Two of the 'Partygate' questionnaires sent out by the Metropolitan Police were never returned according to documents seen by ITV News.
In a letter to the Liberal Democrat Chief Whip, Wendy Chamberlain, the Met said that out of 204 questionnaires that were issued, two were not returned.
However, the force suggested that has not led to anyone escaping a fine.
The police did not reveal who the individuals were that failed to return the questionnaires.
Deputy Assistant Commissioner Jane Connors wrote that; "The two individuals sent the questionnaires were still assessed against all the available evidence and, while I cannot give individual details, I can confirm that a ‘non-response’ certainly did not prevent us from referring for an FPN to be issued if it was appropriate to do so.
"As the Acting Commissioner said at the London Assembly’s Police and Crime Committee, failure to return a questionnaire spurred the team on rather than impeded them."
Twenty-eight people were fined more than once including at least one person being fined five times.
Wendy Chamberlain has also asked the Met to clarify whether or not anyone who did return a questionnaire had filled it in properly.
She said “It’s important that we find out more about the two individuals who failed to return a questionnaire to the police, whether they were Conservative ministers or senior officials, and if one or both then received a fine.
"We also need urgent clarity over claims that some individuals failed to properly fill in their questionnaires."
Whilst this is not the most serious revelation of the whole 'Partygate' saga, it does make you wonder whether there are people working in Downing Street or the Cabinet Office who don't think they need to bother replying to official police enquiries.
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