Once legalized, physician-assisted suicide and euthanasia would become routine. Over time doctors would become comfortable giving injections to end life and Americans would become comfortable having euthanasia as an option. Comfort would make us want to extend the option to others who, in society's view, are suffering and leading purposeless lives. The ethical arguments for physician-assisted suicide and euthanasia, advocates of euthanasia have maintained, do not apply to euthanasia only when it is voluntary; they can also be used to justify some kinds of nonvoluntary euthanasia of the incompetent. Euthanasia would come to be seen as "one end of a spectrum of caring for dying patients," as the philosopher and euthanasia defender Dan Brock writes. "When viewed in this way," he goes on, "it will be difficult to deny euthanasia to a patient for whom it is seen as the best or most appropriate form of care simply because that patient is now incompetent and cannot request it."

Advocates of physician-assisted suicide and euthanasia urge legalization for reasons of compassion, but there is no guarantee that the reasons offered in 1997 would remain the justification even a few years ahead, under different social and economic circumstances. The confluence of ethical arguments, medical practice, demographic and budgetary pressures, and a social ethos that views the old and sick as burdens would seem capable of overwhelming any barriers against euthanasia for incompetent patients.

The proper policy, in my view, should be to affirm the status of physician-assisted suicide and euthanasia as illegal. In so doing we would affirm that as a society we condemn ending a patient's life and do not consider that to have one's life ended by a doctor is a right. This does not mean we deny that in exceptional cases interventions are appropriate, as acts of desperation when all other elements of treatment—all medications, surgical procedures, psychotherapy, spiritual care, and so on—have been tried. Physician-assisted suicide and euthanasia should not be performed simply because a patient is depressed, tired of life, worried about being a burden, or worried about being dependent. All these may be signs that not every effort has yet been made.

By establishing a social policy that keeps physician-assisted suicide and euthanasia illegal but recognizes exceptions, we would adopt the correct moral view: the onus of proving that everything had been tried and that the motivation and rationale were convincing would rest on those who wanted to end a life. Such a policy would recognize that ending a life by physician-assisted suicide or euthanasia is an extraordinary and grave event. To recognize a legal right to physician-assisted suicide or euthanasia transforms the practices into routine interventions that can be administered without the need for a publicly acceptable justification. Doctors who end patients' lives would no longer bear the burden of having to prove the appropriateness of their action, if called upon to do so, but could simply justify their action as a legally sanctioned procedure.

Advocates for legalization might find a policy that permits exceptions to embody a double standard. But crafting a social policy in this way would also embody what we know: not all cases are the same, and among the millions of Americans who die each year there are morally relevant differences that cannot be captured in an inflexible rule. We must ensure that moral judgments are made in individual cases, and that those who make them will be accountable before the law.