It is never lawful or ethical to withdraw life-sustaining treatment from patients with prolonged disorders of consciousness.

In English law there is a strong (though rebuttable) presumption that life should be maintained. This article contends that this presumption means that it is always unlawful to withdraw life-sustaining treatment from patients in permanent vegetative state (PVS) and minimally conscious state (MCS), and that the reasons for this being the correct legal analysis mean also that such withdrawal will always be ethically unacceptable. There are two reasons for this conclusion. First, the medical uncertainties inherent in the definition and diagnosis of PVS/MCS are such that, as a matter of medical fact, it can never be established, with the degree of certainty necessary to rebut the presumption, that it is not in the patient's best interest to remain alive. And second (and more controversially and repercussively), that even if permanent unconsciousness can be unequivocally demonstrated, the presumption is not rebutted. This is because there is plainly more to human existence than consciousness (or consciousness the markers of which can ever be demonstrated by medical investigations). It can never be said that the identity of the patient whose best interests are at stake evaporates (so eliminating the legal or ethical subject) when that person ceases to be conscious. Nor can it be said that the best interests of an unconscious person do not mandate continued biological existence. We simply cannot know. That uncertainty is legally conclusive, and (subject to resource allocation questions and views about the relevance of family wishes and the previously expressed wishes of the patient) should be ethically conclusive.