Week 5 tutorial: Actus reus – causation
When assessing liability for a result crime such as homicide offences, criminal damage, etc a result
element must be found. Essential to demonstrate a causal link betweens D’s conduct element and
that result.
If D’s conduct element (movement or omission) did not cause the result element there will be no
liability for a result crime.
The application of the causation rules:
• Causation in fact: Did the result come about because of D’s conduct?
• Causation in law: Was D’s conduct a substantial; blameworthy; and operating cause?
Causation in fact
Factual causation is generally asking whether the result came about because of D’s contributory
act or her failure (omission) to prevent the result. The ‘but for test’: it must be proved that, but for
D’s conduct element, the result would not have come about.
If D’s conduct is not a factual cause there can be no causation. R v White.
• Accelerating the result: As long as D’s conduct caused the result to come about when it did, he
is the factual cause. It is irrelevant if it would have come about later without D’s involvement.
• More than one cause: As long as the result would not have happened but for D’s conduct, it is
not necessary to show that D was the only cause. R v Benge.
Causation in law
The basic test for factual causation must be supplemented with a test for legal causation to avoid
an overly broad catchment.
Legal cause must be ‘substantial’
D’s conduct element must have made a substantial contribution to the result, although he doesn’t
have to be the main cause. As long as D’s role is not de minimis it will satisfy this requirement: D’s
role must be more than ‘slight or trifling’, ‘negligible’, or ‘insubstantial or insignificant’.
The fact that D’s conduct element is a factual cause will not automatically satisfy this requirement.
Legal cause must be ‘blameworthy’
When a result crime is created, it is usually attempting to target certain wrongful or blameworthy
conduct that leads to a harmful result. It is essential to identify the conduct that caused the result
and then ask if that conduct was the blameworthy conduct that is the target of the criminal law.
R v Dalloway. ( his conduct was blameworthy but was not the cause of the death)
R v Hughes. ( it must be shown that the blameworthy conduct caused the death, not simply that
they both occurred).
Legal cause must be ‘operative’
The term operative means that D’s conduct must still be a significant cause of the result at the time
it comes about. The chain of causation between conduct and result elements must not be broken.
The causation chain can break as a result of the subsequent actions of D, natural events, the
actions of V, or the actions/omissions of a third party.
Intervention from D
D having wounded V, visits her in hospital and accidentally infects her with smallpox which she
dies. Here, D’s original conduct (wounding) is superseded by the primary cause of death
(infections) D remains liable for a wounding offence, but that initial conduct is not the legal cause of
of the death.
Intervention from naturally occurring events
These events will only break the chain of causation if they are unforeseen by D and unforeseeable
to the reasonable person. Where D attacks V and then leaves her in a safe environment, only for V
When assessing liability for a result crime such as homicide offences, criminal damage, etc a result
element must be found. Essential to demonstrate a causal link betweens D’s conduct element and
that result.
If D’s conduct element (movement or omission) did not cause the result element there will be no
liability for a result crime.
The application of the causation rules:
• Causation in fact: Did the result come about because of D’s conduct?
• Causation in law: Was D’s conduct a substantial; blameworthy; and operating cause?
Causation in fact
Factual causation is generally asking whether the result came about because of D’s contributory
act or her failure (omission) to prevent the result. The ‘but for test’: it must be proved that, but for
D’s conduct element, the result would not have come about.
If D’s conduct is not a factual cause there can be no causation. R v White.
• Accelerating the result: As long as D’s conduct caused the result to come about when it did, he
is the factual cause. It is irrelevant if it would have come about later without D’s involvement.
• More than one cause: As long as the result would not have happened but for D’s conduct, it is
not necessary to show that D was the only cause. R v Benge.
Causation in law
The basic test for factual causation must be supplemented with a test for legal causation to avoid
an overly broad catchment.
Legal cause must be ‘substantial’
D’s conduct element must have made a substantial contribution to the result, although he doesn’t
have to be the main cause. As long as D’s role is not de minimis it will satisfy this requirement: D’s
role must be more than ‘slight or trifling’, ‘negligible’, or ‘insubstantial or insignificant’.
The fact that D’s conduct element is a factual cause will not automatically satisfy this requirement.
Legal cause must be ‘blameworthy’
When a result crime is created, it is usually attempting to target certain wrongful or blameworthy
conduct that leads to a harmful result. It is essential to identify the conduct that caused the result
and then ask if that conduct was the blameworthy conduct that is the target of the criminal law.
R v Dalloway. ( his conduct was blameworthy but was not the cause of the death)
R v Hughes. ( it must be shown that the blameworthy conduct caused the death, not simply that
they both occurred).
Legal cause must be ‘operative’
The term operative means that D’s conduct must still be a significant cause of the result at the time
it comes about. The chain of causation between conduct and result elements must not be broken.
The causation chain can break as a result of the subsequent actions of D, natural events, the
actions of V, or the actions/omissions of a third party.
Intervention from D
D having wounded V, visits her in hospital and accidentally infects her with smallpox which she
dies. Here, D’s original conduct (wounding) is superseded by the primary cause of death
(infections) D remains liable for a wounding offence, but that initial conduct is not the legal cause of
of the death.
Intervention from naturally occurring events
These events will only break the chain of causation if they are unforeseen by D and unforeseeable
to the reasonable person. Where D attacks V and then leaves her in a safe environment, only for V
