The United Kingdom, in common with many countries, faces a shortage of donor organs for transplantation.1 One of the obstacles to increased donation is the widespread view within the medical profession that it is unlawful to alter the management of a patient who is dying solely to improve or maintain the prospect of that patient becoming an organ donor after death.2 Such concerns are particularly relevant to controlled non-heart-beating organ donation, where organs are taken from patients who have a cardiorespiratory death after the planned withdrawal of active support in intensive care units.3 Although this was the original model of cadaveric donation in the UK, it has proved contentious since its re-emergence as an important source of donor organs in recent years.4 We explore how the concept of best interests should be understood, and thereby show that apparent ethicolegal objections to controlled non-heart-beating organ donation by patients who are unable to provide informed consent are illusory.

If there comes a stage where the responsible doctor comes to the reasonable conclusion (which accords with the views of a responsible body of medical opinion) that further continuance of an intrusive life support system is not in the best interests of the patient, he can no longer lawfully continue that life support system: to do so would constitute the crime of battery and the tort of trespass to the person.8

The answer to the question [of whether withdrawal of care is in the patient’s best interests] must of course depend on the circumstances of each case and there will be no single “right” answer. Different doctors may take different views both on strictly medical …