WITH the exception of abortion, it is hard to think of a more emotive and contentious area of public debate and medical ethics than assisted dying.

The rest of life demands of us few more agonising choices than those surrounding birth and death.

In late 2010 Margo MacDonald's End of Life Assistance Bill was rejected by 85 votes to 16 at Holyrood. Yet yesterday the Independent MSP was back in the chamber with a new bid to legalise assisted suicide. Her return to this issue, so soon after her first bill was so decisively rejected, testifies to her impressive campaigning zeal on this issue, a zeal intensified by her own Parkinson's diagnosis. It is also a reflection of the way the ground is shifting in this debate. With new members making up one-third of the Scottish Parliament and opinion polls suggesting growing support for the right to be helped to die, it would be a mistake to write off her chances of success this time around.

Even staunch opponents of change must concede that there is a fundamental unfairness when a terminally ill person is so physically incapacitated that he or she is no longer able to take the route of suicide that is open to others. And, while respecting the views of those who believe that only God can decide such matters, it seems unreasonable that those who profess no religious faith should be forced to abide by the same rules.

The recent Commission on Assisted Dying, though not a neutral body, put a powerful case for patients being allowed to kill themselves under strict guidelines. Though the law has been clarified in England, a relative who helps a loved-one to die in Scotland still risks being charged with culpable homicide. Ms MacDonald contends that her new bill addresses some of the shortcomings of its predecessor.

Personal experience tends to colour one's view. That can apply both to watching someone die in agony because of the limitations of palliative care or witnessing callous relatives leaving an elderly person feeling that they are a burden and "best out of it". The fact remains that most doctors continue to oppose assisted dying and are concerned that safeguards offer insufficient protection to the vulnerable. The prospect of such cases falling into the hands of a small group of doctors is worrying. Others fear that it could divert attention from the need to improve palliative care. Could tightening the law make it more difficult for doctors and relatives to come to compassionate and common sense decisions about patients who are near death and in intolerable pain, as they do now with very little likelihood of prosecution? There are no easy answers in this debate but that is no reason to avoid it.