dangerously vague. It would be better just to ask, in a case where the defendant seeks to rely on his drunken state to establish that he did not have the mens rea for the offence with which he has been charged, and the defendant was to blame for getting drunk, the Majewski question: Would the defendant have had the mens rea had he not been drunk? Answering that question will allow you to determine whether or not the defendant will be allowed to deny that he had the mens rea without having to worry about whether the offence that the defendant has been charged with is one of ‘specific intent’ or ‘basic intent’.

Mistaken belief in defence

In this sort of case, D’s intoxicated state means that he believed facts were true, that if they were true would have given him a defence, such as self-defence, or duress. Examples:

Banana Man. D is high on LSD. In his drunken state, he believes V is running towards him with a knife, and is about to stab him. D takes out a gun and shoots V dead. In fact, V was not holding a knife but a banana, which he was urging D to eat.

Down at Heel. D is in the pub with V. V is telling D about his financial problems, and says to D, ‘You’ll take care of me, won’t you? You’d really regret it if you didn’t.’ D is pretty drunk and misinterprets V as threatening that he will kill D unless D immediately gives him money. D pulls out a gun and holds up the pub, netting £2,000, which he instantly hands over to an astonished V.

In these cases, the courts ask a very simple question – Was D to blame for his intoxicated state? If he was, then he will not be allowed to rely on his mistaken belief to argue that he has a defence. But if he was not to blame for being intoxicated, and if the facts that D’s intoxicated state led him to believe were true would – if true – have given him a defence, then D will be allowed to raise that defence to the offence with which he has been charged.

So if, in Banana Man, someone had slipped D a tab of LSD without his realising it, and shooting V would have been a reasonable thing to do had V actually been about to knife D, then D will be acquitted of murder on the ground of self-defence. (Note that in Banana Man, the fact that D had the actus reus and mens rea for murder is easily established.) But if in Banana Man, D had taken the LSD, he will not be allowed to rely on his mistaken belief to argue that he should be acquitted on the ground of self-defence. (Note that this is an exception to the normal approach, established in Gladstone Williams, that a defendant will be entitled to raise a defence of self-defence so long as he honestly believed in facts that, if true, would have given him a defence of self-defence.)

The same is true in Down at Heel. If D was to blame for getting drunk, he will not be allowed to rely on a defence of duress when he is charged with theft. But if someone had been spiking his orange juice, he will be allowed to rely on his mistaken belief that V was threatening to kill him to set up a defence of duress. (This is assuming that on the facts that he believed to be true he would have had a defence of duress.)

The one case where a defendant who was to blame for getting drunk will still be allowed to rely on a mistaken belief in facts which, if true, would have given her a defence was established in Jaggard v Dickinson. Under s 5(2) of the Criminal Damage Act 1971, it is a defence to being convicted of causing criminal damage to property belonging to another if you believed the owner of the property would have consented to the damage. The defendant, in a drunken state that she was to blame for getting into, attempted to break into her friend’s house believing that her friend would be happy for her to do this. In fact, she had got the wrong house and was breaking down someone else’s door. She was acquitted of criminal damage to property on the basis that she honestly believed that the owner of the door would have been happy for her to break down the door. This was so even though the only reason she thought this was because she was drunk, and she was to blame for getting drunk.

Criticisms of the law

The law on intoxication is sometimes criticised on the basis that –

(1) It is unclear.

(2) It does not provide a defence to someone like the defendant in Kingston.

I don’t think either of these criticisms are justified. The law is pretty clear (as you can see from my summary above), and there is no way the law should be acquitting the defendant in Kingston. But this does not mean that the law in this area is beyond criticism. Two criticisms can be made:

(3) In Darts we end up convicting the defendant of a very serious offence – malicious wounding – simply on the basis that he was to blame for getting drunk. This does not seem right. If the defendant, when he got drunk, did not foresee the risk of other people coming to some physical harm as a result, he is being found guilty of an offence for which such foresight is required when he had no such foresight. He is being found guilty because he is prevented, under the Majewski rule, from denying that he had such foresight. Convicting someone on the basis of a fiction seems very unsatisfactory. It looks like the defendant in Darts is being convicted on a constructive basis – he did something bad when he got drunk, and then the offence he ends up being convicted of depends on the level of harm that resulted from his getting drunk without any requirement that he needs to have foreseen that harm.

