NG Bar Part I Criminal Law key terms

The external, physical element of an offence: the prohibited conduct, its circumstances, and any consequence required by the definition. It must be proved by the prosecution and is distinct from the defendant's mental state.

The mental element of an offence, such as intention, recklessness, knowledge, or negligence. It describes the state of mind the definition requires in relation to the actus reus and must be proved for each element.

The highest form of mens rea. Direct intention exists where the defendant aims at or desires the result; oblique intention may be found where the result is a virtually certain consequence of the defendant's conduct and the defendant appreciates that fact.

A form of mens rea in which the defendant consciously takes an unjustified risk that a circumstance exists or a consequence will occur. It requires awareness of the risk, not mere carelessness, in most modern formulations.

A failure to exercise the degree of care that a reasonable person would exercise in the circumstances. Criminal negligence is a lower fault standard than recklessness and is used in some offences such as gross negligence manslaughter.

An offence for which the prosecution need not prove mens rea as to one or more elements of the actus reus, usually regulatory or public welfare offences. Defences such as mistake may still be available in limited circumstances.

An offence that requires no mental element at all and permits no defence of mistake, even a reasonable one. Courts interpret statutory language strictly before concluding that Parliament intended to exclude mens rea entirely.

Liability for failing to act, which arises only where the law imposes a duty to act. Duties may arise from statute, contract, a special relationship, voluntary assumption of care, or creation of a dangerous situation.

A legal obligation that converts a failure to act into the conduct element of an offence. Sources include statutory duties, contractual duties, family relationships, assumption of responsibility, and the defendant's own creation of a risk.

A doctrine imposing a duty to act on a person who innocently or otherwise creates a dangerous situation. Once the danger exists, the person must take reasonable steps to avert harm, and failure may found liability.

The link between the defendant's conduct and the prohibited result. It has two limbs: factual causation, usually tested by the 'but for' question, and legal causation, which asks whether the defendant's conduct was an operating and substantial cause.

The 'but for' test: the result would not have occurred when and as it did but for the defendant's conduct. It is a necessary but not sufficient condition for liability and is always followed by an assessment of legal causation.

A new intervening act or event that breaks the chain of causation, so the defendant is not liable for the result. Examples include independent acts of third parties or the victim, and certain extraordinary natural events.

The principle that a defendant must take the victim as found, including any physical or psychological vulnerability. An unexpected degree of harm caused by a pre-existing condition does not break the chain of causation.

Conduct by the victim that may break the chain of causation. It generally does not do so unless the victim's response was so disproportionate or independent that it is not a foreseeable consequence of the defendant's conduct.

The unlawful killing of a human being under the Queen's peace with malice aforethought. Malice aforethought means an intention to kill or an intention to cause grievous bodily harm, and the mandatory sentence is life imprisonment.

The mens rea of murder. It is satisfied by an intention to kill or an intention to cause really serious bodily harm, and it need not involve ill will or premeditation despite the traditional label.

A killing that would otherwise be murder but is reduced because of a partial defence: loss of control, diminished responsibility, or suicide pact. The defendant is convicted of manslaughter and the judge has sentencing discretion.

An unlawful killing without malice aforethought. The main forms are unlawful act manslaughter, gross negligence manslaughter, and reckless manslaughter, each with distinct elements and fault requirements.

A form of involuntary manslaughter requiring an intentional unlawful act, dangerous in the sense that a sober and reasonable person would foresee a risk of some physical harm, which causes death. The act must be a crime in itself.

Involuntary manslaughter based on a breach of duty of care that caused death and was so grossly negligent as to be criminal. The breach must be serious enough to justify a criminal conviction.

A partial defence reducing murder to manslaughter where the defendant lost self-control because of a qualifying trigger and a person of the defendant's sex and age with a normal degree of tolerance would have reacted similarly.

A partial defence to murder based on an abnormality of mental functioning arising from a recognised medical condition that substantially impaired the defendant's capacity to understand conduct, form a rational judgment, or exercise self-control.

