There have been whispers lately about Jacqui Smith, the Home Secretary. She has had a few bad weeks in which she has seemed distinctly jejune. She has looked weak and indecisive, sinking not swimming in the deadly currents of her job. So yesterday was an important test for Ms Smith when she was forced to come to the Commons to explain why she had covered up the discovery that illegal immigrants were employed in the security industry.

First, though, I bring you news on an issue of national importance. I speak, of course, of the cleavage. Ever since Ms Smith told the world of a terrorist attack while dressed for success in a singles bar, this subject has been top of the pop questions. “How’s the cleavage?” has become the standard first query whenever Ms Smith appears at the dispatch box.

Perhaps not anymore. For there was no cleavage yesterday. Indeed, I believe that Ms Smith has overcome Cleavage-gate by deploying the simple but effective camouflage of a stripey blouse. Yesterday the only thing that she revealed was her strategy for crisis management but, for me at least, it was no less impressive. The result was a bust-up of a different kind.

She was cool, calm and collected. She read her statement, hands folded in front of her like a schoolmarm (which she was). She explained, in excruciating detail, the bizarre world of the Security Industry Authority. She made it sound utterly normal that it had licensed security guards while not knowing that they were illegal immigrants. She made it sound utterly normal that since July, when she found out about this, she had not told us.

This was not because she was covering anything up. Heaven forfend! It is because she was seeking the truth. We deserve to be told the full truth and these things take time. (Indeed, at the Home Office, an eternity.) It is an ingenious defence: many a dastardly deed has been committed for truth. For instance, in their own way, the Watergate burglars were seeking truth.

“I don’t make any apologies to this House,” cried Ms Smith over Tory unrest, “for being the sort of minister whose first reaction is not what should I say about it but is what should I do about it. That is what I have done! I have taken action and when I am clear about the situation I will return and report!” Labour MPs were cardboard cutout loyalists. “Can I congratulate the Home Secretary,” they cried repeatedly. Ms Smith accepted their praise graciously and kept on extolling her own virtues.

The opposition was not impressive. Nick Clegg, the Home Affairs spokesman and leadership candidate for the Lib Dems, did not even show up. It never fails to amaze, the many ways in which the Lib Dems have lost the plot. David Davis, the Shadow Home Secretary, was lacklustre. He strutted and swaggered a bit but he never nailed the argument. His outrage sounded synthetic, his attack more automatic than heartfelt.

It was left to Michael Howard, who continues to be wonderfully creepy, to try to get an actual fact out of the Home Secretary. “When this fiasco first came to light,” he demanded, “did you tell the Prime Minister? If not, why not and if you did, did the Prime Minister remind you of his promise to abandon spin and embrace candour?”

Ms Smith bridled. “I did not tell the Prime Minister because there was not a fiasco!” she cried, her voice finally starting to squeak. “There was no fiasco, there was no blunder, there was strengthened and improved action.”

So there you have it. There was no cover-up yesterday (other than the stripey blouse, obviously). As she left the chamber, I could hear the trusty sword of truth clanking by her side as it will be, no doubt, for evermore.

Crucial dates

Late June Security Industry Authority realised that it had cleared thousands of illegal immigrants to work

July 2 It tells Home Office

July 12 Ms Smith aware that thousands of foreigners are illegally employed as security guards

July 24 The possibility of an early election is raised in the Cabinet

August 9 Memo from Ms Smith’s private secretary says that she agrees that the “lines we have are [not] good enough for . . . ministers to explain the situation”

August 20 Ms Smith told that 5,000 were employed illegally and the press office continues to advise that ministers keep quiet

August 30 Second memo repeats advice to stay silent

October 6 Mr Brown announces that he has chosen not to go to the country in the autumn

November 11 Reports that thousands of immigrants have been wrongly licensed to work in high-profile security jobs

November 12 Reporters told that the reason for the previous news blackout was not to compromise immigration raids

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