The government has defended spending nearly £130,000 on legal advice about Boris Johnson's Partygate scandal.
Critics have questioned why the public is footing the bill for a report by lawyer Lord Pannick into an inquiry by the privileges committee into whether the ex PM misled Parliament.
Downing Street commissioned the legal advice from the crossbench peer and published it on the Government website, revealing that the QC had ruled the committee was adopting an "unfair procedure" and "fundamentally flawed" approach.
Lord Pannick worked for four months after being awarded the contract.
The committee is investigating whether Mr Johnson misled the Commons in his statements about the Partygate scandal, and whether this obstructed the functioning of Parliament.
It will also weigh up how serious the contempt was, if it decides Mr Johnson was guilty of wrongdoing,
Green Party MP Caroline Lucas had questioned why the spending was authorised.
In a response from Cabinet Office minister Edward Argar, released quietly while Parliament is in recess for party conferences, the government said it was funded because the probe is related to the former PM “making statements at the dispatch box on behalf of the government as a minister”.
He also said that there was no ministerial direction - something that is issued if civil servants aren't convinced a move represents value for money.
Following the response, Ms Lucas told The Guardian : “This payment for legal advice is a blatant and outrageous use of public money to protect an individual who is being investigated for his personal conduct in the house."
She said that the investigation is into his "personal and individual decision to lie", adding: "Dressing this up as government business simply does not wash.”
Labour deputy leader Angela Rayner said Mr Johnson “spent months hiding the truth, dodging scrutiny and deceiving the public".
She hit out at the Liz Truss government, adding: "But rather than holding him responsible for his indefensible behaviour, Liz Truss's Tories are yet again backing him to the hilt, allowing him to bend the rules so voters have to pick up his legal bills.”
The seven member committee, chaired by Labour's Harriet Harman, is set to resume when the Commons returns next month.
It is believed that Tory backbencher Charles Walker could fill the remaining vacant spot on the committee.
Mr Johnson is almost certain to be called, but he could decide not to attend, The Guardian reports.
In a most extreme case he could be suspended or expelled, sparking a byelection in his Uxbridge and South Ruislip constituency.
Mr Agur's response on the Parliament website states: "As the Privileges Committee inquiry relates to the conduct of the now former Prime Minister making statements at the despatch box on behalf of the Government as a Minister, the Government is supporting his response to Parliament, as with any Minister, and has instructed legal support. No Ministerial Direction was issued."