Brighton Pavilion MP Caroline Lucas broke official rules by offering a personal tour of Parliament to raise funds towards her re-election campaign.
The Green MP said that she had breached the rules inadvertently and apologised to the Parliamentary Standards Commissioner Kathryn Stone.
The finding came after a complaint by Brighton-born Conservative MP Michael Fabricant, who represents Lichfield in Staffordshire.
The commissioner said: “I investigated the allegation that the member had breached … the Code of Conduct for Members by offering a guided tour of Parliament in an auction to raise funds for a political party.
“During my inquiry, I established that the member had agreed to sell through a crowdfunder site a personal tour of Parliament and a signed order paper to raise funds as part of her re-election campaign.
“On considering the sale of the signed copy of the order paper, and after seeking advice from the House, I concluded this was not a breach of the rules.
“However, my investigation established that the member had, on her return to Parliament after the election, hosted a tour of Parliament, which had been paid for via an online fundraising campaign.
“I found that in doing so the member had acted in breach of the rules.
“The member acknowledged their breach, apologised and undertook not to repeat it.”
Mr Fabricant, who complained after reading on the Mail Online website: “A £150 donation gets you a guided tour of the Commons while £250 secures lunch with her.”
He said: “This article says that this is a personal guided tour if she is re-elected.
“I believe it inappropriate for her to be touting for donations using the facilities of the House of Commons as an inducement.
“This is also an unfair advantage over other election candidates.”
After the commissioner’s verdict, Caroline Lucas said: “I have today written to the Parliamentary Standards Commissioner to accept the outcome of her investigation and apologise for an inadvertent breach of the code of conduct.
“In order to raise funds for my local party in the recent general election campaign, I made an offer on a crowdfunding site of a personal tour of those areas of Parliament which are special to me.
“When I did so, I did not believe I was breaking parliamentary rules, which I had interpreted to mean that what was prohibited was offering something that was otherwise ‘freely available’.
“I did not believe such a personal tour was ‘freely available’.
“However, the commissioner has ruled that this was a breach of the code of conduct and I accept her decision.
“I would like to apologise for this completely unintentional breach of the rules.
“The Green Party has returned the money to the supporter who made the donation.”
The report by the Parliamentary Standards Commissioner can be found here.
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