The central question of legal euthanasia is whether any form of euthanasia is morally permissible. Many defenders of euthanasia justify their positions by appealing to the values of liberty, autonomy, and self-determination. They argue that rational, competent adults should have the right to make responsible decisions regarding their own lives, provided they respect others' right to self-determination. Respecting one's right to self-determination includes allowing him or her to commit euthanasia. Legal prohibitions on euthanasia then constitute unwarranted government intervention in an exercise of autonomy. Others may also argue similarly that making voluntary active euthanasia available to the terminally ill allows them a measure of dignity in the face of the final and ravaging stages of their illnesses. They support those committed to the value of mercy that would in certain cases agree to assist terminally ill persons in their efforts to end their lives. To refuse to accede to the requests of a terminally ill person suffering unbearable pain would be cruel, callous, and heartless.

Some opponents of euthanasia find it morally objectable because it involves someone forming and acting on a direct intention to bring about a human person's death. They argue that it is morally impermissible to directly intend to terminate the life of a human person no matter the circumstances. Their concerns are instead based on fear of undesirable consequences that might result, should society make euthanasia widely available. They worry that if society should sanction physician assisted suicide, then inevitably abuses would occur, which would disproportionately affect the most vulnerable members of society. They bring up questions like: If society were to permit physician-assisted suicide, what might be its effect on physicians and other health care professionals? Might not this erode patients' trust in physicians and nurses?

It might be argued that euthanasia would erode the physician's duty to keep his or her creditable relationship with their patients, however this ignores the duty of medical mercy that a physician has. It is only by virtue of their more frequent exposure to pain and their specialized training in its treatment that this duty falls more heavily on physicians. Physicians have two major duties, which pertain to mercy. First, they have the duty not to cause further pain or suffering. And secondly, they have the duty to act to end pain or suffering already occurring. These duties would then make it permissible for a physician to perform euthanasia. However, this must never override the respect to a competent person's choices, where doing so will not violate other moral obligations or harm other persons. There must be a necessary protection against the abuse that may occur, without having to eliminate it. Physicians must be given their authority to perform euthanasia, while being held accountable for their exercise of that authority. Physicians, whose training and professional norms give some assurance that they would perform euthanasia responsibly, are an appropriate group of persons to whom the practice may be restricted.