NCA Criminal Law key terms

The physical or external component of a crime: a voluntary act, an omission where a legal duty exists, or a prohibited state of affairs. It excludes the defendant's mental state.

The mental element of an offence: the state of mind the prosecution must prove, such as intention, knowledge, recklessness, or negligence, depending on how the offence is defined.

A bodily movement performed under the person's conscious control. Only voluntary conduct can ordinarily ground criminal liability; reflexes and movements during unconsciousness generally do not.

A failure to act. It is criminal only where the law imposes a duty to act, such as under statute, contract, a special relationship, or where the defendant created the danger.

A legally recognized obligation that turns inaction into a punishable omission, arising from statute, relationship, assumption of care, contractual duty, or creation of a risk.

The link between the defendant's conduct and the prohibited result. It requires factual cause (but-for cause) and legal or proximate cause, which asks whether the result was a foreseeable consequence.

The factual test of causation: the result would not have occurred when it did but for the defendant's conduct. It is necessary but not sufficient for liability.

The legal limit on causation. Conduct is a proximate cause if the result was a reasonably foreseeable consequence and no sufficiently independent intervening event broke the chain.

A new intervening act or event that breaks the chain of causation, so the original actor is not liable for the later result. It must be independent and not reasonably foreseeable.

The highest level of culpability: the defendant aims at or desires the prohibited result, or foresees it as virtually certain and acts anyway (oblique intention).

Consciously taking an unjustified risk that a prohibited circumstance exists or a result will occur. Subjective recklessness requires awareness of the risk; objective recklessness uses a reasonable-person standard.

A failure to exercise the care a reasonable person would exercise in the circumstances. Criminal negligence usually requires a gross departure from the standard of care.

A term of art in many offence definitions meaning either an actual intention to cause the harm or recklessness as to whether that harm occurs. It does not necessarily mean hatred or ill will.

Liability imposed without proof of mens rea as to at least one element of the offence, typically a regulatory or public-welfare offence. Defences of mistake are usually limited.

A doctrine that shifts the defendant's guilty intent from the intended victim or object to the actual victim or object harmed, allowing conviction for the completed offence.

A complete defence where the defendant acted involuntarily due to an external cause, such as a blow or medication, and was not conscious of what they were doing.

A defence based on a mental disorder that deprived the defendant of the capacity to understand the nature of the act or to know it was wrong, applying the governing legal test.

A partial defence in some jurisdictions that reduces murder to manslaughter where a recognized mental abnormality substantially impaired the defendant's mental responsibility.

A defence or mitigating factor where the defendant's voluntary or involuntary consumption of substances negated the mens rea required for the offence.

An offence requiring proof that the defendant intended a particular result or further act beyond the basic act, such as burglary with intent to commit a felony inside.

An offence requiring only that the defendant intended to perform the prohibited act, without proof of intent to achieve a further consequence.

An inchoate offence committed when the defendant, with the required intent, takes a substantial step beyond mere preparation toward completing the target crime.

The conduct threshold for attempt in many jurisdictions: an act strongly corroborative of the defendant's criminal purpose, going beyond remote preparation.

Arranging means or planning before a crime. Mere preparation is generally not punishable as an attempt unless it crosses into a substantial step.

An agreement between two or more people to commit an unlawful act, often accompanied by an overt act in furtherance. The agreement itself is the offence.

Inciting, requesting, or commanding another person to commit a crime, with the intent that the crime be committed. It is complete upon the request.

Liability of a person who aids, abets, counsels, or procures the commission of an offence, with the intent to assist, for the crime committed by the principal.

The person who actually commits the actus reus of the offence, or who uses an innocent agent to do so, and is liable as the main offender.

A person who, knowing an offence has been committed, assists the offender to escape arrest or punishment. Liability is separate and usually lesser.

A joint criminal enterprise doctrine: participants who share a common purpose are each liable for crimes committed in furtherance of that purpose, subject to foreseeability limits.

A justification allowing reasonable force to protect oneself from an imminent unlawful attack. The force used must be necessary and proportionate to the threat.

A justification permitting reasonable force to protect another person from an imminent unlawful attack, judged on the circumstances as the defender reasonably believed them.

A defence of justification where the defendant commits an offence to avoid a greater harm, with no reasonable alternative and no situation created by the defendant's own fault.

An excuse where the defendant commits an offence because of a threat of death or serious harm that a person of reasonable firmness could not resist.

A partial defence reducing murder to manslaughter where the victim's conduct caused the defendant to lose self-control, judged by both subjective and objective standards.

A defence where the defendant's honest (and sometimes reasonable) mistake negates the mens rea of the offence or supports a justification belief.

The dishonest appropriation of property belonging to another with the intention of permanently depriving the owner of it.

Theft accomplished by the use or threat of force against a person, immediately before or at the time of taking, in order to steal.

Entering a building or dwelling as a trespasser with intent to commit theft, grievous bodily harm, or another specified offence, or committing such an offence after entry.

An act causing another person to apprehend immediate unlawful personal violence, or the actual application of unlawful force, depending on the statutory definition.