R v White  2 KB 124
CAUSATION - ATTEMPT
The defendant put poison into the evening drink of the victim, his mother, with the intention of killing her. The victim drank a few sips of the drink and then fell asleep. She did not wake up, however the medical evidence was that she had died of a heart attack rather than as a result of the poison. The defendant also gave evidence that he had not intended to kill her by a single dose but had planned to deliver multiple doses over a longer period of time. The defendant was convicted of attempted murder.
On appeal, the question arose as to whether the defendant could be liable for murder given that his actions had not factually caused the death. A second issue was whether having delivered a single dose was a sufficient ‘attempt’ to ground the conviction in light of the evidence that the defendant had intended the victim to die as a result of later doses which were never administered.
The court established the ‘but for’ test of causation, according to which the defendant could not be convicted unless it could be shown that ‘but for’ his actions the victim would not have died. On the facts of this case the test was not met, therefore the defendant could not be convicted of murder.
On the issue of attempt, the court held that it was sufficient that the attempted murder had been begun, notwithstanding that the defendant had not completed his plan. The conviction for attempted murder was therefore upheld.