I return to the patient who because for example he is

I return to the patient who, because for example he is of unsound mind or has been
rendered unconscious by accident or by illness, is incapable of stating whether or not
he consents to treatment or care. In such circumstances, it is now established that a
doctor may lawfully treat such a patient if he acts in his best interests, and indeed that,
if the patient is already in his care, he is under a duty so to treat him: see In re F.
(Mental Patient: Sterilisation) [1990] 2 A.C. 1, in which the legal principles governing
treatment in such circumstances were stated by this House. For my part I can see no
reason why, as a matter of principle, a decision by a doctor whether or not to initiate,
or to continue to provide, treatment or care which could or might have the effect of
prolonging such a patient's life, should not be governed by the same fundamental
principle. Of course, in the great majority of cases, the best interests of the patient are
likely to require that treatment of this kind, if available, should be given to a patient.
But this may not always be so. To take a simple example given by Thomas J. in
Auckland Area Health Board v. Attorney-General [1993] 1 N.Z.L.R. 235, 253, to whose
judgment in that case I wish to pay tribute, it cannot be right that a doctor, who has
under his care a patient suffering painfully from terminal cancer, should be under an
absolute obligation to perform upon him major surgery to abate another condition
which, if unabated, would or might shorten his life still further. The doctor who is caring
for such a patient cannot, in my opinion, be under an absolute obligation to prolong his
life by any means available to him, regardless of the quality of the patient's life.
Common humanity requires otherwise, as do medical ethics and good medical practice
accepted in this country and overseas. As I see it, the doctor's decision whether or not
to take any such step must (subject to his patient's ability to give or withhold his
consent) be made in the best interests of the patient. It is this principle too which, in
my opinion, underlies the established rule that a doctor may, when caring for a patient
who is, for example, dying of cancer, lawfully administer painkilling drugs despite the
fact that he knows that an incidental effect of that application will be to abbreviate the
patient's life. Such a decision may properly be made as part of the care of the living
patient, in his best interests; and, on this basis, the treatment will be lawful. Moreover,
where the doctor's treatment of his patient is lawful, the patient's death will be
regarded in law as exclusively caused by the injury or disease to which his condition is
attributable.
It is of course the development of modern medical technology, and in particular the

CRIMINAL LAW 2019-20
LLB CASEBOOK: PART 1 – TOPIC 3
164
development of life support systems, which has rendered cases such as the present so
much more relevant than in the past. Even so, where (for example) a patient is brought