## Facts

- The defendant (D) assaulted his former partner (V) by pouring acid onto V’s face, causing severe permanent injuries and psychological distress.
- As a result of these injuries, V travelled to Belgium where he encountered further medical issues and chose to undergo legally sanctioned euthanasia administered by a doctor.
- D was prosecuted for murder and other offences following V’s death via euthanasia.
- D’s counsel argued that the lawful euthanasia constituted a _novus actus interveniens_ (new intervening act) that broke the causal chain, thus negating liability for murder.
- The Crown Court accepted this argument and withdrew the murder charge from the jury.
- The prosecution appealed the decision.

## Issues

1. Whether the victim’s act of seeking and undergoing euthanasia constituted a _novus actus interveniens_ that broke the chain of causation between the defendant’s actions and the victim’s death.
2. Whether the acts of the victim and Belgian doctor were truly independent and voluntary so as to sever the defendant’s legal responsibility.
3. What standard should be applied in evaluating causation: whether the defendant’s act must be a ‘substantial’ or ‘significant’ contributing factor to the result.
4. How established principles from previous authorities, such as _Dear_, should inform the determination of causation in cases involving victim-initiated acts resulting in death.

## Decision

- The Court of Appeal held that the acts of seeking and administering euthanasia were not independent, genuinely voluntary acts sufficient to break the chain of causation.
- It determined that the victim’s request for euthanasia and the doctor’s conduct were direct responses to the defendant’s original assault, not acts of ‘free and unfettered volition’.
- The Court rejected a strict philosophical approach to causation, emphasizing a common sense evaluation under the circumstances.
- It clarified that an intervening act will only break causation if it is independent and not a reasonably foreseeable consequence of the original conduct.
- The Court replaced the requirement that the defendant’s acts be a ‘substantial’ cause of death with the requirement that they be a ‘significant’ factor.
- The Court relied on the decision in _Dear_ to support liability where the victim’s response, even if fatal, resulted from the injuries inflicted by the defendant.
- The appeal was allowed, setting aside the earlier decision to withdraw the murder charge from the jury.

## Legal Principles

- The chain of causation remains intact unless an intervening act is truly independent, voluntary, and not a foreseeable consequence of the defendant’s original conduct.
- For an act to be a _novus actus interveniens_, it must result from ‘free and unfettered volition’.
- The definition of legal causation is clarified: the defendant’s act need only be a ‘significant’ contributing factor, not necessarily the predominant or sole cause.
- The approach to causation should apply common sense to all the circumstances rather than rely on abstract, philosophical distinctions.
- The precedent established in _Dear_ confirms that a victim’s action following severe injury does not automatically exclude liability if that action is a direct response to the harm caused.

## Conclusion

The Court of Appeal in R v Wallace [2018] EWCA Crim 690 clarified the law of causation in criminal offences, holding that a victim’s actions do not break the chain of causation if they are direct, foreseeable responses to the defendant’s conduct and affirming that legal responsibility attaches where the original act is a significant factor contributing to the outcome.
