Mary Dejevsky: Why marriage is a dangerous game in politics

The M word is storming back - M for marriage, that is. When Iain Duncan Smith launches Breakthrough Britain - the second part of his Social Justice Commission report - today, he will argue for a reorientation of the tax and benefits system to support the institution of marriage. David Cameron has already nodded his approval. "Marriage," he said in a weekend interview, "is a good institution. It should be supported. It should be recognised in the tax system."

There is no reason to doubt the sincerity of either man. Both Mr Duncan Smith and Mr Cameron evidently exist in a blissfully wedded state and both have deployed their highly presentable wives as electoral assets. Their endorsement of marriage has been met with hugs and kisses by Conservative commentators, and a similar reception surely awaits in the Shires. Personally, who can fault them? Politically, they are making a gigantic mistake.

The mistake is not about wanting less family breakdown. It is not only Mr Duncan Smith's Social Justice Commission that is disturbed by the state of British family. We have the highest rates of teenage pregnancy and single motherhood in the developed world. We have high levels of juvenile crime and anti-social behaviour, and our children are among the most stressed and least happy anywhere.

Perhaps the most striking statistic, though, is the one Mr Duncan Smith cited in his interim report, Breakdown Britain. It is that half of all unmarried couples separate before their child is five, compared with one in 12 couples who are married. This, for Mr Cameron and others, is what clinches the argument. Marriage offers the best prospect of stability for children; this is why it should be supported.

By staking so much on the M word, however, Mr Cameron is playing straight into the hands of his new adversary. Gordon Brown has stated many times that his primary concern is the welfare of children. If this has the effect of stacking the tax and benefits system in other ways, then so be it. Children should not be made to suffer for the behaviour of their parents.

In so saying, Mr Brown casts himself as the enlightened upholder of a modern morality and clears the way for Mr Cameron to be portrayed as a stiff-collared Victorian. Mr Brown can then leave it to his minions to talk about the suffering caused - especially to women - by the unforgiving rigidity of Victorian values. A few sepia-scenes of Dickensian despair, and the election is as good as in the bag. Even the Shires now have their fair share of divorces, single parents and civil partners.

This is not to say, however, that the Conservatives do not have a point, and a compelling one, when they take issue with the current benefits arrangements. It is perverse for ministers to say they want to discourage teenage girls from getting pregnant, men from shirking their parental responsibilities and families from breaking up, when the financial and social provisions work quite the opposite way. No amount of sex education, morning-after pills and child support demands will trump the awkward realities.

A young woman from a modest home can improve her life by getting pregnant. Anyone who says this tends to be shouted down as vindictive; the middle classes simply find it hard to believe, because they do not understand the wretchedness of her previous condition. But pregnancy invariably speeds a move out of an overcrowded house or flat into somewhere that is hers and brings more security and independence than she has ever had. From her point of view, pregnancy is a reasonable choice.

As is living apart, for low-income couples with a child or two. The benefits - in housing allocation, housing benefit and tax credits - for a single person responsible for a child vastly outweigh any financial contribution a partner can make until he or she is quite far up the income scale. It is less that the system encourages couples to split, than that it discourages them from living together as a family. The financial penalty is too great.

What is more, there are almost no circumstances where an individual with two children and a low wage will be better off living with a partner. The women get used to ordering their own lives, the men drift away, and the only check made by social services is that they are not cohabiting. The number of couples described as "living apart together" has rocketed. No wonder there is a housing shortage. The root problem is not any conscious rejection of marriage, but the way the current system penalises two-parent low-income families, whether they cohabit or marry.

Mr Cameron would make his political life much simpler - and trump Mr Brown's child poverty card - if he pledged to lift the financial penalty for all cohabiting parents. Instead of the M word, he should try the F word - F for families in all their 21st-century diversity.

m.dejevsky@independent.co.uk

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