The Staggers 15 July 2013 Duncan Smith rejects evidence-based policy: "I believe this to be true" There's no evidence for his claim that 8,000 people moved into work as a result of the benefit cap but he "believes" it regardless. Sign UpGet the New Statesman's Morning Call email. Sign-up I've already told you five things Iain Duncan Smith doesn't want you to know about the benefit cap (which is introduced nationally today), but I couldn't allow his egregious interview on the Today progamme this morning to pass without comment. Early on in his duel with John Humphrys, the Work and Pensions Secretary declared that the homelessness figures had "hardly moved". The reality? Homelessness in England is up by 27 per cent since the government came to power in 2010. Later challenged over his claim that 8,000 people moved into work as a result of the benefit cap (a statement that the UK Statistics Authority said was "unsupported by the official statistics"), Duncan Smith decided to dispense with any pretence of evidence-based policy. "I believe this to be true!" he cried, demonstrating the same faith-based approach that led George Osborne to believe that cutting public spending in the middle of a slump would lead to higher growth. He told Humphrys: The reality is, I believe that to be right. I believe that we are already seeing people go back to work, who were not going to go back to work until they were assured of the cap. Any remaining ambition that David Cameron had to lead the "the most open and transparent government in the world" finally died with those words. P.S. In an apparent fulfilment of his prophecy that "too many tweets might make a twat", David Cameron tweeted this morning. We're rolling out a cap on Benefits today - @IDS_MP and I are determined to make work pay, and help the UK compete on the #GlobalRace. — David Cameron (@David_Cameron) July 15, 2013 Unfortunately for Cameron, @IDS_MP is not, as he thought, the Work and Pensions Secretary but a spoof account whose recent tweets include "I've always supported a Mansion Tax. Your Tax buys my Mansion. Chin chin!" and "A thrifty way to keep cool in this heat wave is to dab the ice from your Champagne bucket onto your forehead." A thrifty way to keep cool in this heat wave is to dab the ice from your Champagne bucket onto your forehead. — Iain Duncan Smith MP (@IDS_MP) July 13, 2013 › Is social media data in finance a double-edged sword? Iain Duncan Smith arrives for a cabinet meeting at 10 Downing Street. Photograph: Getty Images. George Eaton is senior online editor of the New Statesman. Subscribe For daily analysis & more political coverage from Westminster and beyond subscribe for just £1 per month!