Boris Johnson has made eleventh-hour representations to the privileges committee before it publishes a report which is expected to find that he deliberately misled parliament.
A spokesman for the inquiry said it was "dealing with" further submissions received from the former prime minister at 11.57pm on Monday.
It came as the panel of MPs examining claims that Mr Johnson lied to parliament over "partygate" met to conclude its investigation.
Their report was expected to be published as early as Wednesday after Mr Johnson quit as an MP, having received an advanced copy of its findings.
In an explosive 1,000-word statement he accused the committee, chaired by Labour's Harriet Harman but with a Conservative majority, of "bias" and likened it to a "kangaroo court".
It has been suggested that - before his shock resignation - the panel had been discussing a 20-day suspension, triggering a recall petition and potential by-election.
He cannot be suspended now he has resigned, but he could be refused a parliamentary pass offered to former MPs, a sanction imposed on former speaker John Bercow after a bullying report.
Despite the findings expected to be damaging, Mr Johnson has insisted "I'll be back" - a reference to Arnold Schwarzenegger's Terminator.