(4) The workings of the above rules seems to produce some arbitrary results. Consider:

Tramp 1. Two tramps, Vladimir and Estragon, get very drunk and take a lot of drugs and fall asleep near each other. Vladimir wakes up, still intoxicated, and thinks that the sleeping Estragon beside him is a writhing mass of snakes that are about to attack him. Vladimir panics, pours the remaining alcohol near him onto Estragon and sets it on fire. Estragon dies. Vladimir is charged with murder but is acquitted on the basis that he lacked the mens rea for murder: he did not have an intent to kill a life in being. See R v Lipman.

Tramp 2. The same facts as Tramp 1, but in this case when Vladimir wakes up, he wrongly thinks that Estragon is attacking him with a knife. Vladimir strangles Estragon. Vladimir is charged with murder and is convicted on the basis that he had the actus reus for murder (he caused Estragon’s death), and the mens rea for murder (he intended to kill Estragon), and he can’t rely on his mistaken belief that he thought that Estragon was attacking him because that mistaken belief was the result of his intoxicated state, and he was to blame for being intoxicated. See R v O’Grady; R v Hatton.

But what, morally, is the difference between Tramp 1 and Tramp 2 that would justify us in acquitting Tramp 1 of murder, and finding Tramp 2 guilty? The treatment of Tramp 2 looks even more arbitrary given the fact that under Gladstone Williams a non-intoxicated but still stupid belief that one is about to be attacked might entitle a defendant to be acquitted of murder.

The defence of necessity

What is it?

A defendant seeks to rely on a necessity-type defence when he argues that he should not be convicted of a criminal offence because his conduct was justified, and it was justified because he did more good than harm in acting as he did.

Defences that are not necessity defences

Given this definition, two defences that are often categorised as being instances of an overarching defence of ‘necessity’ actually having nothing to do with necessity, properly understood.

(1) Duress

The defence of duress – which is available to a defendant who acted under the pressure created by the need to avoid death or serious injury to himself or to someone for whom he is responsible – cannot be analysed as a necessity defence because a defendant seeking to raise a defence of duress is not seeking to justify his conduct. Instead he is seeking to excuse his conduct by arguing, in essence, that ‘I know what I did was wrong, but I acted as I did under pressure that would have led a normal person to act in the same way as I did. So it’s unfair to find me guilty of committing an offence here because had you been in the same position as me, you would have done the same as me. So it’s just an arbitrary accident of fate that had led me rather than you to end up being charged with this offence, and we shouldn’t allow arbitrary accidents of fate to determine people’s criminal guilt.’

(2) Self-defence

The defence of self-defence is often analysed as being a form of necessity defence because: (1) a defendant who seeks to rely on the defence of self-defence is seeking to show that his conduct was justified, just as he would be doing if he were seeking to rely on a defence of necessity; and (2) a defendant who seeks to rely on the defence of self-defence will not be allowed to rely on the defence unless he used reasonable force to defend himself given the facts as he believed them to be, just as a defendant who was seeking to rely on a necessity defence would not be allowed to unless he could show that his actions were reasonable, all things considered.

However, the better analysis seems to be that in a self-defence case, the defendant is arguing that his conduct was justified not because he did more good than harm in using force against his attacker, but because his attacker had no right that the defendant not use force against him. For example, suppose that Anna is being raped by David when Anna manages to reach for a knife and stabs David to death. Most people agree that Anna is entitled to be acquitted of murder here: she will be able to take advantage of a defence of self-defence. But that is not because she did more good than harm in stabbing David to death. Whether or not that was the case is irrelevant. Anna’s conduct here was justified because David had no right that Anna not stab him to death, given what he was doing to Anna. By raping Anna, David forfeited the right he would have normally had against her that she not subject him to lethal force.

(Note that this analysis does not work to explain cases like R v Gladstone Williams (1984) where V was not actually attacking D, but D used force against V because she honestly believed V was a threat to her; in such a case, it is hard to say that V had no right that D not use force against him. Gladstone Williams must be explained on some other basis, such as that D’s conduct can be excused. But a problem with this is that in an excuse case, the defendant has to show that his conduct was reasonable, so as to allow the defendant to argue that ‘You would have done the same as me had you been in my position’ – and the effect of Gladstone Williams is to acquit a defendant who has acted on the unreasonable belief that he or she is being attacked.)

