While opinion polls show that a majority of Americans approve of physician-assisted suicide and want it to be legalized, most doctors say they would not assist a person to prematurely end his or her life. Influenced by the prevailing code of medical ethics, many physicians maintain that it is wrong to hasten the death of terminally ill patients. But a growing number argue that if it will prevent undue suffering, assisting patients who rationally choose to commit suicide is acceptable.

Among those seeking to legalize assisted suicide is Timothy E. Quill, a physician in Rochester, New York, whose 1993 book Death and Dignity: Making Choices and Taking Charge describes his decision to help a patient dying from leukemia end her life. Under current standards of medical ethics, Quill notes, terminally ill patients may refuse life-prolonging treatment and doctors may legally withdraw...