The sharp contrast between the vast number of detailed statutory provisions defining particular offences and the small handful of widely phrased provisions concerned with the general principles of criminal liability is, perhaps, the most striking feature of English criminal law, and, like the continued co-existence of both common law and statutory offences, one of the unhappy consequences of England's failure to enact a penal code. Among the few statutory provisions laying down general principles of liability or excuse there is none which comprehends a defence of necessity, and so commentators have inevitably looked to the case law for an answer to the question: Is there in English criminal law a defence of necessity? by which they have meant: Is there a defence of necessity in the sense in which there is a defence of, for instance, insanity, or infancy, or duress or prevention of crime? To the question understood in that sense, the answer returned must, it is thought, be a plain No. To ask and to answer the question in that sense may, however, be misleading: it may be more revealing (as this paper suggests) to ask, How does English law handle the plea of necessity when it arises? What, in other words, is the juristic technique employed?