Statutory defences that look like necessity defences

There are some statutory defences that, it could be argued, look like forms of necessity defences:

(1) Damage to property

Under s 5(2) of the Criminal Damage Act 1971, a defendant who is charged with causing criminal damage to another’s property will have a defence if he acted as he did in order to protect other property from being damaged, and he acted reasonably in that belief. The classic example where this defence would apply where a fire is raging down a row of houses; the fire services will be authorised to pull down a house in the middle of the row so as to create a fire break and stop the fire spreading any further. By pulling down the house in the middle of the row, the fire fighters have done more good than harm and are entitled to justify their conduct on that basis.

(2) Refugees

Under s 31 of the Immigration and Asylum Act 1999, a defendant who has been charged with committing various offences in order to enter the UK will have a defence if he came to the UK directly from a country ‘where his life or freedom was threatened’ and promptly presented himself to the authorities and made a claim for asylum. A defendant who prevented himself being killed or imprisoned by entering the UK under a false passport, or by smuggling himself across the UK’s borders, will have done more good than harm and is entitled to justify his conduct on that basis.

(3) Crime stoppers

Section 3(1) of the Criminal Law Act 1967 says that ‘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.’ Provisions of the Police and Criminal Evidence Act 1984 confer numerous powers on the police to do things that would otherwise be criminal offences, such as stopping and searching someone (s 1), seizing property (s 19), arresting someone (s 24) and detaining someone in custody (Part IV). Such provisions can most easily be explained on the basis that the sort of conduct covered by these provisions is in the public interest and is therefore justified.

Necessity under the common law

It seems that the courts do not accept that a defendant who has been charged with a criminal offence can ever take advantage of a defence of necessity under the common law. So unless some statute provides the defendant with a necessity-type defence, it will not do the defendant any good to plead, ‘In acting as I did, I did more good than harm.’ Such a plea will fall on deaf ears.

This may seem a controversial claim, given the many cases in which the courts have begun to recognise the existence of a general defence of necessity and set out the situations in which such a defence will be available to a defendant. However, in all those cases (except two) the courts consistently run together the defence of necessity with the defence of duress of circumstances. They do this so consistently that when the courts talk of a defendant being allowed to take advantage of a defence of ‘necessity’ it seems that they are really talking about when a defendant will be allowed to take advantage of a defence of duress of circumstances.

Consider, for example, the following quote from Simon Brown J in R v Martin (1989) (driving while disqualified):

‘First, English law does, in extreme circumstances, recognise a defence of necessity. Most commonly this defence arises as duress, that is pressure upon the accused’s will from the wrongful threats or violence of another. Equally, however, it can arise from other objective dangers threatening the accused or others. Arising thus it is conveniently called “duress of circumstances”.

‘Secondly, the defence is available only if, from an objective standpoint, the accused can be said to be acting reasonably and proportionately in order to avoid a threat of death or serious injury.

‘Thirdly, assuming the defence to be open to the accused on his account of the facts, the issue should be left to the jury, who should be directed to determine these two questions: first, was the accused, or may he have been, impelled to act as he did because as a result of what he reasonably believed to be the situation he had good cause to fear that otherwise death or serious physical injury would result? Second, if so, may a sober person of reasonable firmness, sharing the characteristics of the accused, have responded to that situation by acting as the accused acted? If the answer to both those questions was yes, then the jury would acquit: the defence of necessity would have been established.’

This passage was endorsed in R v Abdul-Hussain (1998) (hijacking of plane) as providing ‘the clearest and most authoritative guide to the relevant principles’ as to when a defence of necessity would be available. (Which dictum was in turn approved in R v Shayler (2001) (breach of Official Secrets Act 1989) and R v S (2012) (child abduction).) But it is clear that Simon Brown J was not talking about necessity at all – in the sense in which I have defined that defence – but was rather talking about when a defendant will be able to take advantage of a defence of duress (either duress by threats or duress of circumstances). As we have already observed, duress is not necessity. As Brooke LJ observed in In Re A (2001) (separation of conjoined twins), ‘In cases of pure necessity the actor’s mind is not [as it is in duress cases] irresistibly overborne by external pressures. The claim is that his or her conduct was not harmful because on a choice of two evils the choice of avoiding the greater harm was justified.’

