From the Practical Ethics blog:

Sir Terry Pratchett’s documentary, “Choosing to die” and the recent deaths of Ann McPherson and Jack Kevorkian (inventor of the Mercitron) have recently raised the debate of the legalisation of euthanasia, alongside criticism of the BBC’s bias favour towards the subject.

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It is important to consider whether euthanasia is morally correct in itself. For me, this argument is overwhelmed via belief in one’s autonomy, which extends to how one dies. In theory rather than practice, euthanasia is a debate of rights. The argument to refute such a position has traditionally been concerned with the sanctity of life, a concept manifesting in much of mainstream religion but which may be held otherwise. However sanctity of life (the value of existing) is too simplistic in contemplating euthanasia. The value of life is far more profound than whether that life is in existence. Pratchett raises the point that it is not the sanctity, but the dignity of life which matters. Thus why should anyone be subject to a painful and suffered anticipation of death? That is not what being alive is about.