Learning Outcomes
This article examines the main defences available to a charge of criminal damage under the Criminal Damage Act 1971 and how they interface with the wider framework of criminal law defences tested on SQE1. It explains the statutory defence of lawful excuse under s 5, breaking down its subjective and objective elements, and comparing belief in consent with protection of property under s 5(2)(a) and (b), including the effect of honest but unreasonable mistake, intoxication-induced belief, and the distinction between simple and aggravated damage. It further examines the operation of general defences in criminal damage scenarios—self-defence (including defence of property and prevention of crime), intoxication, consent, duress, and necessity—emphasising their theoretical basis, availability to simple and aggravated offences, and the respective evidential and legal burdens. The article highlights how actus reus and mens rea interact with these defences, focusing on thresholds of immediacy, reasonableness, necessity, and proportionality. It also reviews key case law and typical problem-question patterns so that readers can accurately identify, structure, and evaluate potential defences, assess whether they are realistically arguable on the facts, and apply them with the precision required in SQE1 single best answer questions and written client-focused advice.
SQE1 Syllabus
For SQE1, you are required to understand defences to criminal damage under the Criminal Damage Act 1971, including the statutory defence of lawful excuse and the interaction with general defences and procedure, with a focus on the following syllabus points:
- The statutory defence of lawful excuse under s 5 CDA 1971, including all elements of honest belief in consent and protection of property, and the balance between subjective and objective tests.
- The application and limits of lawful excuse as it relates to simple criminal damage versus aggravated criminal damage and arson.
- Practical and legal distinctions between actual and hypothetical consent, and how belief must be formed and substantiated.
- The intersection and incompatibility of lawful excuse with general defences: self-defence, intoxication (voluntary and involuntary), consent, duress, and necessity. This includes their availability to aggravated offences and requirements for their establishment.
- The procedural requirements for raising a defence (evidential burden), the prosecution’s legal burden of proof, and the standard to be met (beyond reasonable doubt or balance of probabilities if the burden is reversed by statute).
- Detailed understanding of evidential issues: admissibility of evidence relating to belief, character, circumstances, and expert reports, consistent with the operation of the CrimPR and PACE.
- Procedural and professional conduct implications for solicitors, including disclosure, instructions, and the handling of conflicts of interest where defence is to be advanced.
- The significance of defences in sentencing and the impact of mitigation arising from honest mistake or partial defenses.
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.
-
Which section of the Criminal Damage Act 1971 provides the defence of lawful excuse?
- Section 1(1)
- Section 1(2)
- Section 5
- Section 10
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A defendant honestly, but unreasonably, believes the owner would consent to damage caused to their property. Can they rely on lawful excuse under s 5(2)(a) CDA 1971?
- Yes, if the belief is honestly held.
- No, the belief must be reasonable.
- No, belief in consent is never a defence.
- Yes, but only if the defendant was not intoxicated.
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Can the defence of lawful excuse under s 5 CDA 1971 be used for a charge of aggravated criminal damage (s 1(2) CDA 1971)?
- Yes, always.
- No, never.
- Yes, but only the 'belief in consent' part.
- Yes, but only the 'protection of property' part.
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A defendant damages property belonging to another while heavily intoxicated voluntarily. They claim they lacked the mens rea due to intoxication. Is this a valid defence to simple criminal damage?
- Yes, intoxication always negates mens rea.
- No, voluntary intoxication is never a defence to basic intent crimes like simple criminal damage.
- Yes, if the intoxication meant they could not form the specific intent required.
- No, intoxication is only relevant if it was involuntary.
Introduction
When a defendant is charged with a criminal damage offence under the Criminal Damage Act 1971 (“CDA 1971”), whether simple criminal damage, aggravated criminal damage, or arson, defences may be available to avoid or reduce criminal liability. The statutory framework under the CDA 1971 is unique in providing a specific defence of 'lawful excuse' for simple criminal damage and arson. Alongside this are general defences—such as self-defence, intoxication, consent, duress, and necessity—that may also be advanced, albeit with certain restrictions in the context of criminal damage. The scope, requirements, and effect of these defences differ markedly between simple and aggravated forms of criminal damage. Since criminal damage offences commonly arise in practice and can entail significant legal distinctions, a detailed understanding of the requirements, limits, and strategy for raising these defences is essential for the SQE1 and for effective client advice.
