28/02/2014 11:51 GMT | Updated 30/04/2014 06:59 BST

Why Iain Duncan Smith and George Osborne Are Wrong on Child Poverty

Writing in the Guardian's Comment is Free to launch the government's new Child Poverty Strategy, Iain Duncan Smith and George Osborne talked about 'measures that recognise the root causes of poverty: entrenched worklessness, family breakdown, problem debt, drug and alcohol dependency'. This is, undeniably, a list of bad things. Who, after all, is seriously going to stand on a pro-drug addiction or 'unemployment for all' platform? But the assertion of a causal link running from this hit list to poverty is made without evidence.

Take 'entrenched worklessness'. This is nowhere near as significant a phenomenon as the government likes to imply. DWP statistics show that rates of worklessness fell between 1997 and 2013 from 16.2% to 12.2% in households with children. Official figures also show that the vast majority of 'poor' parents have worked, are in work, and are likely to work again in the near future. And famously, when academic researchers went looking for the three generations of families who have never worked that Duncan Smith is so fond of referencing, they were unable - despite strenuous efforts - to find a single example.

Osborne and Duncan Smith also identify family breakdown as a driver of poverty, but breathe on it and this assertion falls down. The truth is that 71% of poor children live in a couple household and only 29% in a single parent household. Rich families get divorced; poor families get divorced. How you feel about that is more of a moral or social personal preference.

It is true that children in single parent households have a higher risk of poverty - 22% compared with 16% for a couple with children. But single parent families saw the biggest drop of all in poverty under the last government - from 49% in 1997/98 to 22% in 2010/11. So rather than prove that separation is a one-way track to poverty, what this evidence tells us is that poverty is policy responsive, and risks can be reduced by the right actions.

The government's logic is even more questionable on debt. Perhaps surprisingly, debt is fairly evenly distributed: across all income groups, 40-50% of people have some form of non-mortgage borrowing, with the poorest fifth no more likely to have debt than those in the upper-middle. Self-evidently, however, debt is more likely to be a problem for those on low incomes. Despite the fact that they are the most reluctant to borrow, they are also the least able to keep out of the market, often to smooth out the fluctuations in their incomes. So debt is much more a symptom of not having enough money, rather than its cause.

Finally, Duncan Smith and Osborne are right to say in their article that "governments have not collected proper data on the number of children being raised by drug or alcohol addicted parents". Curiously, this hasn't stopped them repeatedly asserting that this is one of the key drivers of poverty. But what evidence we have suggests that, compared with the numbers living in poverty, the scale of these problems is small. One estimate suggests that just 2.7% of all couples with children (not just those living in poverty) include an alcohol dependent parent, and just 0.9% include a drug dependent parent. Addiction is another problem that harms families of all classes, including the wealthiest, as some high profile and tragic cases have recently shown.

The main cause of poverty remains lack of an adequate income. When those on low incomes are set to lose £22billion a year from social security, tax credits and other basic support by the end of this Parliament, the results are depressingly inevitable: projections from the Institute for Fiscal Studies suggest that child poverty will increase vastly from 2.3million children at the start of the coalition's term in office to 3.2million by 2020 if their current policies continue.

Child poverty costs this country £29billion a year, and will rise to £35billion by 2020 if the projections prove accurate. Other countries are doing far better on the existing - internationally recognised - measures. It's not the child poverty targets that are 'discredited', but the government's approach to meeting them.

Parents want secure jobs, living wages, fair rents and affordable childcare. This should not be too much to ask in one of the world's richest economies, yet these things remain out of reach for millions of families. At the heart of the strategy should be the promise that, as the economy grows again, those at bottom will gain more than those at the top. This will need strong wage growth for the lowest paid, more job security and affordable rents; and that means taking tough decisions that have been dodged in the new draft strategy to stop those at the top running off with all the proceeds of growth.