Criminal Law Defences

  • Created by: Holly
  • Created on: 07-06-14 11:57


  • M'Naughten Rules - Labouring under a defect of reason, from a disease of the mind so they do not know the nature/quality of their act or do not know what they did was wrong.
  • Defect of Reason - The ability to reason is impaired. If the defendant is capable of reasoning but has failed to use it, this is not a 'defect of reason'. The case of Clark held that it must be more than absent-mindedness/confusion.
  • Disease of the mind - A mental or physical disease that affects the mind. The case of Kemp demonstrates how arteriosclerosis satisfied 'disease of the mind'. In the case of Sullivan, epilepsy satisfied diease of the mind, they also held it did not matter if it was permanent, transient or intermittent. In Hennesy, diabetes satisfied it, and in Burgess a sleep disorder also satisfied it.
  • Not knowing the nature/quality of the act - Can be due to unconsciousness/impaired consciousness or when conscious but the mental condition means they do not know what they are doing.
  • Not knowing what they did was wrong - Legally and not morally. The case of Windle demonstrates this where he did not satisfy this because he said 'I suppose they will hang me for this', and was 'reluctantly' followed in the case of Johnson. An Australian case thought that if the d thought it was right according to the standards of the reasonable man then he could be acquitted, even if they knew it was legally wrong.
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Insanity 2

  • Special verdict - Not guilty by reason of insanity. Pre 1991 the sentance was always indefinite mental hospital order. Criminal Procedure Act 1991 - Judges can now impose hospital orders, supervision orders or absolute discharge except in murder cases.
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Comment on Insanity

  • M'Naughten rules are from 1843. Very old, outdated. From an era where there was little knowledge of mental disorders. 
  • Definition is a legal one rather than a psychiatric one. This means people suffering from certain mental disorders do not come within the definition such as psychopaths and also that some people suffering from physical diseases do such as diabetes.
  • Overlaps with Automatism. The defence of Automatism is not available from epileptics and diabetics, this can have serious consequences as the max sentances are different.
  • A person who is suffering from a serious recognised illness and does not know his act is morally wrong cannot have a defence of insanity where he knows his act is legally wrong.
  • 'Insanity' carries social stigma, it may be inappropriate to apply it to epilepsy or diabetes.
  • Burden of proof is on the defendant to prove they are insane, this breaches human rights Art 6 - innocent until proven guilty.
  • Jury is used to decide if insane or not. Surely this should be done by medical professionals? Juries have to listen to complicated evidence and so there may be confusion over terminology. Even if agreed they are insane, may still return verdict of guilty anyway as seen in Peter Sutcliffe's case.
  • Overlaps with Diminished Responsibility which covers a wider range of medical illnesses and has more sentancing options.
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Insanity - Reform

  • M'Naughten rules should be extended so that a defendant should be considered insane if they were incapable of preventing themselves from committing the offences.
  • However, the government reformed Diminished Responsibility in the Coroners and Justice Act 2009 and have not reformed insanity.
  • 'Not guilty by reason of insanity' vs 'Not guilty on evidence of medical disorder'
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  • "An act done by the muscles without any control by the mind, such as spasm, a reflex action or  convulsion, or an act done by a person who is not conscious of what he is doing such as an act done whilst suffering from concussion or whilst sleepwalking"
  • Insane Automatism = Insanity. Non-insane Automatism = Causes of act external, where the defence succeeds they are acquitted.
  • Automatism is a defence because the actus reus was not voluntary and do not have required mens rea. This was approved in Hill v Baxter.
  • Case of T held that exceptional stress can be an external factor
  • AGs ref (2 of 1992)1993 held that there must be a 'total destruction of voluntary control'
  • Examples of external causes include 
  • A swarm of bees attacking
  • A blow to the head
  • Sneezing
  • Hypnotism
  • Effect of a drug.
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Self-induced Automatism

