This article addresses the question of whether the defence of necessity could be utilised in cases of euthanasia in the medical context. It challenges the application of the doctrine of double effect as a means of ascertaining the physician's primary intent and argues instead that the law should recognise that the physician faces a situation of necessity. It asserts that given the potential availability of the defence of diminished responsibility to a relative or spouse who carries out a mercy killing, not allowing the physician to utilise the defence of necessity may place him at greater risk of conviction for murder than the layperson.