The Home Secretary has apologised in Parliament for the premature release of data suggesting that police were making headway against knife crime.

Jacqui Smith admitted today that the Government was “too quick off the mark” when it released figures last Thursday showing an apparent fall in the number of teenage stab victims. She told MPs today: “I am sorry that I think we were too quick off the mark with the publication of one number in relation to the progress that had been made with tackling knife crime.”

Ms Smith came under fire from her Tory shadow Dominic Grieve, who accused the Home Office of leaking information when it suited ministers for “political purposes.”

The row over the release of the knife crime data blew up on Friday when the chairman of the UK Statistics Authority, Sir Michael Scholar, spoke out publicly against the Government’s “premature, irregular and selective” use of the statistics. Sir Michael said ministers had breached the code of conduct which they had themselves approved to fend off accusations of spin.

During question time today Mr Grieve asked Ms Smith: “Isn’t one of the reasons why there are so many unauthorised disclosures in the Home Office, the fact that your department sets the example by engaging in authorised leaking when it suits your party’s political purposes?

“In this context did you authorise the leak last week of partial and selective knife crime statistics in breach of the Government’s own rules and against of the UK’s own statistical authority, or was that all down to the Cabinet Office and Downing Street?”

Ms Smith hit back: “There are lots of arguments about the definition of a leak but I hardly think issuing a press release counts as a leak.”

She then went on to apologise in relation to the early release of the statistics and added: “I would like to commend the police and their crime-fighting partners for the impact that they are already making through the tackling knives action programme as spelt out by the other statistics produced last week.”

In the press release in question, Ms Smith announced that there had been an overall fall in the number of people caught carrying knives and claimed that those found guilty of possessing knives were receiving longer sentences.

But the Home Office was unable to provide the statistics to support the claims, saying they were “interim findings”.

A Home Office factsheet claimed hospital admissions were down 27 per cent since the crackdown on knife crime in ten areas began in July and stated there had been 18 per cent fewer victims under 20 in London between April and September 2008 than in the same period in 2007.

The figures topped morning news bulletins on BBC Radio 4

Sir Michael wrote to Jeremy Heywood, permanent secretary at 10 Downing Street, and said that figures on hospital admissions for stabbing injuries had not been properly checked and putting them out early was “corrosive of public trust”.

He said in his letter that he had been told that officials or advisors in Number 10 had “caused” the Home Office to issue the release.

The statisticians who produced the figures attempted to block their release on the grounds it was in breach of the National Statistics Code of Practice.

Sir Michael said: “These statistics were not due for publication for some time and had not therefore been through the regular process of checking and quality assurance.

“The statisticians who produced them, together with the National Statistician, tried unsuccessfully to prevent their premature, irregular and selective release.

“I hope you will agree that the publication of prematurely released and unchecked statistics is corrosive of public trust in official statistics and incompatible with the high standards which we are all seeking to establish.

“I would be grateful for your comments and for your assurance that there will be no repetition of this breach of the National Statistics Code of Practice.”

Professor David Hand, head of the Royal Statistical Society, highlighted “serious” bad practices during the release of immigration figures in August.

The latest row over is damaging for the Government as it once again casts doubt on whether people can believe official statistics on crime - an area where ministers are struggling to convince the public that offending is falling.

In October the Home Office was forced to admit that serious violent crime is much worse than they had been claiming because police forces had been failing to record offences properly.

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