FE-1 Criminal Law key terms

The physical or external element of a crime: a voluntary act, omission, or state of affairs that the offence definition prohibits. It must be proved alongside the mental element, except in strict liability offences.

The mental element of an offence: the state of mind the prosecution must prove, such as intention, knowledge, recklessness, or negligence. It identifies the defendant's attitude toward the prohibited conduct or result.

Movement of the body directed by the will. Only voluntary conduct can ground criminal liability; reflexes, spasms, and movements during unconsciousness are not acts for this purpose.

A failure to act. Liability for an omission arises only where the law imposes a duty to act, for example through statute, contract, a special relationship, assumption of responsibility, or creation of a danger.

A legal obligation that turns a failure to act into the conduct element of an offence. Sources include statute, contract, family or other special relationships, voluntary assumption of care, and dangerous prior conduct.

The link between the defendant's conduct and the prohibited result. Factual causation asks whether the result would have occurred without the conduct; legal causation asks whether the conduct was an operating and substantial cause.

The factual causation test: would the result have happened when and as it did but for the defendant's conduct? If the answer is yes, factual causation is not established and the analysis ends there.

A new intervening act or event that breaks the chain of causation, so the defendant is not liable for the later result. It must be free, deliberate, and informed, or otherwise independent of the defendant's conduct.

The principle that a defendant must take the victim as found. An unexpectedly fragile condition that makes the victim die or suffer more serious harm does not break causation.

The most serious form of mens rea. Direct intention exists where the result is the defendant's aim or purpose; oblique intention exists where the result is a virtually certain consequence the defendant appreciates.

Awareness of a risk that the prohibited result will occur or the prohibited circumstance exists, together with unreasonable taking of that risk. Subjective recklessness requires proof the defendant actually foresaw the risk.

A failure to exercise the degree of care a reasonable person would exercise in the circumstances. In criminal law it is measured objectively and usually suffices only for specific offences such as gross negligence manslaughter.

Actual awareness that a fact exists or that a consequence will follow. It is a higher threshold than recklessness because it requires certainty in the defendant's mind rather than mere foresight of risk.

Deliberately avoiding information that would confirm a fact the defendant suspects, so as to preserve deniability. Courts may treat this as equivalent to knowledge for offences requiring awareness of a circumstance.

The reason a person commits an offence, such as greed, jealousy, or revenge. Motive is generally irrelevant to liability once the conduct and mental elements are proved, though it may be relevant to sentencing.

An offence for which the prosecution need not prove any mental element as to at least one element of the actus reus. Defences such as mistake may still be available if the statute allows them.

An offence requiring no mental element at all and allowing no defence of mistake or due diligence. Liability follows automatically once the prohibited conduct is proved.

The interpretive starting point that Parliament intends a mental element to be required for every element of an offence. It can be displaced only by clear words or the necessary implication of the statute.

Where the defendant intends to harm one person or object but accidentally harms another, the intention transfers to the actual victim. It applies only where the two harms share the same offence definition.

The requirement that the mental element be present at some point during the conduct causing the result. A later-formed intention cannot retrospectively make earlier innocent conduct criminal.

A doctrine treating a course of conduct as one act, so that mens rea formed partway through still coincides with the actus reus. It is often applied to unlawful detention or possession.

Involuntary behaviour caused by an external factor such as a blow, medication, or illness, where the defendant has no control over the movements. It negates the voluntary act and results in acquittal.

A defence based on a disease of the mind causing a defect of reason that leaves the defendant unable to know the nature of the act or that it was wrong. It results in a special verdict rather than ordinary acquittal.

A state caused by alcohol, drugs, or other substances. Involuntary intoxication may negate mens rea for specific intent offences; voluntary intoxication is generally no defence to basic intent offences.

An offence requiring proof of intention as to the prohibited result, such as murder or theft. Voluntary intoxication may provide a defence because the defendant could not form the required intention.

An offence that can be committed recklessly as to the prohibited result, such as assault or manslaughter. Voluntary intoxication is no defence because becoming intoxicated is itself reckless.

A genuine belief in facts that, if true, would remove a required element of the offence. A mistake of fact may negate mens rea; a mistake of law generally does not.

The use of reasonable force to protect oneself or another from an imminent unlawful attack. The force must be necessary and proportionate; a mistaken belief in the need for force may be considered if honestly held.

A defence where the defendant commits an offence because of a threat of death or serious harm that a reasonable person of ordinary firmness could not resist. It is unavailable to murder and some other offences.

A defence of last resort where the defendant commits an offence to avoid a greater evil, with no realistic alternative. It is narrow, rarely succeeds, and is not available to murder.

An offence committed when the defendant does an act more than merely preparatory to a target offence with the intention of committing it. Impossibility of completion is generally no bar to liability.

The conduct threshold for attempt. Courts ask whether the defendant had actually embarked on the crime, distinguishing preparatory steps such as reconnaissance from the commencement of the offence itself.

An agreement between two or more people to pursue a course of conduct that will necessarily involve the commission of an offence. The agreement itself is the offence, whether or not it is carried out.

Liability of a secondary party who aids, abets, counsels, or procures an offence committed by another. The accessory must intend to assist or encourage and the principal must commit the offence.

A form of complicity where two or more people share a common criminal purpose and one commits a further offence in the course of it. Liability depends on foresight of what the principal might do.

Communication of a clear and unequivocal intention to cease participation, made in time and in a manner that can reasonably prevent the offence. It ends liability as an accessory.

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

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

Unlawful killing caused by a breach of duty of care that was grossly negligent and contributed substantially to death. The conduct must be so bad as to justify criminal conviction.