Despite this, the courts have continued to identify the defence of necessity with the defence of duress of circumstances. In R v Conway (1989) (reckless driving), Woolf LJ held that:

‘necessity can only be a defence to a charge of reckless driving where the facts establish “duress of circumstances,”… i.e. where the defendant was constrained by circumstances to drive as he did to avoid death or serious bodily harm to himself or some other person.  …Whether “duress of circumstances” is called “duress” or “necessity” does not matter. What is important is that, whatever it is called, it is subject to the same limitations as [the] “do this or else” species of duress.’

Twelve years on, in R v Shayler (2001, CA), Lord Woolf CJ was still of the same mind. Dismissing arguments that necessity and duress were distinct in that necessity is a justification and duress is an excuse, he said: ‘…the distinction between duress of circumstances and necessity has, correctly, been by and large ignored or blurred by the courts… the law has tended to treat duress of circumstances and necessity as one and the same’ (at [55]).

The two cases that might genuinely be said to have recognised the existence of a defence at necessity under the common law are Gillick v West Norfolk and Wisbech AHA (1986) and In Re A (2001). Let’s look at each of these in turn.

In Gillick, the issue was whether a doctor who prescribed contraception to a girl who under 16 would be guilty of an offence under s 28 of the Sexual Offences Act 1956 of causing or encouraging unlawful sexual intercourse ‘of a girl under the age of sixteen for whom he is responsible’. (Note that this offence was repealed by the Sexual Offences Act 2003, s 10 of which makes it an offence to cause or incite someone who is under 16 to engage in a sexual activity.) The majority (Lords Fraser, Scarman and Bridge) took the view that a doctor may well commit an offence under s 28 if he prescribed contraception to an under 16 year old girl ‘with the intention of facilitating her having unlawful sexual intercourse’, but a doctor could not be said to have such an intention if he was honestly prescribing the contraception ‘for the maintenance or restoration of [the girl’s] health.’ (Both quotes from Lord Scarman’s judgment.) The minority (Lords Templeman and Brandon) disagreed, holding that if a doctor prescribed contraception to a girl who was under 16, he would be ‘promoting, encouraging or facilitating the having of sexual intercourse’ (per Lord Brandon) and as a result would commit an offence under s 28. None of the judgments in Gillick say anything about necessity: they were purely concerned with the question of how s 28 of the 1956 Act should be interpreted. So there is nothing in Gillick that can be said to support the existence of a defence of necessity under the common law.

That leaves In Re A, in which the Court of Appeal had to decide whether it would be lawful to carry out an operation to separate two conjoined twins, Jodie and Mary, even though such an operation would inevitably result in the death of one of the twins, Mary. There was no possibility of arguing that the defence of duress of circumstances could apply to make the operation lawful: (1) duress cannot be excuse murder (a defendant cannot claim ‘you would have done the same as me’ when what he has done is intentionally kill someone else); (2) as Robert Walker LJ observed ‘The doctors are not faced with any threat to themselves, but they are faced with the anxious dilemma of trying to perform their professional duties which they owe to their two infant patients.’ So In Re A provided an excellent test case for whether the Court of Appeal were willing to recognise a defence of necessity independent of a defence of duress of circumstances.

All three judges in the Court of Appeal held that the doctors would not be committing a crime in operating to separate the conjoined twins.

Ward LJ held that the operation would be justified on the grounds of self-defence, as Mary – who was dependent on being supplied with blood from Jodie’s heart to stay alive, with the result that Jodie’s heart was destined to fail if she remained joined to Mary – posed an ‘unjust’ threat to Jodie’s life.

