Ratio Decidendi
The 'but for' test of factual causation: the defendant's act must be a factual cause of the prohibited result. If the victim would have died the same way regardless, causation is not established.
Facts
White put potassium cyanide in his mother's drink intending to kill her. She was found dead but medical evidence showed she died of heart failure, not poisoning.
Judgment Summary
White was acquitted of murder but convicted of attempted murder. The poison did not cause death — the 'but for' test was not satisfied.
Key Quotes
"The prisoner clearly intended to murder his mother by administering poison. But the medical evidence shows that she did not die from poison but from heart failure."
— The Court
Subsequent Treatment
Good law
Standard illustration of the 'but for' test of causation in criminal law.