Why do men kill their children?

This most tragic, illogical crime begs a vital question.

WE WILL never know for sure what went on in Stephen Carter's mind as he killed his three children at the weekend. Lucy, aged seven, Thomas, aged four, and three-year-old Holly died in the family car. It appears that they were drugged before Mr Carter set the car alight. Then he hanged himself from a nearby tree. Suddenly, a family had been wiped out, leaving the mother, Teresa Carter, to live with her terrible loss. Mrs Carter has been left utterly powerless, with no possibility of setting matters right and, because her husband is also dead, no chance of thoroughly understanding why he killed their children.

The danger is that the rush to explain will lead to blame being settled upon the bereaved, who are already overburdened Psychobabbling is entertaining, but it can be dangerous. Those who lose family through a suicide are much more likely than the average person to kill themselves. We need to bear Mrs Carter's welfare closely in mind.

Yet you can already see the story being constructed in terms which say that everything would have been all right had Mrs Carter been a loyal wife. A tragedy is fast being turned into a morality tale.

Mrs Carter had left the family for a year, then had become reconciled only seven weeks ago. Her husband apparently feared that she was about to leave again. That must have been very distressing for him. But it is worth remembering that it is commonplace for women and, indeed, men, to be left alone with their children, deserted by their partners. They usually survive. Suicide and murder rarely follow. So to understand why everything turned out so terribly wrong in this case, you need to know the complex psychological details of this particular family, this particular man.

This is also true of other cases, for although such instances of mass killing are unusual, they happen with some regularity. In February, Kenneth McKay slit his throat after knifing his two children, while their mother screamed for help. McKay died. The children survived. The couple had had a long history of domestic disputes and had split up some months before.

In January, Paul Madin, a 37-year-old mechanic from Derbyshire, died in a burning car with his two children, a month after his partner had left him. Mr Madin had been depressed and had talked of suicide. When passers-by tried to pull him from the burning vehicle, he pushed them aside.

We may never discover the secrets of such tragedies, but it is possible to resolve one paradox: how can a man love his children, and yet kill them? There are many possible reasons for such extreme action. There was, for example, once a patient at Scotland's maximum-security hospital in Carstairs, who had suffered a "pathological sense of altruism". He killed his family after developing an acute sense of the danger that they faced in the world. He perceived killing them as an act of kindness.

The man eventually recovered, and then had to deal with the horror of what he had done.

"A man might see himself as the lone protector of his children against a powerful and evil threat," explains Avi Shmueli, a marital psychotherapist at London's Tavistock Marital Studies Institute. A deranged mind may well identify the loss of a mother and wife, or the break-up of a family, as just such a threat, he says.

"The father may feel that he could in some way immortalise himself and his children - put them beyond harm and hurt - by dying himself, after taking their lives."

It may come as a surprise to some people that a man can become so intensely involved with his children as this, especially given the conventional wisdom that fathers tend to be marginal figures in families. But Avi Shmueli is unsurprised : "A father can feel just as much as a mother about his children. Those feelings may not be as accessible but they can be just as intense."

However, you cannot escape the truth that killing a child is also a highly aggressive act, in particular towards the mother.

"It can be an act of huge anger. The father has taken away her power, leaving her with nothing she can do," explains Shmueli. So why, you wonder, don't men in these circumstances kill their wives instead of their children?

"There may be a very good reason," he says. "It could be that the man realises that if he kills his wife he will end up in jail for life and he will lose his children. So that is no solution if he is trying to protect them. There is something about killing them and himself which means that he both hurts the person he thinks can damage them, and places all of them beyond being hurt ever again."