Key Term: Lawful Excuse
A specific statutory defence under s 5 of the Criminal Damage Act 1971, potentially negating liability for simple criminal damage or simple arson. Lawful excuse may arise where the defendant honestly believes in consent or acts to protect property, subject to defined tests.
Lawful Excuse (Section 5 CDA 1971)
The statutory defence of lawful excuse is provided by section 5 of the CDA 1971, carefully delineating its availability and operation within the law of criminal damage. First and foremost, the defence applies exclusively to offences under section 1(1): that is, simple criminal damage and simple arson. It is not a defence to aggravated criminal damage or aggravated arson under s 1(2), nor does it generally extend to criminal threats to destroy property or possession of articles for damage. There is, however, a strong practical overlap with general defences that may apply to aggravated offences.
The structure, language, and leading authorities on section 5, especially Jaggard v Dickinson [1981] QB 527 and R v Hunt [1977] 1 WLR 607, are critical for distilling the details of this statutory defence.
Section 5(2) anchors lawful excuse on two main alternative grounds:
- Honest belief in consent (s 5(2)(a))
- Acting to protect property belonging to self or another (s 5(2)(b))
In both cases, s 5(3) makes clear that belief is judged by a subjective test: what matters is the defendant’s state of mind, not the objective reasonableness of that belief. However, there are distinct requirements and limits within each limb.
Belief in Consent (s 5(2)(a))
Where the defence is based on belief in consent, lawful excuse is made out if, at the relevant time, the defendant believed that the person or persons entitled to consent to the destruction or damage had consented or would have consented had they known of all the circumstances.
This is interpreted entirely subjectively: it is irrelevant whether the belief in consent is reasonable, provided it is genuinely held. The principle stands even if the belief was induced by a mistake of fact (including identity, ownership, or circumstances), or by voluntary intoxication—a unique exception within criminal law. Case law, especially Jaggard v Dickinson, confirms the breadth of this subjective standard.
The person whose consent is relied upon must be someone with the proprietary interest (ownership, custody, or control) over the property. If the defendant honestly, albeit unreasonably, believes this, the defence may still be available—even if consent is not actually forthcoming or, had all facts been known, would not be granted.
The defence is not available if the belief is so fanciful as to be disbelieved (that is, not actually held). The presence of evidence to support the genuineness of the belief is important for making the issue 'live' in the trial.
Worked Example 1.1
Aisha, after a night of drinking, finds herself locked out of what she thinks is her friend's house and smashes a window to get in, sincerely believing her friend would 'definitely' approve if she knew the situation. It transpires it is in fact her neighbour's house.
Answer:
Aisha can rely on lawful excuse if she honestly believed, through drunken mistake, that her friend would have consented. The test is subjective; her mistaken, even intoxicated, belief satisfies s 5(2)(a) if it was truly held.
Beyond the main scenario of mistaken identity or ownership, the subjective belief can cover other circumstances—such as misapprehensions about the extent of consent or conditions the owner would have imposed. Still, belief induced by a legal mistake (about who the law says is entitled to consent) may not be sufficient.
Crucially, evidence of voluntary intoxication does not disqualify the belief, as confirmed by Jaggard v Dickinson, but awareness that this is a unique exception—it does not apply to defences of self-defence or duress, nor to the mens rea of basic intent offences more generally.
Exam Warning
Do not confuse the subjective approach for lawful excuse (s 5) with other defences, such as self-defence or mistake, which have subjective and objective elements. For s 5(2)(a), the defendant's honestly held belief (not its reasonableness) is determinative.
Acting to Protect Property (s 5(2)(b))
A separate head of lawful excuse, and the root of many practical cases, is found in s 5(2)(b): where the act is done to protect property, with a genuine belief in the urgent need for protection and that the means adopted are reasonable.
The essential requirements are:
- The defendant's purpose must be the protection of property (though not persons: R v Baker & Wilkins [1997] Crim LR 497).
- At the time of the act, the defendant must honestly believe that the property (their own or another's) was in immediate need of protection.
- The means used to protect the property must be honestly believed to be reasonable, though the means must also be objectively capable of achieving the end sought (R v Hunt).
