What a lot of steam has been generated over the past weeks about the amount of time mothers spend with their children. The assumption made by Professor Kathleen Marshall, Scotland’s £72,000-a-year children’s czar, is “more time, good, less time, bad” and this is the origin of her suggestion that single mothers be paid to stay at home and chalk up “real and valuable contact” with their offspring.

In a dozy armchair way — nodding while half asleep — this suggestion makes sense. Contact between mother and child, except in cases we would all recognise as abusive, is a good thing. The trouble is, as Marshall should be the first to recognise, we are way beyond armchair policy these days.

At the beginning of the 21st century, there certainly are concerns about the amount of time parents and children spend in each other’s company. But it’s the whole concept of parental responsibility, and what that means, that has gone awry. Get that right, with parents looking first to their children’s welfare, and the time-spent-with-the-kids factor might sort itself out. Concentrate solely on the time-spent-with-kids factor, as Marshall is doing, and you leave the fundamental problem of parental responsibility unaddressed.

Consider the single mother who goes out to work, returns home to her child, cooks a healthy dinner, plays with the child, reads him or her a story then puts him or her to bed. Compare that with the single mother who doesn’t work, has no structure to her days, spends benefit money on junk food and, because she is with her child all day, makes no special effort to play with or read to him or her. Which of these children has “real and valuable contact” with an adult? The flaw in the suggestion that single mothers be paid to stay at home is obvious. It assumes all single mothers are the same: responsible but thwarted. Yet this is as nonsensical as saying all children of affluent couples are properly nurtured.

Single mothers come in all shapes. Paying them to stay at home will not turn them into a homogeneous mob of perfect parents. Nor will it ensure their young children lead emotionally and socially balanced lives.

Nevertheless, since young children need their mothers, the current debate is not without merit.

What we should know by now, however, is that the state cannot provide the answers. For a start, it is too blunt an instrument to deal with anything as idiosyncratic as parenting. Moreover, by turning single motherhood into a state-sponsored job, the very nature of motherhood is distorted.

It may feel like a job — it certainly does when I’m doing the laundry — but it is not. Motherhood is a peculiar kind of gift. Once we lose sight of that, we’re in real trouble. And then what does the state picking up the tab for stay-at-home single mothers say to fathers of their children? It says: “We’ll pay, so don’t you bother.”

As Jill Kirby of the Centre for Policy Studies pointed out, when the state steps forward, the father steps back.

Yet to flourish, as all studies prove, children should have two parents and preferably two who wish to stay together. To offer financial inducements that, in effect, turn single parenthood into a career opportunity is an odd way of helping children.

Furthermore, the idea of paying stay-at-home mothers the equivalent of a salary is illogical. A real salary can be withdrawn if the work for which it is exchanged is not up to scratch. If a state-supported, stay-at-home mum turns out to be spending her support on heroin, vodka, a boyfriend’s crack habit or just on clothes and cinema tickets, can this support be withdrawn? The taxpayer might get pretty shirty if he or she (another mother trying to service a mortgage and feed her children as the government says she should, perhaps) discovers that her neighbour is living a rather easier life at her expense. I can think of few things more likely to cause social division.

If we really want children to benefit from parental “quality time”, one answer seems obvious.

Instead of paying single mothers not to work, we should promote and encourage the kind of stable family life that only in the rarest of circumstances actually leaves a mother on her own.

Whether a mother works or not should be a decision a child’s parents take together, with both acknowledging the needs, financial and emotional, of the human life they have created.

When a father and a mother take joint responsibility for a child, there is twice the chance of that child getting some valuable contact time. Is not this the proper way forward? I accept the notion of promoting stable, two-parent family life is old-fashioned and out of tune with our “anything goes” society. But surely a children’s commissioner should find the courage at least to bring it into the debate.

Just demanding more state intervention for single mothers may win approving smiles from those who believe the state should sort everything, but it gets nowhere near the heart of the problem.

A real children’s champion would get out of that armchair and subject the concept of “valuable contact time” to the cold light of day. Sadly, there seems little appetite for such scrutiny at the moment, so children will be the losers again.

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