After entering office in 2010, David Cameron promised to lead "the most open and transparent government in the world", but rarely a month now passes without one of his ministers being rebuked for some act of statistical chicanery. Last December, Jeremy Hunt was ordered by the UK Statistics Authority to correct his false claim that spending on the NHS had risen in real terms "in each of the last two years", then in January, Cameron himself was rapped for stating that the coalition "was paying down Britain’s debts" (the national debt has risen from £828.7bn, or 57.1 per cent of GDP, to £1.19trn, or 75.4 per cent of GDP since May 2010) and then earlier this month, Iain Duncan Smith was rebuked for alleging that 8,000 people moved into work as a result of the introduction of the benefit cap (for which, as I recently revealed on The Staggers, he now faces a grilling from the work and pensions select committee).

Now, Grant Shapps has joined his fellow Conservatives in the data hall of shame. In March, the Tory chairman claimed that "nearly a million people" (878,300) on incapacity benefit had dropped their claims, rather than face a new medical assessment for its successor, the employment and support allowance. The figures, he said, "demonstrate how the welfare system was broken under Labour and why our reforms are so important". The claim was faithfully reported by the Sunday Telegraph but as the UK Statistics Authority has now confirmed in its response to Labour MP Sheila Gilmore (see below), it was entirely fabricated.

In his letter to Shapps and Iain Duncan Smith, UKSA chair Andrew Dilnot writes that the figure conflated "official statistics relating to new claimants of the ESA with official statistics on recipients of the incapacity benefit (IB) who are being migrated across to the ESA". Of the 603,600 incapacity benefit claimants referred for reassessment as part of the introduction of the ESA between March 2011 and May 2012, just 19,700 (somewhat short of Shapps's "nearly a million) abandoned their claims prior to a work capability assessment in the period to May 2012. The figure of 878,300 refers to the total of new claims for the ESA closed before medical assessment from October 2008 to May 2012. Thus, Shapps's suggestion that the 878,300 were pre-existing claimants, who would rather lose their benefits than be exposed as "scroungers", was entirely wrong.

As significantly, there is no evidence that those who abandoned their claims did so for the reasons ascribed by Shapps. Thousands of people move on and off ESA each month, many for the simple reason that their health improves and/or they return to employment before facing a work capability assessment. To suggest, as Shapps did, that all those who dropped their claims were dodging the doctor is sinister nonsense designed to reinforce the worst prejudices about the welfare system.

Fortunately, the newly activist UK Statistics Authority appears intent on tracking Shapps and co. all of the way. Ministers may continue to prefer policy-based evidence to evidence-based policy, but they can no longer do so without consequences.

Update: Labour has now responded to the story, with shadow work and pensions secretary Liam Byrne calling on Shapps "to come clean and apologise for trying to pull the wool over people’s eyes". Here's his full statement:

"This is a Government that doesn’t like to let the facts get in the way of a good story.

"Grant Shapps may know a thing or two about making things up but it really is outrageous that the Tories have been caught yet again misusing statistics for their own ends. People want a Government that deals with the problems facing Britain, with a plan for getting growth and jobs in our economy, not one that repeatedly misleads the public.

"Grant Shapps needs to come clean and apologise for trying to pull the wool over people’s eyes."