Section 5(3) indicates that, again, the relevant beliefs (regarding risk and appropriateness of action) are subjective: it is whether the defendant honestly believed the property required immediate protection and that their actions were appropriate. However, the law imposes an additional check: the means employed must be, in reality, capable of (even if not guaranteed to) protecting the property as intended.
The property at risk must be property within the meaning of the Act—not people, nor property under speculative or long-term future threat. There must be an immediacy to the risk: vague suspicions or general prevention motives do not suffice.
Worked Example 1.2
Lena, seeing severe weather and believing a neighbour's weak fence is about to collapse on her classic car, damages the neighbour’s gate to create an escape path. She honestly believes her actions are necessary and reasonable. The weather turns and no damage occurs.
Answer:
Lena could rely on lawful excuse if the risk to property was immediate and she honestly believed the steps were necessary and reasonable in the circumstances, provided that the action taken was, objectively, of a kind capable of protecting property.
Situations where a risk is anticipated but not imminent—for instance, replacing a lock due to concerns about general neighbourhood crime—will likely not satisfy lawful excuse. Likewise, where the means used are wholly disproportionate, and not capable of protective effect, the objective element will fail (see R v Hunt).
Where the object of protection is unclear or the means too indirect for any rational connection with property protection, s 5(2)(b) will not be available.
Worked Example 1.3
Marcus damages a shed window to thwart suspected thieves whom he believes to be hiding inside, acting out of concern for a friend's property. He finds no one inside, and the report of theft turns out to be mistaken.
Answer:
Marcus may avail himself of the defence, provided his genuine and immediate belief about the threat to property and the appropriateness of his response, and that smashing the window was objectively a protective act—a connection the court must scrutinise.
Revision Tip
Distinguish: s 5(2)(a) centers on the defendant’s subjective belief in consent; s 5(2)(b) requires a subjective belief as to immediacy and need, but imposes an objective requirement that the acts are capable of property protection.
The Structure of the Lawful Excuse Defence
For lawful excuse under either s 5(2)(a) or (b):
- The defence only bears an evidential burden; they need only adduce some evidence raising the defence.
- If the judge is satisfied that an issue arises, the burden of proof then rests on the prosecution, who must disprove the defence beyond reasonable doubt.
- Care is needed to identify under which head of s 5 the defence is raised, since the factual matrix and case law support are different.
Limits and Boundaries of Lawful Excuse
- Lawful excuse is not available as a defence to aggravated criminal damage (s 1(2)), aggravated arson, threatening to destroy/damage property, or possession of articles with intention to damage.
- It requires a genuine (honest) belief on the part of the defendant, but not necessarily a reasonable or commonly held one; the mere fact of unreasonableness does not prevent reliance if the belief is genuine.
- Where the belief as to consent or property risk is so fanciful or unsupported that the jury cannot accept it is genuinely held, the defence falls.
- Lawful excuse under s 5(2)(b) is not available if the defendant acts only to protect persons or out of moral (rather than legal or proprietary) concern.
- The objective component (that the means are capable of protection) is an essential safeguard; efforts that are irrational or unrelated to property safety are not excused.
- S 5 does not permit protective or consent-based action for speculative or future risks, only for immediate threats.
- Damage solely to prevent a perceived harm to persons does not attract protection—see R v Baker & Wilkins.
- Lawful excuse is strictly limited to basic criminal damage and arson. Its omission from aggravated charges under s 1(2) reflects the seriousness and broader risk these offences present.
Worked Example 1.4
Peter smashes a car window to save a dog he honestly believes is about to die from heatstroke. Can he rely on lawful excuse?
Answer:
S 5(2)(b) does not protect action taken solely to protect animals or people; however, if the act is genuinely to protect property (if, for example, the dog's value as property is emphasised), it may fit the defence. In practice, emergency animal rescue may more often plead necessity.
General Defences and Criminal Damage
Beyond lawful excuse, the wider defences of criminal law may reduce or exclude liability, particularly when statutory excuse is unavailable (as for aggravated damage), or where the facts do not justify a lawful excuse finding. Their availability, requirements, and limits in criminal damage cases are summarised below.
Self-Defence
A defendant may rely on the general defence of self-defence (whether at common law, under s 3 Criminal Law Act 1967 on prevention of crime, or under s 76 Criminal Justice and Immigration Act 2008), if the damage to property was the honestly believed and proportionate response to an immediate threat, to protect self, others, or property, or to prevent a crime.
