The Home Secretary has been accused of misleading the House of Commons by a Labour MP, in a row over identity cards.
Birmingham MP Lynne Jones (Lab Selly Oak) accused Charles Clarke of misleading MPs during a tense vote on ID cards last month, in which Labour rebels halved the
Government's majority from 64 to 31. The allegation has been denied by the Home Office.
Misleading the Commons is one of the most serious offences any MP can be accused of.
It is considered to be contempt of Parliament, which can theoretically lead to an MP being suspended or even expelled.
In practice, an MP found to have misled colleagues would probably be forced to make a public confession, and Dr Jones has written to Mr Clarke demanding he apologise.
The row follows a crunch Commons vote on February 13, when MPs backed Government proposals to make it compulsory to obtain an ID card when applying for a passport. Dr Jones was one of 20 Labour rebels who voted against the Government.
In the debate before the vote, she criticised plans to include up to 13 biometric elements, such as fingerprints and iris scans, on a national computer database.
She asked Mr Clarke: "Which other countries propose to have 13 sets of biometric data on a centrally held database?"
The Home Secretary told her: "A number of countries, including the United States of America, is the answer."
However, the MP said she received a different answer when she asked the House of Commons Library to verify his answer. She said staff in the library asked the Home Office where Mr Clarke had obtained his information.
But Home Office officials replied: "We have no specific information as to when other countries will move to using 13 biometrics."
In a letter to the Home Office, Dr Jones said: "I suggest it would be appropriate for the Home Secretary to apologise for misleading the House."
A Home Office spokeswoman said: "The use of multiple biometrics has been accepted in principle by the International Civil Aviation Organisation (ICAO), and by the 188 ICAO contracting states."
The Commons vote means everyone applying for a British passport from 2008 will have to obtain an identity card too. ..SUPL: