To this point my focus has largely been on the permissibility of competent dying patients choosing the manner and timing of their death, including, where necessary, with medical assistance. However, it is a fact of life for many patients that by the time death looms they are no longer competent and so are unable to make autonomous decisions. For these dying patients, it is, therefore, of great significance whether reliance can be placed on end-of-life choices made while they were competent. In particular, it is of great significance whether careful, written specifications of those choices (in the form of advance directives, or what are sometimes called ‘living wills’) should be accorded a privileged status as conveying competently formed convictions that are to bind their end-of-life treatment.

To decide these matters it will be necessary to consider whether the ‘prior consent’ recorded in an advance directive can be considered authentic given the impossibility of confirming or ratifying it once competence is lost. (When a patient remains competent, and so is able to confirm the instructions in his advance directive, this issue will not arise. No competent individual can be bound by what he earlier decided, so a competent individual can simply overturn an advance directive if he undergoes a change of mind. Not to allow him to change his mind would itself be a serious infringement of his autonomy.)