Key Term: Self-Defence
The general defence that allows a person to use reasonable force to defend themselves, another, or property, or to prevent crime, as judged primarily by their honest perception and subject to an objective assessment of the force used.
The essential conditions are:
- The force (including damage) must be used only where necessary, as honestly perceived by the defendant, even if mistaken (unless due to voluntary intoxication).
- The use of force must be reasonable in the circumstances as the defendant perceived them, weighing proportionality, immediacy, and the alternatives available.
- The force must be used in the defence of people or property, or to prevent or stop a crime; force for other motives will not suffice.
- Mistaken beliefs about necessity, if genuinely held and not arising from voluntary intoxication, can form the basis for the defence.
Worked Example 1.5
Thomas hears screams for help, sees a house on fire, and breaks down the door to effect a rescue, intending both to save life and prevent destruction. He is charged with criminal damage.
Answer:
Self-defence (or more accurately, defence of another and property) is likely available, provided the force used (breaking the door) was necessary and reasonable in the circumstances as Thomas honestly believed, and not grossly or disproportionately excessive.
The court will consider the necessity, urgency, and amount of force, as well as whether non-violent alternatives existed.
The householder defence under s 76 CJIA 2008 allows greater latitude in cases where the defendant uses force in a dwelling to resist a trespasser—force which is disproportionate (but not grossly so) may be allowable in this context for defending self or others, but this does not extend to protection of property alone.
Intoxication
Key Term: Intoxication
The condition of being under the influence of alcohol or drugs. Its effect on criminal liability depends on whether it was voluntary or involuntary and whether the offence is of basic or specific intent.
- Simple criminal damage is a basic intent offence. Voluntary intoxication does not amount to a defence, because recklessness in becoming intoxicated is treated as sufficient foresight of risk for these purposes (DPP v Majewski [1977]).
- Involuntary intoxication (such as through spiking) may potentially amount to a defence to both basic and specific intent offences, but only if it genuinely prevents the formation of the required mens rea at the material time.
- For aggravated criminal damage (a specific intent offence, given the requirement to intend or be reckless as to endangerment to life), voluntary intoxication may potentially preclude a conviction if the jury is not satisfied the defendant formed the requisite subjective intent.
- Exception for mistaken belief and lawful excuse: Under the unique statutory regime of s 5(2)(a), a defendant may rely on a belief in consent as a lawful excuse even if that belief is induced by voluntary intoxication (per Jaggard v Dickinson). This is not true for mistakes as to the necessity of force in self-defence (where voluntary intoxication will prevent reliance on the defence; see R v O'Grady [1987]).
Worked Example 1.6
Charlie, intoxicated, damages a door believing (unreasonably and drunkenly) that his landlord would have consented. The landlord says he would not.
Answer:
Provided the belief was honestly held, Charlie can rely on s 5(2)(a), even though the belief is induced by intoxication. He cannot, however, rely on intoxication otherwise to negate the mens rea for basic criminal damage.
Consent
Key Term: Consent
In the context of criminal damage, a valid, informed agreement by a person with the proprietary interest that their property may be damaged or destroyed. Consent negatives the unlawful element of damage.
The law recognises actual consent as a complete defence to criminal damage—if the person with the requisite proprietary interest knowingly and freely agrees to the act, there is no offence. If consent is given fraudulently or without proper understanding, it may be invalid. Where consent is given under a mistake, the effect depends on the nature of the mistake (identity, quality, circumstances).
For basic criminal damage, a belief—however mistaken but honestly held—in hypothetical or actual consent is sufficient (see above).
Comparison: Consent as a defence to offences against the person is narrowly circumscribed, with limits as to the harm which may be consented to and the purpose of the contact. In property offences, the categories of accepted consent are broader—the main restriction is proof of ownership or a right to authorise.
Duress and Necessity
Key Term: Duress
A general defence which may excuse a defendant who acts to avoid death or serious injury in response to a direct threat, where a person of reasonable firmness would have acted similarly and the situation was not one the defendant created by own fault.Key Term: Necessity
A defence invoked when a person commits an offence to avert a grave, imminent harm, with no lawful alternative, acting proportionately to avert that harm.