  • Defendant knows their conduct is likely to bring on an automatic state.
  • Bailey - Defendant did not eat after taking insulin and so it was self-induced and the defence was not available.
  • The law assumes that when self-induced automatism occurs, the defendant has been reckless.
  • If the defendant commits a specific intent offence, they can use the defence of automatism because they my have not satisfied 'intention'
  • Usually for basic intent offences, the defence cannot be used because they have developed the necessary level of mens rea. This comes from the case of Bailey.
  • The case of DPP v Majewski held that being voluntarily intoxicated with drink/drugs was reckless conduct. Self - induced Automatism is not available for basic intent offences where the defendant was voluntarily intoxicated.
  • Where the defendant does not know that their actions are likely to lead to an automatic state, they have not been reckless and so automatism may be allowed to be used for basic intent offences in these cases. Demonstrated in the case of Hardie.
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Comment & Reform of Automatism

  • Difficult to decide if insane or non-insane automatism, and a significant decision to make.
  • Draft Criminal Code suggested that a person should not be guilty of an offence if
  • 1) He acts in a state of automatism
  • 2) So, that act is a reflex, spasm or convulsion or
  • 3) Occurs while they are in a condition depriving him of effective control of his act and
  • 4) The act or condition is the result of neither anything done/ommitted with the fault required for the offence, nor of voluntary intoxication.
  • This means that a person will not be guilty if they are in a state of automatism that is an act, or in a state of automatism that occurs while they are in a condition they cannot control, and this is not due to voluntary intoxication and they have not formed the mens rea.
  • This would include epilepsy and sleepwalking, however, this may leave an unintentionally dangerous person to commit the same offence again.
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  • Covers intoxication by alchohol, drugs or other substances and is relevant as to whether the defendant has the required mens rea for the offence. If they do not have the required mens rea they may not be guilty. This depends on whether the intoxication was voluntay or involuntary and whether it is one of basic/specific intent.
  • Voluntary intoxication. - Can provide a defence for a specific intent offence, if the d was so intoxicated they could not have formed the mens rea, decided in DPP v Beard. In Sheehan and Moore it was found that they were too drunk to have formed the mens rea of murder. Where the defendant still forms the mens rea depite being intoxicated, there is no defence. This was seen in the case of Gallagher. Where the offence is one of basic intent there is not defence due to the DPP v Majewski principle.
  • Involuntary intoxication - Not a defence where the mens rea is still formed by the defendant - Kingston. However, in most cases involuntary intoxication will provide a defence for both specific and basic intent offences as the d has not been reckless.
  • Intoxicated Mistake - If the d is mistaken about a key fact due to intoxication there may be a defence, it depends what the key fact is. If they are mistaken by something which means they could not have formed intention, there is a defence for specific intent offences, but not basic intent offences as seen in Lipman. Intoxicated mistake as to the use of 'reasonable force' in self defence will never provide a defence under the Criminal Justice and Immigration Act
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Comment on Intoxication

  • Public policy based because it is a major factor in many violent crimes and there is a need to protect the victim's rights.
  • Public policy aims to encourage good behaviour. Legal principles impose liability where there is fault, which must be voluntraily assumed, so there may be contradictions.
  • Some areas seem contrarty to the normal rules that actus reus and mens rea must coincide
  • Recklessness in becoming intoxicated means the defendant is seen to be taking a general risk of doing something 'stupid' or committing a crime, they may have no idea that they will commit an offence.
  • The Law Commission though that the law opertated 'fairly on the whole'
  • A defendant can be found guilty of a basic intent offence instead of a specific intent offence where one exists, for example, murder can be downgraded to manslaughter. However, where there is no accompanying basic intent offence, the defendant may simply be acquitted. There seems no logical pattern where basic intent crimes accompany specific intent crimes.
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Reform of Intoxication

