General defences - Intoxication

Learning Outcomes

This article explores the legal principles surrounding intoxication in criminal law, including:

• Effects of intoxication on the formation of mens rea and its potential to negate criminal liability
• The distinction between voluntary and involuntary intoxication
• Interactions of intoxication with specific intent and basic intent offences
• Dangerous versus non‑dangerous intoxicants and the impact of classification on analysis
• The Majewski rule for basic intent crimes and the contrasting approach for specific intent crimes
• Involuntary intoxication across both basic and specific intent offences, contingent on actual formation of mens rea
• The principle that drunken or drugged intent is still intent
• Intoxication and other defences, including self‑defence, statutory lawful excuse for criminal damage, and mistaken belief requirements in sexual offences
• The limited or non‑existent role of intoxication in strict liability offences
• Evidential burdens on the defendant and legal burdens on the prosecution when intoxication is raised, including standard jury directions on drunken intent
• Relevance to SQE1 assessments and criminal culpability analysis

SQE1 Syllabus

For SQE1, you are required to understand the rules relating to intoxication and its effect on establishing criminal liability. Intoxication is not a defence in itself but may be relevant where it prevents the defendant from forming the necessary mens rea for an offence, with a focus on the following syllabus points:

• The distinction between voluntary and involuntary intoxication.
• The difference between crimes of specific intent and basic intent.
• How voluntary intoxication may operate in relation to specific intent crimes but not basic intent crimes.
• How involuntary intoxication may operate in relation to both specific and basic intent crimes.
• The impact of intoxication on other defences, such as mistake in self-defence.
• The classification of intoxicants into dangerous (e.g., alcohol/illegal drugs) and non‑dangerous (e.g., soporific prescription medication) and its relevance (Hardie).
• The treatment of sexual offences as basic intent offences and the requirement of a reasonable belief in consent that is not based on intoxication.
• The evidential burden on the defendant to raise intoxication and the prosecution’s legal burden to prove intent despite intoxication (including standard jury directions on drunken intent).
• Statutory codification of self‑defence principles and the exclusion of intoxicated mistakes (CJIA 2008, s 76(5)).
• The Dutch courage rule and why intent formed before intoxication remains operative.
• The non‑availability of intoxication for strict liability offences.

Test Your Knowledge

Attempt these questions before reading this article. If you find some difficult or cannot remember the answers, remember to look more closely at that area during your revision.

1. Can voluntary intoxication provide a defence to a charge of murder?
   1. Yes, always.
   2. No, never.
   3. Yes, if the defendant was so intoxicated they could not form the specific intent required.
   4. Yes, but only if the defendant was also suffering from a mental illness.
2. Which of the following offences is generally considered a crime of basic intent?
   1. Murder
   2. Theft
   3. Assault occasioning actual bodily harm (ABH)
   4. Wounding with intent (s.18 OAPA 1861)
3. If a defendant's drink is spiked without their knowledge (involuntary intoxication), and they commit an assault (a basic intent crime), can they potentially rely on their intoxication?
   1. No, intoxication is never a defence to basic intent crimes.
   2. Yes, but only if they can also show they acted in self-defence.
   3. Yes, if the involuntary intoxication meant they lacked the necessary mens rea (intent or recklessness) for assault.
   4. No, unless the substance taken was a prescribed medication.

Introduction

Intoxication relates to the state of being under the influence of alcohol, drugs, or another substance affecting mental judgment or physical control. In criminal law, intoxication is not a defence in itself. Instead, its relevance lies in whether the defendant possessed the required mens rea (guilty mind) for the offence charged at the time the actus reus (guilty act) was committed. If intoxication prevents the defendant from forming the necessary mens rea, they may not be liable for the offence. The legal rules differ significantly depending on whether the intoxication was voluntary or involuntary, and the type of crime involved (specific or basic intent).

Two core themes run through all intoxication analysis:

• the “specific intent/basic intent” divide (per DPP v Majewski), and
• the “dangerous/non‑dangerous” substance distinction.

Alcohol and illegal drugs are treated as dangerous intoxicants. Their voluntary consumption will not assist a defendant on a basic intent offence, and will only be relevant to negate specific intent if the defendant truly lacked the capacity to form intention at the time. By contrast, unexpected effects from non‑dangerous soporific medication taken as prescribed may, in some circumstances, be treated similarly to involuntary intoxication. Across all contexts, if the evidence shows that the defendant nevertheless formed the relevant intention or foresaw the risk and proceeded unreasonably, intoxication does not absolve liability. In short: drunken or drugged intent is still intent.

