The parents, not judges, should decide the future of these conjoined twins

There are no moral absolutes in the case of the conjoined twins known as Jodie and Mary - now six weeks old - on whose fate the Court of Appeal ponders this week. There are three approaches, each of which could be deemed to be absolute. There is the utilitarian calculation that assumes that the survival of the stronger child at the expense of the weaker is morally a better outcome than the death of both, which is the certain result of the failure to intervene medically. That was the judgment of the lower court and, given the strongly utilitarian tradition of English law, is likely to be the ruling of the Court of Appeal next week.

There are no moral absolutes in the case of the conjoined twins known as Jodie and Mary - now six weeks old - on whose fate the Court of Appeal ponders this week. There are three approaches, each of which could be deemed to be absolute. There is the utilitarian calculation that assumes that the survival of the stronger child at the expense of the weaker is morally a better outcome than the death of both, which is the certain result of the failure to intervene medically. That was the judgment of the lower court and, given the strongly utilitarian tradition of English law, is likely to be the ruling of the Court of Appeal next week.

But there are two other possible absolutes. The first is the right to life. If that right is absolute, then it must be upheld for the weaker child as much as for the stronger. On that basis, no one can have the right to decide on the weaker child's behalf that she would choose - if she were competent to decide - to curtail even her short and ailing life for the sake of her sister's survival.

The second is the right of parents to decide their children's future. Some have attempted to dismiss the parents' assertion of that right by describing it as stemming from their "deeply held religious beliefs", used here as a euphemism for irrationality and obscurantism. But there is a perfectly rational argument for saying that it is parents who are in the best position to judge what is in the best interests of their own children.

Of course, the truth is that all three of those approaches should be balanced in the circumstances of any particular case - and especially in this difficult case. The utilitarian calculation cannot be absolute, because it involves the deliberate taking of another life. The right to life cannot be absolute, because all but the most zealous pro-lifer would accept that abortion is the lesser evil in situations where there is a threat to a mother's life, or where a foetus would go to term with some fatal disability.

And the parents' right to decide cannot be absolute, because the state has justifiable grounds to intervene in cases such as when Jehovah's Witnesses refuse routine medical treatment for life-threatening conditions.

In the end it is with the parents that this agonising decision best belongs. In considering the best interests of the children, the parents have had in mind both the needs of the weaker twin - who will die as soon as she is separated - and the stronger twin, who, if she survives, will be doomed to a life of disability. Some have criticised the children's parents for saying they do not want to bring up a disabled child because of the attitudes toward disability of their relatively poor Mediterranean island society (although it's not as if disabled children are particularly well treated in Britain). But the point is that the burden of bringing up a severely disabled child is not necessarily one that the courts have the right to impose on unwilling parents.

But there is a more powerful point. It should not be the role of the courts to force these unhappy parents into choosing to kill one of their babies in order that the other should survive. The horror of making such a choice will be self-evident to any parent. The pity is that this decision was ever placed before the courts instead of being left where it belongs, with the parents who will have to live with the consequences of the decision long after the rest of us have forgotten this very sad case.