Downing Street has defended the senior civil servant who joked about working while drunk and mocked the government's campaign against binge drinking.
A Number 10 spokeswoman said the prime minister had "a high regard" for Louise Casey, 38, who is director of the Home Office's anti-social behaviour unit.
The spokeswoman said her comments had to be "put into perspective" as they were made in an after dinner speech.
She said people often made remarks in a similar situation which they regretted.
Mr Blair has not spoken to Ms Casey, the spokeswoman said, and it is not known whether she has apologised.
Ms Casey made her comments at a conference attended by senior civil servants, chief constables and criminal justice practitioners last month.
A guest recorded the speech in which she poked fun at Home Secretary Charles Clarke.
Speaking in Stratford-upon-Avon, Ms Casey told her audience: "I suppose you can't binge drink anymore because lots of people have said you can't do it. I don't know who bloody made that up, it's nonsense."
On the tape, obtained by BBC News, she said some ministers might perform better if they "turn up in the morning pissed".
"Doing things sober is no way to get things done," she added.
But her strongest criticism was reserved for Downing Street, which she suggested was "obsessed" with conducting extensive research before formulating policies.
She apparently joked that she would "deck" Downing Street policy advisers if they kept spouting jargon at her.
At the weekend reports claimed Tony Blair had criticised Mr Clarke over a lack of action on the "respect agenda".
However, Downing Street insisted it was "absurd" to suggest Mr Blair was unhappy with Mr Clarke's handling of the issue.
Although the tone of Ms Casey's speech was light-hearted - she said the tea lady was more powerful than ministers - a number of people in the audience are reported to have walked out.
Downing Street said Mr Blair had "full confidence" in her and his "high regard for her was well known because of her record of achievements in the past".
But a spokeswoman added: "The remarks were made after a dinner and should be put into some sort of perspective.
"Lots of people have said things after dinner and when they see them in the cold light of day would regret them and no doubt she would not have wished to see them in this morning's newspapers."
A Home Office spokesman said Ms Casey was achieving a great deal in leading the campaign to tackle anti-social behaviour.
"But, like all Home Office employees, she is subject to the Civil Service Code. We are looking into her reported remarks," he added.
Harry Fletcher, assistant general secretary of the National Association of Probation Officers, said Ms Casey's remarks were "extraordinary".
They were "certainly inappropriate comments to be made by a civil servant, never mind one who is heading up the anti-social behaviour unit," he told BBC Radio 4's Today programme.
Shadow home secretary David Davis said it was "ironic" that the official appointed to report to Tony Blair on anti-social behaviour appeared to be "an advocate of binge drinking".
"Maybe this explains why alcohol-related violent attacks are up 25% and why Labour are so keen to unleash 24-hour drinking," he added.