Intoxication has limited or no operation against strict liability offences because they do not require proof of a mental element. It can, however, interact with other defences. For example, a mistaken belief induced by voluntary intoxication cannot ground self‑defence (statutory exclusion under CJIA 2008, s 76(5)), whereas certain statutory honest‑belief defences (such as lawful excuse under the Criminal Damage Act 1971) can succeed even if the belief was formed while intoxicated.

Involuntary Intoxication

This occurs where a defendant becomes intoxicated through no fault of their own. This typically arises in two main situations: where the defendant's food or drink has been 'spiked' without their knowledge, or where they have an unexpected or unforeseeable reaction to prescribed medication taken in accordance with medical advice. Soporific drugs (drugs which induce drowsiness or sleep) taken voluntarily, where the effect is merely drowsiness, may also fall under this category if the defendant was not reckless in taking them.

Key Term: Involuntary Intoxication
Intoxication caused by the administration of a substance without the defendant's knowledge or consent, or due to an unforeseen reaction to medication taken as prescribed.

Involuntary intoxication can potentially negate the mens rea for both specific and basic intent crimes. If the defendant, due to involuntary intoxication, did not form the necessary intention or recklessness required for the offence, they may be acquitted. However, the intoxication must have prevented the formation of the mens rea. If the defendant, despite being involuntarily intoxicated, still formed the necessary mens rea, they will remain liable (as established in R v Kingston). Drunken or drugged intent is still intent.

The courts emphasise that “involuntary” does not extend to mistakes about strength or quantity. A person who knowingly consumes alcohol but underestimates its strength is voluntarily intoxicated (R v Allen). Ignorance of potency does not convert voluntary intoxication into involuntary.

In mixed scenarios (part voluntary, part involuntary), the tribunal of fact will assess how each component contributed to the defendant’s state, and whether the defendant lacked mens rea. For example, where a defendant takes a single prescribed sedative (non‑dangerous) as directed but has their soft drink spiked with alcohol, the court will consider the combined effect and whether the defendant’s mental state was non‑culpably impaired such that intention or subjective recklessness was absent.

Involuntary intoxication is equally relevant to offences of basic intent because the basis of criminal liability for such offences is intention or recklessness as to a risk. If involuntary intoxication prevented the defendant from foreseeing the risk and unreasonably taking it, the mental element is not satisfied. If, however, the defendant’s conduct and state of mind demonstrate intention or subjective awareness of the risk, liability is not avoided merely because the intoxication was not self‑induced.

Care must be taken to distinguish any claim of involuntary intoxication from automatism. Where the impaired state arises from intoxication, ordinary intoxication rules apply; automatism is not available if the automatism results from intoxication. The decisive question remains whether mens rea was formed.

Voluntary Intoxication

Voluntary intoxication refers to situations where the defendant has knowingly consumed alcohol or drugs, or other intoxicating substances, where it is common knowledge that such substances may impair awareness or induce aggressive behaviour. This includes illegal drugs and alcohol, even if the defendant misjudges the strength or effect of the substance.

Key Term: Voluntary Intoxication
Intoxication resulting from the defendant's willing consumption of alcohol or drugs, where the intoxicating effect is known or reasonably expected.

The effect of voluntary intoxication depends crucially on the type of offence charged, specifically whether it is a crime of specific intent or basic intent. This distinction was established in DPP v Majewski.

There is also a relevant distinction between dangerous and non‑dangerous substances:

• Dangerous substances include alcohol and illegal drugs. Voluntary consumption is treated as reckless and will not assist where recklessness suffices for the offence.
• Non‑dangerous substances (e.g., prescription sedatives taken in therapeutic doses) are not ordinarily associated with aggressive or unpredictable behaviour. Where unexpected effects occur, the analysis aligns with involuntary intoxication provided the defendant was not reckless in taking them (Hardie). This can, in appropriate cases, assist a defendant even with basic intent offences if mens rea was absent.

Specific Intent Offences

These are offences where the definition of the crime requires proof of intention as the mens rea; recklessness is not sufficient. Examples include murder (intention to kill or cause GBH), wounding or causing GBH with intent (s.18 OAPA 1861), and theft (intention to permanently deprive).

Key Term: Specific Intent Offence
A crime where the mens rea requires proof of intention regarding one or more elements of the actus reus. Recklessness is insufficient.

Voluntary intoxication may be relevant to specific intent offences. If the defendant was so intoxicated that they were incapable of forming, and therefore did not form, the required specific intent, they cannot be convicted of that specific intent offence. However, they may still be convicted of a lesser, basic intent offence if one is available as an alternative. For example, a defendant charged with murder who successfully argues lack of specific intent due to voluntary intoxication may still be convicted of unlawful act manslaughter (a basic intent crime).

The inquiry is evidentially sensitive. Courts frequently direct juries that:

• they must consider whether, despite intoxication, the defendant actually had the specific intent required; and
• if the jury is sure the defendant did have that intent, intoxication provides no defence; if not sure, the specific intent charge fails, but an available lesser basic intent offence may be proved instead.