  • Butler committe proposed 'Dangerous intoxication' offence to be used when a defendant was acquitted of a dangerous offence due to intoxication. 1 year max imprisionment for the first offence, and 3 years for any subsequent offences. It was rejected because it did not distinguish how serious the orginal offence was.
  • Law Commission proposed the offence of 'criminal intoxication'
  • In 2009 they proposed to abolish the terms 'specific' and 'basic' intent and simply changed to offences where mens rea is an integral fault element, and offences where is it not. They also proposed that where the d was voluntarily intoxicated and charged with a basic intent crime, the d should be treated as if sober.
  • It was argued that there should be a list of situations which count as involuntary intoxication including spiked drinks, forced intoxication and reasonably believing the substance was not intoxicating.
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  • Defendant has been forced to commit a crime as they were threatened with death or serious injury, It is not available for murder, attempted murder, or treason.
  • In the case of Howe, the HoL said that duress was never a defence for murder or attempted murder. The case of Wilson held that age/impressionality of the defendant were irrelevant and the case of Gotts confirmed duress could not be used for attempted murder.
  • Two types - Duress of Threats and Duress of Circumstances.
  • Duress of Circumstances - Recognised by the case of Willer, and confirmed in the cases of Conway and Martin. The case of Pommell confirmed that duress of circumstances was availbale to all crimes except murder, attempted murder and treason.
  • Intoxication and duress - If the d mistakenly believes they are being threatened due to intoxication duress is not available. However, if intoxication is irrelevant then it does not prevent the use of the defence.
  • Self-induced Duress - Where the defendant is aware that they may be put under duress, the defence is not available. This includes joining a violent gang and was seen in the cases of Sharp and Heath. The case of Hasan held that duress is not available where the defendant ought to have realised they may be threatened with violence and compelled to commit an offence. Shepard held that where the defendant has no knowledge they may be subjected to duress the defence is available.
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Duress of Threats

  • A person's will is overbourne by threats of death or serious injury. Lesser threats do not provide a defence. Valerrama-Vega held that the cumulative effect of the threats can be considered, although they must still be of serious injury or death.
  • The threat can be directed at other people than the defendant, such as family and friends. This was seen in Martin and Conway. There have been no decisions as to strangers, but it seems likely that a threat towards a stranger would still satisfy duress.
  • Jury must consider the Graham test. 1) Was the defendant compelled to act as he did because he reasonably believed he had good reason to fear serious injury or death? 2) If so, would a sober person of reasonable firmness, sharing the characteristics of the accused, have responded in the same way? Confirmed in Howe.
  • Martin held that genuine mistaken belief will still allow for a defence, so d's mental condition is relevant in whether they reasonably belived in the threat. However, Hasan held that the belief in the threats must be real and genuine
  • The Jury can take into account the characteristics of the d, the case of Bowen said that age, pregnancy, serious physical disability, recognised mental illness and gender could be considered.
  • Duress can only be used if the defendant is placed in the situation where there is no avenue of escape as in the case of Gill. The status of police protection is unclear due to the cases of Hudson and Taylor and Hasan
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Duress of Threats 2

  • The threat must be 'effective' at the moment the crime was committed, but do not need to be carried out immediately as in Hudson and Taylor.
  • Abdul-Hussain held that there must be imminent peril of death/serious injury to the defendant or those for whom he has responsibility, and must operate on the defendants mind at the time of committing the act, it need not be immediate.
  • The case of Cole demonstrated that there must be a threat to commit a specific offence.
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Comment on Duress

  • Not available to hijacked getaway drivers in murder cases?
  • Rules on murder are harsh and require 'heroism'. Age + susceptbility are ignored
  • Not available for murder but is available for GBH but same level of mens rea?
  • Duress cannot affect the sentancing in a murder case due to mandatory life sentance, but can be considered for attempted murder. It has been suggested that duress should be a defence for murder.
  • Low IQ cannot be taken into account under Bowen, even if the nature of matters is not understood - unfair?
  • Uncertain as to police protection.
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  • Where circumstances force a person to act in order to prevent a worse evil from occuring.
  • In Dudley and Stephans it was held necessity was not a defence to murder, and Denning thought that necessity could be available for eergancy services violating traffic laws, although they have since been ammended to allow for this.
  • Re:F allowed the defence of necessity where an adult had disabled consent, for doctors to perform medical procedures.
  • Re:A - Necessity a defence to murder? Agreed with the guidelines in the Criminal Draft Code
  • 1) The act was done to avoid consequences which could not otherwise be avoided 2) The consequences would have inflicted inevitable and irreprable evil 3) No more was done than was reasonably necessary 4) The evil inflicted was not disproportionate to the evil avoided.
  • The case of Shayler held that duress of circumstances and necessity were in effect the same defence.
  • The test is 1) The act must be done only to prevent an act of greater evil 2) That evil must be directed towards the defendant/persons for whom the defendant is responsible and 3) Must be reasonable and proportionate to the evil avoided.
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