R v Miller  2 AC 161
ACTUS REUS - DUTY OF CARE - OMISSION
The defendant was a vagrant who had spent the evening drinking before returning to the property where he was squatting. He fell asleep with a lit cigarette in his hand, which started a fire. The defendant woke and, seeing the fire, took no steps to extinguish it but simply moved to sleep in a different room. Eventually the whole house caught fire, causing over £800 worth of damage. The defendant was charged with arson.
Because the prosecution relied on the ground that the defendant had failed to take any action to extinguish the fire in addition to the fact that he had been reckless in starting the fire by falling asleep with a lit cigarette, the question arose whether the defendant could be liable for an omission. If it was not, then the actus reus of arson was not present and no conviction for arson would be possible.
The court concluded that as he was responsible for having created the dangerous situation, the defendant was under a duty to take action to resolve it once he became aware of the fire. It was not necessary that the defendant was subjectively aware of the risk of damage posed by the fire, provided that this would be obvious to a reasonable person who troubled to turn his mind to the matter. The defendant was therefore liable for his omission to take any steps to put out the fire or seek held, and was accordingly convicted of arson.