For fifteen years, their best evidence against marriage… was wrong!

For fifteen years, the official line from a major longitudinal study has been that getting married barely matters and that married parents stay together not because they are married, but because they were the sort of people (better educated and better off) who were always more likely to last. New research published this week demolishes this theory. It finds that marriage itself – the lifelong union of one man and one woman, the gold standard for families and society – is what holds families together, and that the evidence pointed that way all along.

The research, from Marriage Foundation, went back to the very data behind the original consensus – 3,324 couples followed for up to fourteen years in the Millennium Cohort Study. That influential study, from the Institute for Fiscal Studies, had concluded that married parents last the course “largely because they are older, better educated, and better off”. Their flaw, the new analysis shows, was to base that finding on “only three quarters of parents in their survey sample”, leaving out the quarter whose data was incomplete – an omission that flipped the result. Put the missing quarter back in, and “marriage accounts for half or more of the gap” in whether parents stay together – whether they marry before, during or after pregnancy, and that this is the case whatever their background.

The new message from that original data is simple. It is not merely that stable people marry, but that marrying itself makes couples more stable. The gap is starkest while children are smallest: in the first three years of a child’s life, cohabiting parents run a 4.1 per cent risk of splitting each year, against 2.5 to 2.7 per cent for married parents. The public promise, made for life, does exactly what marriage has always claimed to do: it binds.

And the timing could hardly be more damning. As I wrote to you last week, ministers are consulting on a plan to hand long-term cohabiting couples the legal rewards of marriage automatically, unless they opt out – removing the very reason to marry at all, just as the evidence confirms how much marriage matters. They call this stance ‘neutral’, but it is the opposite. A government that rewards couples for not marrying, even as the evidence shows marriage is what keeps families together, is not standing back – it is dismantling marriage by stealth, and it is children who will pay.

So this week, do one thing: tell your Member of Parliament about the dramatic new findings, and ask them to recognise and promote real marriage – the lifelong union of one man and one woman – and to throw out this disastrous cohabitation reform before it does its damage. You can find your MP at https://www.theyworkforyou.com.