Compare the following two cases:

Poison: Patient is terminally ill and is in a lot of pain that cannot be relieved through palliative measures. In order to bring his suffering to an end, Doctor injects Patient with some poison and Patient dies.

Dehydration: Patient is terminally ill and is in a lot of pain that cannot be relieved through palliative measures. Doctor orders that Patient should not be given any more food and water, and Patient dies of dehydration.

In Poison, Doctor commits murder. In Dehydration, Doctor does not commit any crime at all. But the only difference between these two cases is that Doctor has performed an act in Poison whereas all he is guilty of in Dehydration is an omission. Doctor could only be held liable for his omission in Dehydration if he had a duty to continue feeding Patient and giving him water; but he would have had no such duty if there was no point in continuing to treat Patient and giving Patient food and water is regarded as part of Patient’s ‘treatment’ (as it was in Airedale NHS Trust v Bland). In contrast, Doctor will always be under a duty not to take positive steps to bring Patient’s life to an end.

But we can’t just rest content with saying that Doctor is held liable in Poison while he is held blameless in Deyhydration because he breached a duty in Poison while he did not in Dehydration. That just raises the question of why there is a duty not to act in Poison when there is no duty to act in Dehydration. Why is what Doctor did in Poison so much worse than what he failed to do in Dehydration that the law will say that there was a duty not to act in Poison while there was no duty to act in Dehydration? After all, if we are just looking at the consequences of what Doctor did, Doctor’s actions in Poison look a lot better than Doctor’s omissions in Dehydration. In Poison, Doctor brought Patient’s suffering to a quick and painless end. In Dehydration, Doctor condemned Patient to a very difficult, agonising and prolonged death (though doing so may still have been in Patient’s ‘best interests’ given the alternative of allowing Patient to continue to suffer weeks or even months of extreme pain before the final end).

Some would argue, on this basis, that (to quote Lord Mustill in Bland) the law is ‘both morally and intellectually misshapen’ in distinguishing between Poison and Dehydration and that we should not find Doctor guilty of murder in Poison. Others (see, for example, Finnis, ‘Bland: crossing the Rubicon?’ (1993) 109 LQR 329) would agree with the premise of this argument but disagree with the conclusion: they would argue that we can only restore order to this area of the law by overruling Bland and holding that Doctor is just as much guilty of murder in Dehydration as he is in Poison: giving a patient food and water should not be regarded as being part of a patient’s ‘medical treatment’ and even if there is no further point in giving the patient medical treatment, there is still a duty to give the patient food and water so long as the patient is able to ingest it. So a breach of that duty that brings about death, when accompanied with an intent to kill, should be regarded as murder.

From a religious point of view, it is easy to see why we might distinguish between Poison and Dehydration. In Poison, Doctor is intervening to alter the natural course of events that would otherwise determine when Patient dies – which is not allowed if you think that that natural course of events represents God’s will for when Patient should die. In contrast, in Dehydration, Patient dies of natural causes – if you don’t get water for long enough, you die. And while we could argue about whether Doctor violated God’s will in withholding food and water from Patient – with the result that, from a religious perspective, his failure to act in Dehydration is just as bad as his act in Poison – the fact that Poison represents a much more obvious case of ‘playing God’ than Dehydration may be enough to justify our drawing a distinction between the two cases.

However, in a secular society, religious arguments for distinguishing between Poison and Dehydration are out of bounds. Can we find a non-religious basis for distinguishing between these two cases? The normal secular arguments for why the law should draw distinctions between acts and omissions – that if the law is too ready to find duties to act this will (1) undermine civil liberties; (2) create a great deal of uncertainty in the law; (3) deprive people of opportunities to earn credit from others for doing the right thing when they weren’t compelled to do so; (4) ‘punish’ people for putting themselves in positions to help others in need by subjecting them to legal duties that people who have made more selfish choices will never incur – don’t seem to apply here to distinguish Poison from Dehydration. If the law said there were a duty to act in Dehydration, doing so wouldn’t seem to have any of the undesirable effects that would normally accompany the law’s finding that one stranger owed another stranger a duty to save him or her from harm. However, it may be that we can make a ‘civil liberties’ argument in favour of the law’s finding that Doctor had a duty not to act in Poison when it says that he did not have a duty to act in Dehydration.

The argument goes as follows: if the law finds that it was permissible for Doctor to kill Patient in Poison, then it will not be long before the law finds that it was compulsory for Doctor to kill Patient in Poison. This is because the law gives doctors very little leeway in treating their patients – either the doctor had a duty to administer a particular treatment, or he had a duty not to administer that treatment: the law rarely (never?) says to a doctor ‘It’s entirely up to you whether or not to you administer that treatment.’ So if the law said it was permissible for Doctor to kill Patient in Poison then it’s hard to see how it could not then make the further leap of saying that it was compulsory for Doctor to kill Patient in Poison. But saying this would involve a very serious interference with Doctor’s civil liberties: many doctors do not want (for whatever reason) to kill their patients, and would seriously resent the law’s compelling them to kill their patients. And if doctoring were seen as coming with a duty to kill in certain circumstances, then the number of people wanting to become doctors would radically diminish. The same problem does not arise in relation to the law’s saying that Doctor has no duty to feed or water Patient in Dehydration. If the law follows that up by saying that it is compulsory for Doctor not to give Patient any food or water in Dehydration, most doctors would be able to be reconciled with that. The fact that the law might get in the way of a doctor acting on her normal instinct to give a patient food or water – even if nothing more can be done for the patient – would not be experienced by the doctor as a violation of her civil liberties any more than the fact that the size or location of her hospital places a limit on how many patients she can treat, or her need to respect her patient’s wishes places a limit on what she can do for that patient. The state of the law would just be one more fact which places a limit on how much she can do for the patients she would otherwise wish to treat, and which she just has to learn to live with.