The claim: "The Centre for Social Justice estimates, the cost of family breakdown is £20-24 billion. And the Relationships Foundation puts the figure at nearer £40 billion.
"The fact remains that these are huge numbers — yet they represent just the direct costs. The costs to society as a whole through social breakdown, addiction, crime, lost productivity and tax revenues are very difficult to quantify — but research suggests they could be up to £100 billion." - Iain Duncan Smith, Secretary of State for Work and Pensions.
Mr Duncan Smith made these claims during a speech at the Annual General Meeting for relationships charity Relate.
His theme was the importance of the two-parent family, and much of the speech was dedicated to outlining social and financial costs of "family breakdown".
The first dilemma arising from the Work and Pensions Secretary's statement is the ambiguity of exactly what he is claiming.
For instance, was the Press Association justified in paraphrase the above quotation and have Mr Duncan Smith implying that "the 'abandoning' of policies that support marriage has cost the country up to £100 billion"?
Similarly, when the Daily Mail headline proclaims the "£100 bn cost of broken homes", is this a fair reflection of the original claim?
A straightforward link is not quite made explicit, but the insinuation that the £100 billion figure is constructed from direct and indirect consequences of "family breakdown" is fairly strong.
Strong enough, Full Fact believes, for the papers to claim legitimacy in their cropping.
Where the notion that broken families come with a £100 billion price tag originates from matters, because somewhere along there way there seems to have been an error: as far as we can discern, there is no clear evidence to support this claim.
The 2006 report from the Centre for Social Justice (CSJ) to which Mr Duncan Smith referred was produced under the auspices of his own Chairmanship.
It was a self-confessedly inexact measure relying on inflations from a previous estimate made six years earlier, but the Welfare Secretary is right that it refers only to direct consequences.
Not so the estimate from the Relationship Foundation.
Their 2007 document aims to "address the costs in five broad areas — tax and benefits, housing, health and social care, criminal justice, and education".
This seems to include many of the categories cited by Iain Duncan Smith in the £100 billion he cites.
If anything, this figure includes some projections that may overstate the total figure.
Several billion pounds of the total arises from the costs of dealing with domestic violence, for which falling marriage rates can hardly take the full blame.
Others are extremely speculative: rising costs of housing the elderly are blamed partly on "relationship breakdown" between parents and their children.
Perhaps most contentiously, the authors consistently assume direct, one-way causal links between family breakdown and social problems. It is quite plausible that much of the causality could act in the opposite direction, or that various "third factors" - whether cultural, socio-economic or otherwise — account for the correlation.
But even if we accepted the Foundation's findings unequivocally, with all their extrapolations for the indirect effects of family breakdown, the total would still only come to £37 billion.
Perhaps Mr Duncan Smith taking this figure and mistakenly double-counting many of the "indirect" consequences that it already includes.
Perhaps he has confused the CSJ's £100 billion estimate for "social breakdown" with the £24 billion estimate for "family breakdown", which was included in this figure.
Or perhaps Full Fact is simply unaware of yet another radically higher estimate of the cost.
We contacted Mr Duncan Smith's office to find out which was the case, but so far we have not heard back from them on this matter.
Without further enlightenment, we can see no reason to accept the claim now in circulation that "broken homes" cost Britain £100 billion.
And whether or not this was indeed what the Work and Pensions Secretary intended to say, his statement did appear to carry this implication. This in turn has given rise to headlines in the press which will receive far more pubic exposure than the original wording.
Given the complex nature of this issue, any projections are bound to include a large amount of assumption and speculation.
Indeed the very CSJ report from which the lower estimate is extracted warns against certainty in this area: "it is impossible to quantify with any accuracy the cost of family breakdown to the Exchequer".
However, these cautions are academic to the claim at hand, since none of the available estimates, however rough, seem to support it.
Edgar Gerrard Hughes
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