For 14 years, the Tories presided over a muddle of unrealistic pledges. Labour should try a little honesty instead

• Jonathan Portes is professor of economics and public policy at King’s College London and a former senior civil servant

Yesterday Kemi Badenoch said the Conservative government “got it wrong” on immigration, and promised a “strict numerical cap”.

We’ve been here before. In the summer of 2010, I was chief economist at the Cabinet Office. Not long after the election, I sent David Cameron an unsolicited paper about his pledge to reduce migration to the “tens of thousands”. It said that this would almost certainly present him with the unpalatable choice between deliberately damaging the UK economy and labour market, and conspicuously failing to deliver a high-profile political commitment. I suggested, gently, ways in which the target could be modified.

Jonathan Portes is professor of economics and public policy at King’s College London and a former senior civil servant