Causation refers to inquiry as to whether the defendants conduct (or omission) caused the harm or damage. Causation must be established in all result crimes. In criminal liability it is divided into Factual causation and Legal causation. Factual causation is the starting point and consist of applying the ‘but for’ test. In most instances where there exists no complicating factors, factual causation on its own will suffice to establish causation. However, in some circumstances it will also be necessary to consider Legal causation. Under legal causation the result must be caused by a culpable act. There is no requirement that the act of the defendant was the only cause, there must be no Novus Actus Interviens (new intervening act) and the defendant must take his victim as he finds him.
Factual causation is established by applying the ‘but for’ test. This asks, keepin aside D’s conduct, would the consequences have come about? If YES, the result would have occurred in any event thus the defendant is not liable. If the answer is NO. the defendant is liable as it can be said that there action was the factual cause of the result. This can be seen in the case of R v White where the defendant, son mixed poison in his mother’s drink with intention of killing her. She took some sips and slept but never woke up. The postmortem report revealed that she died of a heart attack not poison. The defendant was not liable for her murder as his act of poisoning was not the cause of death. He was liable for attempt.
Legal causation requires that the harm must result from a culpable ct. To be a legal cause, the defendant’s contribution to the result must be substantial, although it need not be the sole cause. It is also necessary to ask that to what extent defendant act significantly contributed to the result. In Adams (1957) a doctor gave his terminally ill patient a dose of painkillers so strong that it killed the patient. Doctor was acquitted of murder his contribution