Duress applies broadly to all crimes except murder, attempted murder, and some forms of treason. It is sometimes raised in criminal damage, especially aggravated forms, but is stringently defined by the courts. The elements are:
- A threat of immediate or near-immediate death or serious injury against the defendant, their family, or someone for whom they are responsible.
- The defendant's resistance to the threat must be overborne at the time of the offence.
- The harm threatened must outweigh the harm caused.
- The defendant must not have placed themselves voluntarily in a situation likely to subject them to such threats.
- The test is both subjective and objective: actual threat, honest belief (even if mistaken), and the action of a reasonable person.
Necessity is only very rarely admitted, where the crime is committed to avoid an unavoidable and irreparable harm, and only if the means used are strictly proportionate and no lawful alternative exists (see Re A (Children) [2000]). Necessity remains a controversial and tightly circumscribed defence. In property offences, courts are wary of over-extending the defence lest it invite vigilante behaviour.
Worked Example 1.7
Arun is threatened with death unless he spray paints anti-government slogans on a public building. He believes the threat is immediate and real. Police arrest him as he finishes.
Answer:
Duress may provide a complete defence if all elements are strictly satisfied: there must be an immediate threat of serious harm, no avenue of escape, and the crime must not be one for which duress is excluded. The court will scrutinise whether Arun’s will was truly overborne.
Necessity may be invoked if property is damaged to save life or avert imminent harm and there was no practical alternative, but the courts are very slow to accept the defence.
Application to Aggravated Offences
A critical limitation of lawful excuse is that it does not apply to aggravated criminal damage or aggravated arson charges. Here, general defences are the only available route for exculpation—self-defence (e.g., breaking in to save life where property is not solely at risk), duress, and necessity. These are subject to more stringent scrutiny, given the nature of the harm and the seriousness of the offence charged. The courts consistently require that the threshold for these defences be met in full, with particular caution as to proportionality and immediacy.
Worked Example 1.8
Miranda, to prevent a group of protestors from causing catastrophic damage by sabotaging power lines, damages a padlock and disables a fuse box, acting in a perceived emergency.
Answer:
Lawful excuse would only apply if the means were aimed at protecting property under immediate threat, were objectively capable of doing so, and Miranda acted on an honestly held belief. Were her acts aimed at preventing aggravated criminal damage (e.g., endangerment to life), only a general defence (e.g., necessity, if strict criteria are met) would be available.
Professional Conduct and Procedural Implications
Legal advisers must be vigilant to their duties under the SRA Code of Conduct and the Criminal Procedure Rules when advising on or advancing defences to criminal damage. Where a client plans to plead not guilty, asserting a defence such as lawful excuse, self-defence, or duress, the solicitor should ensure the factual basis supports at least an evidential issue to properly raise the defence. If a client privately admits guilt but pursues a not guilty plea, the solicitor should put the prosecution to proof but must not mislead the court or assist in the presentation of untruthful evidence. If the client wishes to give evidence that the solicitor knows to be false, the solicitor must withdraw and cannot reveal the reason for withdrawal to the court.
Where co-defendants are involved and conflicting defences are anticipated, the solicitor should carefully assess for any conflict of interest or potential breach of confidentiality, acting in accordance with professional rules.
Solicitors should also ensure that information relevant to the defence is disclosed in compliance with the Criminal Procedure and Investigations Act 1996 and the Criminal Procedure Rules, providing advance notice to the prosecution and court where required (for instance, with formal notices relating to special defences).
The proper conduct of case management includes ensuring that any substantive defence is disclosed in time for the court and prosecution to make appropriate case management directions or to admit relevant evidence. Factual admissions, written statements, and advance information from the client should be handled diligently and in strict compliance with conduct rules.
Summary
- Lawful excuse under s 5 CDA 1971 is a focused defence exclusive to simple criminal damage and simple arson, available where the defendant honestly believes in consent or is genuinely acting to protect property in immediate need of protection, subject to both subjective and objective requirements.
- The honest belief in owner consent (s 5(2)(a)) operates on a purely subjective basis—any sincerely held belief, no matter how unreasonable or induced by intoxication, may suffice if genuinely held.