Brooke LJ held that the operation could be justified on the ground of necessity. He held that ‘there are three necessary requirements for the application of the doctrine of necessity: (i) the act is needed to avoid inevitable and irreparable evil; (ii) no more should be done than is reasonably necessary for the purpose to be achieved; (iii) the evil inflicted must not be disproportionate to the evil avoided.’ He thought that all three conditions were satisfied in this case. It is not, however, clear that Brooke LJ thought that satisfying conditions (i) – (iii) would be sufficient to give rise to a defence of necessity. A few paragraphs before setting out these conditions, he held that there were two objections to recognising a defence of necessity in a case where a defendant was charged with committing a criminal offence: (1) that it was beyond the competence of the courts to assess whether the operation would do more good than harm; (2) that allowing a defence of necessity would result in the court authorising someone to act immorally. Brooke LJ thought that neither objection applied In Re A. On (1), it was obvious whether or not the operation would do more good than harm: dealing with this question did not require the courts to put a comparative value on Jodie and Mary’s lives. If the operation were not carried out, both Jodie and Mary would die. If it were carried out, Jodie would live and Mary would die. Given this, it was obvious what was the better option. On (2), it was not clear that carrying out the operation would be an immoral act, so it was not clear that by allowing the operation to be carried out the court would be ‘marking an absolute divorce of law from morality’.

Robert Walker LJ seemed to take the view that the operation did not even approach the threshold of criminality that would require the doctors to rely on a defence to justify or excuse their actions. He held that the doctors carrying out the operation could not be said to have intended to kill Mary (so they would not have the mens rea for murder), and could be said to be acting in Mary’s best interests in carrying out the operation as ‘The operation would give her, even in death, bodily integrity as a human being’ (so they would not be breaching the duty of care they owed Mary as her doctors in carrying out the operation and could not therefore be held guilty of gross negligence manslaughter).

So – of the three judges who decided In Re A, only one (Brooke LJ) rested his decision on the basis that the doctors could take advantage of a defence of necessity which was genuinely distinct from a defence of duress of circumstances. And Brooke LJ’s judgment remains the only English authority that there exists a defence of necessity at common law that is distinct from a defence of duress of circumstances. Given this, it seems fair enough to say that the English law does not currently recognise that a defendant who has been charged with a criminal offence can ever rely on a defence of necessity to justify his conduct in the absence of some specific statutory provision which allows him to raise a necessity-type defence to the charge.

Why are the courts so unwilling to recognise a free-standing defence of necessity?

There seem to be four reasons for the lack of authority in favour of the proposition that a defendant is entitled to be acquitted of a criminal charge if he can show that he did more good than harm in acting as he did.

(1) The definition of offences

There are two ways in which the definition of an offence can exclude a defendant from seeking to rely on a defence of necessity to justify his conduct.

First, the definition of an offence may make it unnecessary for the defendant to rely on a defence of necessity to justify his conduct, because the facts which the defendant might have wanted to rely on as giving him a defence of necessity will also allow him to argue that he does not commit the actus reus of the offence with which he is charged, or that he did not commit the actus reus of the offence with the requisite mens rea. For example, in R v Abdul-Hussain (1998), Rose LJ observed that ‘if Anne Frank had stolen a car to escape from Amsterdam and been charged with theft, the tenets of English law would not have denied her a defence of duress of circumstances, on the ground that she should have waited for the Gestapo’s knock on the door [before attempting to escape in a stolen car].’ But in such a case Anne Frank would not have needed to rely on a defence to avoid being convicted of theft. She would have been able to argue that in the circumstances, her appropriation of the car was not dishonest – with the result that she did not commit the actus reus or mens rea of theft (depending on how you classify the requirement of dishonesty in theft, as going to the actus reus or the mens rea of theft).

Secondly, where an offence has been created under a statute, it might be impossible for the defendant to rely on a defence of necessity to justify his conduct because it will be clear from the definition of the offence that Parliament did not intend such a defendant to be allowed to escape conviction by pleading that his actions were in the public interest. The most obvious example of this is the Official Secrets Act 1989. The Act does not provide any defence to someone who claims that they were acting in the public interest in making public secrets ‘relating to security or intelligence’ that they came across by virtue of their position as ‘a member of the security and intelligence services’ or as a government official who has been notified that they are bound by the Act. Given this, the courts would be flouting the will of Parliament if they were to allow such a defendant a defence of necessity under the common law; and they so ruled in the case of R v Shayler (2003, HL). For similar reasons, the appeal in R v Quayle (2005) – where the defendant attempted to justify their possession of marijuana on the basis of ‘medical necessity’ – was doomed to fail. The Misuse of Drugs Act 1971 provides no defence to those who possess marijuana for medical purposes. Given the extreme likelihood that this was a deliberate decision on the part of Parliament, it would have been a violation of Parliamentary sovereignty for the courts to hold that the defendants in Quayle were entitled to a defence of necessity. It was different in DPP v Pipe (2012), where the defendant was charged with breaking the speed limit when he drove his son – who had broken his leg playing football – to hospital. Allowing him to rely on a defence of necessity (here, a synonym for ‘duress of circumstances’) did not involve the courts in violating the will of Parliament in setting speed limits for motorists. Parliament – or the ministers exercising powers to set speed limits delegated to them by Parliament – could not be expected to have had circumstances such as those in DPP v Pipe in mind in setting speed limits.