Illustrations:

• If a defendant voluntarily consumes alcohol and, in that state, commits s.18 GBH with intent, the question is whether the prosecution proves the specific intent to cause serious harm. If this is not proved due to incapacity to form intent, the defendant may nevertheless be guilty of s.20 GBH (where recklessness suffices).
• In R v Lipman, LSD‑induced hallucinations meant murder (specific intent) could not be proved, but unlawful act manslaughter (basic intent) was available.

The classification of “specific intent” is determined offence‑by‑offence and is shaped by policy. Theft, robbery, burglary with intent (s.9(1)(a)), conspiracy, attempts, murder, and s.18 GBH are treated as specific intent. Many sexual offences are treated as basic intent, and intoxication will not negate liability where recklessness suffices or where the statutory mental element eschews intoxication‑based mistakes.

Basic Intent Offences

These are offences where the mens rea can be satisfied by proof of either intention or recklessness. Examples include assault, battery, assault occasioning actual bodily harm (ABH), wounding or inflicting GBH (s.20 OAPA 1861), and unlawful act manslaughter.

Key Term: Basic Intent Offence
A crime where the mens rea can be satisfied by proof of either intention or recklessness regarding an element of the actus reus.

Voluntary intoxication is never a defence to a crime of basic intent. The reasoning, established in DPP v Majewski, is that the act of becoming voluntarily intoxicated is considered reckless conduct in itself. This recklessness is sufficient to satisfy the mens rea requirement for any basic intent offence committed whilst intoxicated.

Later decisions endorse a pragmatic approach: ask whether the defendant would have foreseen the relevant risk if sober. If yes, the mens rea is satisfied; voluntary intoxication does not assist. This approach is consistent with Coley, McGhee and Harris, and maintains the Majewski principle without mischaracterising intoxication evidence as the mens rea itself.

Two corollaries:

• Where a defendant confesses to intent (e.g., intending serious harm under s.18), intoxication is immaterial; intent is proved.
• Where the offence requires a reasonable belief (e.g., certain sexual offences), an intoxicated belief is unlikely to meet the reasonableness threshold; the sober standard is applied.

Strict liability offences do not involve mens rea, so intoxication is irrelevant to liability (though it may mitigate sentence).

Dutch Courage

A defendant cannot rely on voluntary intoxication if they deliberately consumed intoxicants to gain the courage to commit an offence (the 'Dutch courage' rule). In such cases, the necessary mens rea existed before the intoxication took effect (Attorney-General for Northern Ireland v Gallagher).

Dutch courage operates as an exception to any suggestion that incapacity at the moment of the act might save a defendant: where intent was formed while sober and intoxication was pursued to facilitate carrying it out, the prior wicked intent suffices.

Worked Example 1.1

David is charged with theft (a specific intent crime). He took a bicycle from outside a pub, genuinely believing it was his own identical bike. He had consumed six pints of strong lager beforehand. He argues he only made the mistake because he was drunk.

Is David likely to be able to rely on his intoxication?

Answer:
David's intoxication is voluntary. Theft requires dishonesty and an intention to permanently deprive. If David genuinely believed the bike was his, he lacked dishonesty (s.2(1)(a) Theft Act 1968) and the intention to permanently deprive the true owner. If his intoxication was the reason for his mistaken belief, and this prevented him from forming the necessary specific intent (dishonesty and ITPD), then his intoxication could potentially lead to an acquittal for theft. The key is whether he formed the mens rea despite the intoxication. If the jury is sure that, notwithstanding the drink, he did form the intention to appropriate property he knew was not his, intoxication will not assist. If they are not sure that intent was formed, the specific intent charge fails. There is no lesser basic intent theft offence, so absence of intent will result in acquittal on theft.

Intoxication and Other Defences

Voluntary intoxication can also impact a defendant's ability to rely on other defences, particularly those involving a mistaken belief.

If a defendant makes a mistake about the need to use force in self-defence due to voluntary intoxication, they cannot rely on that mistake. The defence of self-defence requires the defendant's belief in the need for force to be genuinely held, but an intoxicated mistake is not considered a valid basis (R v O'Grady; R v Hatton). This principle is now reflected in statute: s 76(5) of the Criminal Justice and Immigration Act 2008 provides that a mistaken belief attributable to voluntary intoxication cannot be relied on for the purposes of self‑defence or prevention of crime. The defendant is judged against the standard of a reasonable sober person.

Similarly, for certain offences (like many sexual offences), a reasonable belief in consent is required. An intoxicated mistaken belief in consent would not be considered reasonable. The test is objective on the question of reasonableness, and intoxication does not lower the standard.