A former partial defence to murder, now replaced in many jurisdictions by loss of control. It addressed sudden loss of self-control caused by the victim's conduct and reduced murder to manslaughter.

A general defence based on a disease of the mind causing a defect of reason such that the defendant did not know the nature and quality of the act or did not know it was wrong. It results in a special verdict.

A defence of total loss of voluntary control brought about by an external factor such as a blow to the head or medication, not a disease of the mind. The defendant is treated as not acting at all.

A defence based on voluntary or involuntary consumption of substances. Involuntary intoxication may negate mens rea; voluntary intoxication may negate specific intent offences but generally not basic intent offences.

An offence requiring proof of a particular intention, such as murder or theft. Voluntary intoxication may be a defence where it prevents the defendant from forming that specific intent.

An offence whose mens rea can be satisfied by recklessness, such as assault. Voluntary intoxication is generally no defence because becoming intoxicated is itself regarded as reckless.

A complete defence to a criminal charge where the defendant used reasonable force to protect themselves or another from an imminent threat. The force used must be proportionate to the threat as perceived.

The amount of force employed in self-defence or prevention of crime. It must be reasonable in the circumstances as the defendant honestly believed them to be, with allowance for a person acting in the heat of the moment.

A defence where the defendant was compelled to commit an offence by threats of death or serious injury. The threat must be imminent, and a person of reasonable firmness would have acted as the defendant did.

A defence of last resort where the defendant acted to avoid a greater evil in circumstances of imminent danger. It is limited, unavailable to murder, and requires that no reasonable alternative course was available.

A defence where the defendant commits an offence because of pressing circumstances rather than a human threat, such as breaking into a building to escape danger. The same proportionality and imminence requirements apply.

An inchoate offence committed where the defendant does an act more than merely preparatory to the commission of an offence with the intention of committing it. The substantive offence need not be completed.

A crime that is preliminary to or incomplete as to the substantive offence, such as attempt, conspiracy, or incitement. Liability arises from the preparatory conduct rather than the completed harm.

An inchoate offence involving an agreement between two or more persons to pursue a course of conduct that will necessarily amount to a crime. The agreement itself is the actus reus.

The dishonest appropriation of property belonging to another with the intention permanently to deprive. Each element must be proved, and dishonesty is assessed under the applicable statutory or common law test.

An assumption of the rights of the owner of property, such as taking, using, selling, or destroying it. It can occur even where the property came into the defendant's hands innocently.

The fault element of theft and fraud, assessed under a two-stage test asking whether the conduct was dishonest by ordinary standards of reasonable and honest people and whether the defendant knew it was.

Theft committed with the use or threat of force immediately before or at the time of stealing, in order to steal. The force must be used in order to steal and must be more than minimal.

Entering a building or part of a building as a trespasser with intent to commit theft, grievous bodily harm, or criminal damage, or committing such an offence after entering. It may be charged under statute in several forms.

An offence committed by dishonestly making a false representation, failing to disclose information where there is a duty to do so, or abusing a position of trust, with intent to gain or cause loss.

An act causing the victim to apprehend immediate unlawful personal violence. The mens rea is intention or recklessness as to causing that apprehension, and no physical contact is required.

The unlawful application of force to another person. The force may be minimal, and the mens rea is intention or recklessness as to applying unlawful force, not necessarily as to causing harm.

An offence of assault occasioning bodily harm that is more than transient or trifling, such as bruising or a broken tooth. It requires proof that the assault or battery caused the harm.

Really serious bodily harm, including serious psychiatric injury. It may be charged as an offence of maliciously causing grievous bodily harm with intent or of inflicting it unlawfully and maliciously.

A person who enters premises without permission or exceeds the permission given. In burglary, the defendant must know or be reckless as to the lack of consent to enter.

The reason a person acts, such as greed, jealousy, or revenge. Motive is generally irrelevant to criminal liability, which turns on the defined actus reus and mens rea rather than the defendant's underlying purpose.

A procedural question of whether a defendant can understand the charge, instruct counsel, and follow proceedings. Unfitness stays the trial and may lead to a finding of not guilty by reason of insanity or a supervision order.