Sir Michael said public trust in official figures was at a low
Ministers should not be shown official statistics before they are released, government statistics chief Sir Michael Scholar has said.
People did not trust official figures and thought politicians were "able to get at them", he told the BBC.
He said last month's premature release of knife crime statistics was just one example of figures being leaked.
Ministers are currently allowed to see official statistics 24 hours early, to allow them to prepare their response.
Figures suggesting there had been a 27% fall in hospital admissions for stab wounds were used by the government during an announcement on knife crime last month.
But Home Secretary Jacqui Smith apologised for being "too quick off the mark" after Sir Michael, the head of the UK Statistics Authority, complained that the figures had not been through proper checks and quality assurance.
The government was attacked by the Conservatives and Liberal Democrats, who said they had been "caught peddling dodgy statistics" and accused them of "manipulative spinning".
On Friday Sir Michael told BBC Radio 4's World at One programme the knife crime data episode had been a "separate issue", adding: "It is centrally related to the trust agenda.
"People don't trust official statistics, they think politicians and political advisers have been able to get at them."
He said the UK should "move to a system in which everybody gets the figures at the same time", objectively produced by professional statisticians and "handed over at the same time to all sides of the political debate".
"That is when the politics should start. It shouldn't start while the numbers are being produced."
Sir Michael said public trust was at a low level and needed to be addressed.
"There have been incidences, there has been some in recent months, in which politicians - ministers and their political advisers, who have the figures in advance of the general public and Parliament have then leaked them, have put them out selectively to help them in a political argument which they are advancing."