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Can suicide break the chain of causation?

The principles of "causation" have been examined  in a recent trial at Bristol Crown Court last month. In this case, the prosecution have sought to argue that the act of the defendant throwing sulphuric acid over the victim, which resulted in catastrophic but not fatal injuries, constituted murder. The injuries sustained by the victim included paralysis from the neck down and meant that he would require round-the-clock care for the rest of his life. The victim subsequently underwent elective euthanasia at a clinic in Switzerland. A further complication in this case is the illegality in this jurisdiction of the act of suicide. This trial was adjourned at the end of November 2017 by Mrs Justice May to allow a question of law to be considered. The jury have been discharged and a provisional trial date has been set of April 2018.

Questions of causation can be difficult.  There are two types of causation: factual causation and legal causation.  To establish factual causation, it must be said that but for the defendant’s actions, the result would not have occurred. Authority for this proposition stems from the case of R v White [1910] 2 KB 124 where a son placed cyanide in his mother’s drink intending to kill her and later that night she died. Medical evidence held that the mother had died from a heart attack before the cyanide could take effect. As such, factual causation could not be established because but for the son’s actions, the mother would still have died.

In a simple case where A shoots B and B subsequently dies from the injuries, factual causation is apparent and one need go no further - but for A shooting B, B would not have died. The scenario becomes more complex in a case involving an intervening act (or novus actus interveniens) and this is where legal causation comes into play. To establish legal causation, it must be shown that the defendant’s act was an ‘operative and substantial’ cause. In other words there cannot be an ‘intervening act’ breaking the chain of causation.  If A shoots B in the leg and then in an unconnected incident B is fatally shot in the head by C, A cannot be liable for the murder of B because the wound to B’s leg was not the operative and substantial cause of his death. B had died as a result of the subsequent, unconnected act of C shooting him. This example deals with the intervening act of a third party, however the same principles are also applicable in cases involving acts committed by the victim themselves.

In the case of R v Blaue [1975] 61 Cr App R 271, the victim was stabbed by the defendant several times and required a blood transfusion to survive. Due to her religious beliefs, the victim refused the blood transfusion and died. The Court of Appeal held that the defendant had to ‘take the victim as he found her’ and could not argue that her death had been caused by her own actions.  In the case of

R v Malcherek [1981] 2 All ER 422 the defendant stabbed his wife multiple times and she was taken to hospital where she was placed on life support, having suffered severe brain damage. The doctors’ made the decision to switch off her life support machine and the defendant argued that the doctors’ decision constituted a novus actus interveniens and subsequently broke the chain of causation. The Court of Appeal dismissed this argument and held that the operating and substantial cause of the victim’s death had been the original wounds inflicted by the defendant.

Similarly, in the case of R v Dear [1996] Crim LR 595 the defendant had slashed the victim several times with a Stanley knife and she had died shortly after. The defendant sought to argue that the victim had committed suicide by attempting to re-open the wounds and as such her actions had constituted a novus actus interveniens, breaking the chain of causation. This line of argument was dismissed by the Court of Appeal who reiterated that the real question was whether the injuries inflicted by the defendant constituted an operating and substantial cause of the death.

Brett Wilson LLP solicitors are experienced in advising and representing those under investigation or being prosecuted for criminal offences. Click here to see how we can assist you.


Legal Disclaimer

Articles are intended as an introduction to the topic and do not constitute legal advice.