(2) Rights

Most common law offences exist to protect individual’s rights that other people not treat them in certain ways (kill them, rape them, take their property, batter them, and so on). The fact that English law recognises that people have rights reflects the individualistic ethos of English law, under which greater priority is placed on protecting the freedom of the individual than the welfare of the community. Rights give people a veto power over what can be done to them in the name of the public interest. In Ronald Dworkin’s vivid phrase, ‘rights are trumps’.

In contrast, the existence of necessity defences reflect a more communitarian ethos, under which greater priority is placed on promoting the welfare or the community than on protecting the freedom of the individual. If ‘I did more good than harm’ were always a defence to being charged with committing a criminal offence, then people would have no rights. All people would have were interests that would be taken into account in determining what the right thing to do would be. So if V’s interests in not being killed by D were outweighed by the community’s interests in seeing that V was killed by D, then the law would permit V to be killed by D. It would not be possible anymore to say that V had a right not to be killed by D because killing V might be allowed, depending on the circumstances.

Of course, if the balance of interests indicated that V should not be killed, then we could say in that situation that V has a right not to be killed by D. But that statement, that V has a right not to be killed by D, would simply represent the conclusion of a chain of reasoning: ‘It would do more harm than good to kill V, so V should not be killed, so V has a right not to be killed by D.’ The statement that V has a right not to be killed by D would not – as it does in a community which adopts an individualistic ethos – form the premise of a chain of reasoning: ‘V has a right not to be killed by D, so it would be wrong for D to kill V even though killing V would, on balance, do more good than harm.’

It follows that so long as English law adopts an individualistic ethos, it cannot recognise the existence of necessity defences to crimes which involve violating an individual’s rights. Recognising the existence of such defences would be fatal to English law’s individualistic ethos, in the same way that kryptonite is fatal to Supeman: they cannot co-exist in the same space. English law could not at one and the same time recognise that people have rights and recognise that a defendant could justify treating someone in a particular way by arguing ‘I did more good than harm.’ It has to be one or the other; not both. Once we grasp this, we can see that arguments about whether the law should recognise a defence of necessity (in the sense that it has been defined in this essay, a justification based on the plea ‘I did more good than harm’) are really debates about whether the law should be influenced by an individualistic ethos or by a communitarian ethos. And the fashionability of communitarian ideas among academics explains why so many academics are in favour of the criminal law recognising a fully-fledged defence of necessity.

(3) Judgment

Even if English law were to adopt a more communitarian ethos – and many people would say that it has been in the process of doing that since the 1970s – the courts would still have good reason to hesitate over whether or not to allow defendants to rely on a necessity defence, at least in cases where they are not excluded from doing so by the terms of the offence with which they have been charged. In a case where a defendant argued ‘My conduct was justified because I did more good than harm’, it will often be very difficult for the courts to judge whether or not the defendant’s argument is made out. The problem is not really that the courts lack the expertise to weigh the goods and harms that were produced by the defendant’s conduct, but more that no one could weigh those goods and harms because no one can tell what those goods and harms are. For example, in R v Dudley and Stephens (1884), the court held that the defendant seaman – who had abandoned ship in the middle of a storm and put to sea in an open boat with a cabin boy – could not justify killing the cabin boy in order to eat his body on the basis that had they not done so, they would have all starved to death. Lord Coleridge CJ pointed out that even if it were the case (which was not actually certain, as they might have been picked up any day by a passing ship; or they might not have been picked up at all, ever) that the people in the open boat had a choice between ‘One of us dies, and the rest of us live’ and ‘We all die’, that could not justify killing the cabin boy as opposed to any of the other people in the boat. Killing the cabin boy could only be justified if that was the least worst option. But:

‘Who is to be the judge of this sort of necessity? By what measure is the comparative value of lives to be measured ? Is it to be strength, or intellect, or what? …In this case the weakest, the youngest, the most unresisting, was chosen. Was it more necessary to kill him than one of the grown men? The answer must be “No”…’

None of us can really tell what the consequences of our actions will be. Given this, asking the courts to determine whether the defendant’s actions did more good than harm is asking them to do the impossible. Even in a case like In Re A, where it seems clear-cut that going ahead with the operation would do more good than harm, it is not impossible to imagine futures where not carrying out the operation would have been the better option: for example, a future where Jodie grew up to become a mass murderer, or a future where Jodie became so depressed at owing her life to the death of her twin that she was never able to function normally or enjoy life. And it is not impossible to imagine twists on those futures that would allow us to say that, in fact, carrying out the operation was actually still the better option, where the tragedies resulting from Jodie’s existence had outcomes that worked to offset the initial suffering involved in those tragedies.

(4) Disorder

The final reason for being cautious about recognising the existence of necessity defences, even in a legal system that is fully committed to adopting a communitarian ethos, is the potential for disorder that the existence of such defences creates. The criminal law will speak with a more uncertain voice, and provide less of a constraint on people’s actions, if people know that their conduct will not be attract a criminal sanction if they can establish that they did more good than harm in acting as they did. This consideration played some part in the decision of the court in R v Dudley and Stephens to deny a necessity defence to the defendants in that case. Lord Coleridge CJ warned of the ‘awful danger’ involved in allowing that ‘the temptation to murder’ could give rise to a defence to a charge of murder:

‘such a principle once admitted might be made the legal cloak for unbridled passion and atrocious crime. There is no safe path for judges to tread but to ascertain the law to the best of their ability and to declare it according to their judgment… [A judge] has no right to declare temptation to be an excuse, though he might himself have yielded to it, nor allow compassion for the criminal to change or weaken in any manner the legal definition of the crime.’

Almost a hundred years later, in Southwark London Borough Council v Williams (1971), Lord Denning MR advanced similar reasons for refusing to find that squatting in abandoned premises could be justified on the grounds of necessity:

‘The doctrine [that private property may be sacrificed to avoid ‘great and imminent danger’] must…be carefully circumscribed. Else necessity would open the door to many an excuse. It was for this reason that it was not admitted in Reg. v. Dudley and Stephens (1884) 14 Q.B.D. 273, where the three shipwrecked sailors, in extreme despair, killed the cabin boy and ate him to save their own lives. They were held guilty of murder. The killing was not justified by necessity. Similarly, when a man, who is starving, enters a house and takes food in order to keep himself alive. Our English law does not admit the defence of necessity. It holds him guilty of larceny. Lord Hale said that “if a person, being under necessity for want of victuals, or clothes, shall upon that account clandestinely, and animo furandi, steal another man’s food, it is felony…”: Hale, Pleas of Crown, i. 54. The reason is because, if hunger were once allowed to be an excuse for stealing, it would open a way through which all kinds of disorder and lawlessness would pass. So here. If homelessness were once admitted as a defence to trespass, no one’s house could be safe. Necessity would open a door which no man could shut. It would not only be those in extreme need who would enter. There would be others who would imagine that they were in need, or would invent a need, so as to gain entry. Each man would say his need was greater than the next man’s. The plea would be an excuse for all sorts of wrongdoing. So the courts must, for the sake of law and order, take a firm stand. They must refuse to admit the plea of necessity to the hungry and the homeless: and trust that their distress will be relieved by the charitable and the good.’

Conclusion

It seems that the current state of law on when a defence of necessity (properly understood as a justification resting on the argument ‘I did more good than harm’) will be available is justified. If necessity-type defences are to be recognised under the law, it would be better if they were created by Parliament, rather than the courts. Giving effect to statutory necessity defences would pose no threat to the doctrine of Parliamentary sovereignty. Moreover, Parliament is in a better position than the courts to judge when acting in a particular way can be justified on the basis that acting in that way did more good than harm, and to set out what factors are to be taken into account in reaching that conclusion. Further, the statutory necessity-type defences are less likely to be abused or misused as their scope should be clearly delineated and understood in advance; something that is not possible when the courts undertake to sketch out on a case-by-case basis when they will permit a defendant to rely on a necessity defence.