The Mayor made the remark at Mayor’s Question Time as he faced questions over his “misuse” of statistics relating to the success of the City Hall backed Heron unit at Feltham Young Offenders Institute.
The unit aims to help young offenders back into work or education on release and prevent re-offending.
Appearing a committee of MPs, the Mayor claimed the unit cut re-offending rates to 19%.
However, a BBC London investigation revealed the true rate is at least 40% and that City Hall officials “were told expressly that the mayor’s claims were unreliable, based on anecdotal evidence and should not be made public.”
Sir Michael wrote to the Home Affairs select committee, informing MPs that “The mayor’s evidence to your committee is not supported by the Ministry of Justice’s published statistics… nor is it supported by any statistical analysis published by the mayor.”
In March the watchdog rebuked Johnson over crime statistics, saying City Hall’s use of the figures “as part of a media event to publicise the success of your policies, some time ahead of their normal release date” was “poor practice, and was damaging to public trust in the statistics produced by Transport for London.”
Scholar asked the Mayor to sign up to the Code of Practice on the use of official statistics, but the Mayor declined to do so.
AMs have previously expressed concern over the Mayor’s use of housing statistics.
Questioned this morning by Labour’s Joanne McCartney, Johnson denied misleading MPs, and insisted: “If I erred, it was not in saying these figures are temporary, they are provisional, they do not represent a final analysis, and we will have to see how the Heron unit fares in succeeding years and months.”
The Mayor told AMs: “There’s this guy called Scholar who writes me letters who appears to be some kind of Labour stooge…I’m not impressed by the conduct of that particular body and its chief.”
Responding to the Mayor’s comments, a UK Statistics Authority spokesman said: “The Mayor is entitled to his views.
“The independence of the Statistics Authority and its Chairman are evident from our published correspondence and reports.”
Will Moy, Director at Full Fact, an independent factchecking organisation, said: “The Mayor’s slight on Sir Michael Scholar is hugely misplaced. He is a former civil servant, was a Permanent Secretary under Conservative and Labour governments, and a Private Secretary to Margaret Thatcher.
“More importantly, he has carried out his important duties robustly but with impeccable impartiality. He has criticised senior members of both parties when that was called for by the Code of the Practice for Official Statistics.
“People who care about public trust in official statistics will be disappointed by today’s slur on one its champions.
