Who do you believe, then - HM Attorney General or a self-confessed illegal immigrant?

I refer, of course, to the Mail on Sunday interview with Loloahi Tapui, in which the Tongan says she did not show Lady Scotland a passport when she was taken on as a housekeeper.

In response, Lady Scotland insists that she was shown "all relevant documents - a P45, National Insurance details, a marriage certificate, a letter from the Home Office, references and a passport - by Ms Tapui during her job interviews".

Her reference to "interviews" may be significant: the two women may have been referring to different occasions. But at one level it does not matter whether Lady Scotland saw a passport or not.

That is because appendix one to the code of practice issued under the Immigration, Asylum and Nationality Act 2006 makes says that only one of the documents in List A need be produced.

Top of the list is a passport indicating that the holder is a British citizen. But the last item on the list is a letter from the Home Office indicating that the holder is allowed to stay indefinitely in the UK, provided there is also a document, such as a P45, giving the holder's National Insurance number.

If only Lady Scotland had taken copies of the Home Office letter and the P45, she would have been in the clear.

If, however, there is reliable evidence that Ms Tapui's account was accurate, it would make things very difficult for the Attorney General. She could not survive a finding that she had misled the public, however inadvertently.