By contrast, the statutory defence of lawful excuse under s 5(2) of the Criminal Damage Act 1971 can succeed on the basis of an honest belief, even if the belief was formed while intoxicated. This creates a limited but important exception to the general rule that intoxicated mistakes do not avail the defendant.

Key Term: Lawful Excuse
A statutory defence under s 5(2) Criminal Damage Act 1971 where a defendant honestly believes the owner consented or would have consented to the damage, or acted to protect property in certain specified circumstances. The belief need only be honestly held; its reasonableness is immaterial.

Practical implications:

• Self‑defence: intoxicated mistakes are excluded (CJIA 2008, s 76(5)). Pre‑emptive strikes and heat‑of‑the-moment latitude still apply, but not where the perceived threat comes from intoxication.
• Criminal damage lawful excuse: a drunken honest belief that the owner would have consented (or did consent) may succeed because the statute focuses on honesty, not reasonableness.
• Consent in offences against the person: the relevance of intoxicated mistaken belief depends on the offence definition. For ABH and battery, where consent can sometimes operate as a defence, courts look to the defendant’s actual belief. For sexual offences, the statute requires a reasonable belief in consent and intoxication does not help.

Recent case law has clarified that “attributable to intoxication” includes both mistakes formed while intoxicated and short‑term after‑effects (e.g., paranoia) immediately following intoxication (R v Taj). This ensures that defendants cannot side‑step the exclusion by claiming the mistaken belief arose slightly after consumption rather than during it.

Worked Example 1.2

Anna is involuntarily intoxicated after her drink was spiked at a party. Mistakenly believing Ben is about to attack her, she pushes him away, causing him to fall and suffer minor bruising (actus reus for battery, a basic intent crime).

Can Anna rely on her intoxication?

Answer:
Anna's intoxication is involuntary. Battery is a basic intent crime, requiring intention or recklessness as to applying unlawful force. If Anna's involuntary intoxication prevented her from forming either the intention to apply force or the recklessness as to applying force (because she genuinely believed she was acting in self-defence due to the intoxication), she may be acquitted of battery because she lacked mens rea. If, however, the evidence shows she intended to use force or foresaw the risk of applying unlawful force and unreasonably took that risk, her intoxication will not assist. The exclusion of intoxicated mistakes in self‑defence applies to voluntary intoxication; it does not bar Anna’s argument where intoxication was not her fault, but the decisive point remains whether mens rea was absent.

Exam Warning

A common point of confusion is the phrase 'drunken intent is still intent'. Remember that intoxication, even if voluntary, only provides a potential basis for negating mens rea if the defendant was incapable of forming the required intent. If, despite the intoxication, the defendant still formed the necessary specific intent (for a specific intent crime), they remain liable. For basic intent crimes, voluntary intoxication supplies the necessary recklessness.

Additional cautions:

• Classify the offence accurately: specific intent analysis is different from basic intent analysis, and the availability of lesser alternatives matters.
• Do not treat ignorance of strength as involuntary intoxication.
• Distinguish dangerous from non‑dangerous intoxicants: unexpected effects from non‑dangerous soporific drugs may align with involuntary intoxication if the defendant was not reckless.
• Intoxication does not assist with strict liability offences.
• For self‑defence, an intoxicated mistake (including short‑term after‑effects) is excluded where intoxication was voluntary.

Key Point Checklist

This article has covered the following key knowledge points:

• Intoxication is not a defence itself but may prevent the formation of mens rea.
• A distinction is drawn between voluntary and involuntary intoxication.
• A distinction is drawn between specific intent and basic intent crimes.
• Voluntary intoxication can only potentially negate the mens rea for specific intent crimes.
• Voluntary intoxication is never a defence to basic intent crimes (Majewski rule).
• Involuntary intoxication can potentially negate the mens rea for both specific and basic intent crimes.
• Intoxicated intent is still intent (Kingston).
• A defendant cannot rely on a mistake induced by voluntary intoxication for defences like self-defence (CJIA 2008, s 76(5)).
• Dangerous vs non‑dangerous intoxicants: unexpected effects of non‑dangerous medication can be treated akin to involuntary intoxication if not reckless (Hardie).
• Ignorance of the strength of an alcoholic drink does not convert voluntary intoxication into involuntary intoxication (Allen).
• Dutch courage: intent formed while sober cannot be neutralised by later intoxication (Gallagher).
• Intoxication is irrelevant to strict liability offences.
• Statutory lawful excuse for criminal damage can succeed on an honest belief even if formed while intoxicated.

Key Terms and Concepts

• Involuntary Intoxication
• Voluntary Intoxication
• Specific Intent Offence
• Basic Intent Offence
• Lawful Excuse