Which general defences can reduce or remove criminal liability, and what must each one prove?
The general defences: insanity and automatism, intoxication (voluntary and involuntary), self-defence and the prevention of crime, consent, and duress by threats and of circumstances.
An Eduqas A-Level Law guide to the general defences. Explains insanity, automatism, intoxication, self-defence, consent and duress, and how they reduce or remove liability, with worked scenario answers and the AO2 application the paper rewards.
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What this dot point is asking
Eduqas criminal law requires you to know the general defences that can reduce or remove liability: insanity and automatism, intoxication (voluntary and involuntary), self-defence and the prevention of crime, consent, and duress (by threats and of circumstances). The skill is to apply the right defence to a scenario (AO2) and to evaluate a defence such as insanity (AO3).
The answer
Insanity and automatism
Intoxication
Intoxication affects the mens rea. Voluntary intoxication (drink or drugs taken knowingly) is a defence only to crimes of specific intent (murder, s18, theft) where it prevented the defendant forming the mens rea (DPP v Majewski); it then reduces the offence to any available basic-intent alternative (murder to manslaughter, s18 to s20). It is no defence to basic-intent crimes (assault, battery, s47, s20), because getting drunk is itself reckless. Involuntary intoxication (a spiked drink, or prescribed medication) is a defence if it prevented the mens rea, but not if the defendant still formed the mens rea (a drunken intent is still an intent, Kingston).
Self-defence and consent
Duress
Duress by threats is a complete defence where a crime is committed under a threat of death or serious injury. The Graham/Howe two-limb test asks: (1) did the defendant reasonably believe they faced death or serious injury; and (2) would a sober person of reasonable firmness, sharing the defendant's characteristics, have acted the same way? Duress of circumstances applies the same test where the pressure comes from the situation (R v Martin). Duress is never a defence to murder, attempted murder or treason (Howe; Gotts), needs a threat that is effectively immediate with no safe escape (R v Hasan), and is unavailable where the defendant voluntarily joined violent criminals foreseeing coercion (Hasan).
Examples in context
A strong answer states the precise test and applies its limits, not just the general idea of the defence.
Try this
Q1. Explain the defence of voluntary intoxication. [10 marks]
- What the marker wants. Precise AO1: voluntary intoxication is a defence only to specific-intent crimes where it prevents the mens rea (DPP v Majewski), reducing the offence to a basic-intent alternative; it is no defence to basic-intent crimes because becoming intoxicated is itself reckless.
Q2. Aaron, mistakenly but genuinely believing he is about to be attacked, punches a stranger and breaks his nose. Advise on whether Aaron can rely on self-defence. [20 marks]
- Cue. An AO2 application: necessity is judged on the facts as Aaron honestly believed them, even if mistaken (Gladstone Williams), so an honest mistake does not defeat the defence (unless from voluntary intoxication, O'Grady); the force must be proportionate (s76), so the issue is whether a single punch was a reasonable response to the perceived threat.
Exam-style practice questions
Practice questions written in the style of WJEC Eduqas exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
Eduqas Component 2 2022 (scenario)20 marksTwo masked men threaten to kill Reece's family unless he drives them to a bank and helps them rob it. Reece does so. Advise on whether Reece can rely on the defence of duress. [a scenario in the style of Component 2; the real paper tariff is 25, AO1 and AO2]Show worked answer →
A mainly AO2 scenario on duress by threats.
The Graham/Howe test. (1) Was Reece compelled to act because he reasonably believed he would face death or serious injury (the threat to his family qualifies)? (2) Would a sober person of reasonable firmness sharing Reece's characteristics have responded the same way? Apply both limbs.
Limits. Duress is no defence to murder or attempted murder (Howe; Gotts), but robbery is not excluded. The threat must be effectively immediate with no safe avenue of escape (Hasan/Z); Reece had no obvious chance to go to the police. Duress is unavailable if the defendant voluntarily joined a violent criminal gang foreseeing coercion (Hasan); there is no suggestion Reece did.
Conclusion. If both limbs of the Graham test are met and no exclusion applies, duress provides a complete defence to the robbery.
A top answer applies the two-limb test and the limits (excluded offences, immediacy, self-induced duress) to the facts.
Eduqas Component 3 2021 (essay)20 marksAnalyse and evaluate the defence of insanity. [an essay in the style of Component 3; the real paper tariff is 25, AO1 and AO3]Show worked answer →
A mainly AO3 essay. Explain the M'Naghten rules, then evaluate them.
The law. The M'Naghten rules require a defect of reason, from a disease of the mind, so that the defendant did not know the nature and quality of the act, or did not know it was wrong. 'Disease of the mind' is a legal, not medical, concept (Kemp; Sullivan; Hennessy on diabetes; Burgess on sleepwalking), which produces odd results.
Evaluation. Weaknesses: the rules date from 1843 and use outdated language; 'disease of the mind' wrongly includes physical conditions like epilepsy and diabetes (Hennessy) but may exclude some genuine mental illness; the label 'insane' is stigmatising; the burden is on the defendant; and the special verdict (not guilty by reason of insanity) carries stigma though disposal is now flexible. The Law Commission has proposed reform.
A top answer explains the M'Naghten rules with cases and evaluates their age, scope and fairness, then concludes.
Related dot points
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An Eduqas A-Level Law guide to the general elements of criminal liability. Explains actus reus, omissions and causation, mens rea (intention and recklessness), coincidence, transferred malice and strict liability, with worked scenario answers and the AO2 application the paper rewards.
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- The non-fatal offences against the person: assault and battery (common law), assault occasioning actual bodily harm (s47), malicious wounding or inflicting grievous bodily harm (s20), and wounding or causing grievous bodily harm with intent (s18) under the Offences Against the Person Act 1861.
An Eduqas A-Level Law guide to the non-fatal offences against the person. Explains assault, battery, s47, s20 and s18 of the Offences Against the Person Act 1861, their actus reus and mens rea and the leading cases, with worked scenario answers and the AO2 application the paper rewards.
- Property offences: theft under the Theft Act 1968 (appropriation, property, belonging to another, dishonesty and intention permanently to deprive) and robbery under section 8 (theft with the use or threat of force in order to steal).
An Eduqas A-Level Law guide to the property offences of theft and robbery. Explains the five elements of theft under the Theft Act 1968 and the added force element of robbery, with worked scenario answers and the AO2 application the paper rewards.
- The evaluation essay (AO3): structuring a balanced argument, analysing strengths and weaknesses, using examples, cases and reform proposals, and reaching a reasoned conclusion.
An Eduqas A-Level Law guide to the evaluation essay (AO3). Explains how to structure a balanced argument, analyse strengths and weaknesses, use examples and reform proposals and reach a conclusion, with worked examples and the technique the Component 3 paper rewards.
Sources & how we know this
- Eduqas A Level Law (A150) specification — WJEC Eduqas (2017)