Boris Johnson has been accused of misleading MPs over his claims of low reoffending rates at Feltham Young Offenders Institute. Since last November, the Mayor has been telling all and sundry - including a Home Office Select Committee - that a new unit had slashed reoffending rates from 80% to less than 20%.
However, the BBC's Tim Donovan looked into these claims and found that staff in the Heron Unit, as well as senior civil servants, have been saying for some time that these stats were at too early a stage to be used in public. They only covered former inmates who'd been released a few weeks (a true picture is only revealed after about a year). In addition, the '80%' rate is a national reoffending figure and doesn't necessarily relate to the specially selected, already willing to change, young offenders at Feltham.
The chair of the UK Statistics Authority has now written to the Home Office Select Committee (PDF) saying the claims "do not stand up to scrutiny" and that Boris ignored warnings about the dodginess of the numbers he was using. Either the Mayor doesn't understand how stats work (we all know he's not a 'details man'), his officials didn't pass on the warnings or he decided to plough ahead regardless.
Why is it important that he didn't wilfully mislead a parliamentary select committee? Well, when these groups make recommendations on how public money should be spent, they need to have the correct information before them. Otherwise taxpayers' cash could be spunked on projects that have no meaningful benefits.