As had been predicted, most MSPs felt themselves unable to support Margo MacDonald's End of Life Assistance (Scotland) Bill at its stage 1 debate yesterday and the bill has fallen.

Contributions to the debate, in which many members expressed deeply held views, were both sincere and cross party, many speaking from personal experience. They did of course display a fundamental philosophical difference between the two sides.

At the heart of the argument is the weight to be given to personal autonomy against the perceived interests of society, in deciding whether killing should be legalised in any circumstances. The arguments in favour of autonomy often seem to me to carry a "Yes, man is an island" undertone, a denial that personal choices of this nature can impact on the rest of us. That is surely wrong. Knowledge that a particular type of behaviour is legal, and is practised, must change attitudes and is bound to lead to cases that push at the boundaries of what is permitted.

To use an illustration, the social acceptability of divorce has grown as the divorce rate itself has increased. One can argue whether the effects on society of a high divorce rate are on balance positive, or negative, or neither; but it would be hard to say that they do not exist.

To say that is not in any way to equate divorce and assisted dying, or to suggest that assisted dying would ever become as commonplace; but it helps demonstrate why there is a wider societal interest, particularly on a matter of life or death, that makes it a legitimate standpoint to say that autonomy does not stand above other considerations. And it is from that starting point that possible effects on the disabled, or chronically ill, or elderly requiring ongoing nursing care, should be assessed.

I should say that if I had taken part in the vote, I too would have been against the bill, from an ethical and faith based standpoint. But although many members chose to take such a position in opposing the bill, the committee which examined it, probably on purpose, chose to look rather at its technical merits, and its report recommending against the measure did so on the basis of perceived flaws in the way it was drafted.

Among its objections were that the proposed standard of finding life "intolerable" is inherently subjective, and given Ms MacDonald's emphasis on the wishes and self determination of the requesting person, cannot stand up as an objective test; and that there are "immense difficulties" in drafting a provision that would catch those intended without extending also to whole other groups, and also with the definition of "terminal ilness" and the eligibility requirement based on inability to live independently.

These points give rise to interesting questions, which I think should be further explored, of whether any such law could be written so as to demarcate with reasonable clarity those who can and cannot take advantage of it, without leaving itself open to charges of operating in a discriminatory way. And if it cannot, is that a sufficient reason not to pass it, even if we were to accept in principle that there are cases where personal autonomy should be given effect?

It has been argued, for example, that a disabled person who did not meet the tests laid down by any such legislation but who wished to end their life because of their condition, would be able to claim that the law discriminated against them as a disabled person on that account. If that is correct (and I am not in a position to give an expert view), it seems to me that there is no place the law could stop short of permitting anyone with any kind of physical or mental impairment from taking this step.

Another problem is those with a mental disability. On the face of it, the more severe the disability, the more likely they would be to meet any statutory test; but also the greater the difficulty in determining their capacity tomake the necessary choice. It is not difficult to see why the committee considered that there was such difficulty in drafting.

If those isues cannot be resolved, can it be right to pass any law? I suggest not, if the law would then be open to challenge in such a way that policy based restrictions would inevitably be overridden. So although it may at first sight look like a second best option to have some published guidelines as to when a case of assistance might be prosecuted and when not, as in England, it may be that we have to accept that this is the most practical way forward.

It seems to me, then, that we should be able to expect from Crown Office something similar to the guidance now issued by the Director of Public Prosecutions. If it is not forthcoming, is there any reason why a human rights challenge such as that brought by Debbie Purdy would fail?

Pro-bill campaigners point to opinion polls, said to show that about 75-80% of the public favour the right to choose in cases of great suffering. But I wonder what the figure would be if people had to address the more difficult issues highlighted by the committee. And are MSPs bound to follow what they perceive to be the public mood, on this or any other issue? Surely not, because an MSP should not be obliged to vote against their own conscience but should be expected to vote in accordance with what they see as the public good, and will have to answer in due course to the electorate. I suggest that if our elected representatives had not been free to vote in this way, we would never have abolished the death penalty in the UK when we did, and might still have it.

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