Novus Actus Interveniens
A new intervening act that breaks the chain of causation between the defendant's breach and the claimant's damage. May be the act of a third party, the claimant, or a natural event.
Independent editorial summary — not the official statute text. Read the official version on legislation.gov.uk.
For a defendant to be held responsible for a death or injury, their act must remain a legally operative cause of the outcome at the time it occurs. The Crown Prosecution Service's guidance on causation in homicide cases puts the underlying test simply: the suspect's act must be a substantial cause of the death, though it need not be the only or main one.
An intervening event — a novus actus interveniens — can break that chain where it becomes the true cause of the outcome instead. Even so, the chain is not automatically broken by every subsequent event: CPS guidance notes, for example, that a victim's own suicide following a defendant's unlawful act will not necessarily break the chain of causation, provided the injury the defendant caused remained an operating and significant cause of death.
Related terms
Official sources
This explanation is drawn from the official sources below; every substantive statement is verified against them. For advice on a specific matter, see our find help page.