- Under s 5(2)(b), the belief in property protection must also be genuine, and the means adopted must be objectively capable of achieving that aim; speculation or indirect measures will not suffice.
- Lawful excuse cannot be relied upon as a defence to aggravated criminal damage or aggravated arson, which may endanger life.
- General defences (self-defence, intoxication, consent, duress, necessity) may operate instead, with their own strict criteria and evidential and legal burdens.
- Voluntary intoxication is not generally a defence to basic intent offences such as simple criminal damage but may be relevant in rare cases of lack of intent, or (under s 5(2)(a)) to belief in consent.
- The actual, valid consent of the owner (competently given and not vitiated by fraud or incapacity) is always a defence to criminal damage.
- Duress and necessity are available in only limited situations, requiring immediate, inescapable threat or unavoidable harm, and are not available to all charges (notably murder, attempted murder, and some forms of treason).
- The evidential burden to raise the defence lies with the defendant; once the defence is 'live', it is the prosecution's duty to prove beyond reasonable doubt that the defence does not succeed.
- Counsel must observe all professional and ethical duties when advising clients, procuring evidence, and advancing defences in accordance with the Criminal Procedure Rules and SRA Code of Conduct.
Key Point Checklist
This article has covered the following key knowledge points:
- The statutory defence of lawful excuse under s 5 CDA 1971 is exclusive to simple criminal damage and simple arson.
- Lawful excuse can arise from the defendant's honest belief in owner consent (s 5(2)(a)) or an honest belief in the need to protect property (s 5(2)(b)), each with structured subjective and objective requirements.
- The subjective test for s 5(2)(a) is broad: any honestly held belief may suffice, including those arising from voluntary intoxication or wild mistake.
- For s 5(2)(b), the belief in need and the means must be honestly held, but the means chosen must be judged objectively for their capacity to protect property at risk.
- Lawful excuse is not available as a defence to aggravated criminal damage or aggravated arson, given the element of danger to life.
- General defences—self-defence, intoxication, consent, duress, necessity—apply with strict legal and evidential limits and will frequently be scrutinised for necessity, proportionality, and immediacy.
- Voluntary intoxication may only preclude conviction for specific intent offences (such as aggravated criminal damage) where the requisite mental state is genuinely not formed.
- Valid, informed consent from the person with proprietary interest is a complete defence; vitiating factors (deception about the act or identity, incapacity) will defeat consent.
- Duress and necessity are available only exceptionally and require clear and persuasive evidence; the proportionality of response is always relevant.
- The defendant bears only the evidential burden for lawful excuse and most general defences; the legal burden to disprove or negate the defence remains with the prosecution to the criminal standard.
- Conduct obligations under the SRA Code of Conduct and the Criminal Procedure Rules are essential when preparing and running defences.
Key Terms and Concepts
- Lawful Excuse
- Self-Defence
- Intoxication
- Consent
- Duress
- Necessity
Key Term: Lawful Excuse
A statutory defence (s 5 CDA 1971) excusing basic criminal damage or simple arson where a defendant genuinely believes in consent or is acting to protect property believed to be in immediate need of protection, with subjective and objective requirements depending on the ground relied on.Key Term: Self-Defence
A general defence encompassing the use of reasonable, necessary force in protection of self, others, property, or the prevention of crime; force must be necessary and proportionate as judged in the circumstances as the defendant believed them to be, unless that belief is induced by voluntary intoxication.Key Term: Intoxication
The condition of being under the influence of drink or drugs. Voluntary intoxication is not a defence to basic intent offences (e.g., simple criminal damage); involuntary intoxication may be, if it precludes the formation of mens rea. Intoxication may, uniquely in criminal damage, ground an honestly held belief for lawful excuse under s 5(2)(a).Key Term: Consent
Owner authorisation for their property to be damaged or destroyed. Where consent is valid and competent, there is no offence. The defence can also arise via an honestly held belief in hypothetical consent under s 5(2)(a).Key Term: Duress
A general defence available where a person commits an offence in response to an immediate threat of death or serious injury to themselves or another whom they reasonably feel responsible for, provided the threat is not self-induced and the harm caused is proportionate and unavoidable.Key Term: Necessity
A rarely accepted general defence where the offence is committed to avert an unavoidable, irreparable harm in circumstances of real and pressing emergency, with no lawful alternative.