The Staggers 10 March 2016 Defeat over Sunday trading heightens the pressure on George Osborne's next Budget The Chancellor is developing an unwelcome reputation among Conservative MPs and activists as error-prone. Photo: Getty Sign UpGet the New Statesman's Morning Call email. Sign-up In 1986, the then-Conservative government was defeated over plans to liberalise Sunday trading. Margaret Thatcher, the sitting Prime Minister, had a majority of 144. Last night, the Conservative government was defeated over plans to liberalise Sunday trading. David Cameron, the sitting Prime Minister, has a majority of 12. 27 Conservative MPs broke the whip to hand the government a defeat. The government's whips have responded well to an election that was a Conservative victory, but a thumping reduction in the government's majority (down from 77 under the coalition to just 12 now), and in a way, the surprise is that a defeat hadn't happened before. (That said, Tory whips believed that, had tax credits returned to the House of Commons following its defeat in the Lords, passing it again would have proved impossible). But there's a particular sense that the government - and particularly George Osborne - blundered into a battle that they were only going to be defeated over. Changes to Sunday trading were not in the Conservative manifesto, and there isn't a great groundswell of public feeling about the issue one way or the other. One Tory MP recently reflected to me that, had it not been for John McDonnell's Little Red Book gaffe, the spending review would have been "an unqualified disaster" for Osborne, and that his pre-election Budget - which saddled the party with line that it would "cut spending to 1930s-levels" was not the stuff that dreams are made of, either. Osborne is developing a reputation for unforced errors. Among MPs, that is unlikely to matter. Conservative MPs believe that, while Jeremy Corbyn is leader, they will easily defeat Labour at the next election. But among Conservative members, there is an element that genuinely fears the prospect of a Corbyn-led government. A reputation for own goals could yet cost the Chancellor dear. › George Osborne’s stock has fallen, but it’s too soon to write off his leadership hopes Stephen Bush is political editor of the New Statesman. His daily briefing, Morning Call, provides a quick and essential guide to domestic and global politics. Subscribe For more great writing from our award-winning journalists subscribe for just £1 per month!