The Liberal Democrats suspended a staff member after being accused of falsifying an email to nullify negative news.
The unidentified official allegedly faked the email to prove that the Liberal Democrats had responded to a request for comment from the OpenDemocracy website.
Liberal Democrat lawyers accused OpenDemocracy of "irresponsible" behavior that "intended to disparage our client" after the site published an article about the party selling data for the Stay campaign in 2016.
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Leading commercial law firm Goodman Derrick said OpenDemocracy did not include comments from the Liberal Democrats and demanded that the part be changed or removed.
To prove that the party had responded, the lawyers provided an email from the staff member whom the official claimed was the Liberal Democratic Party's response to OpenDemocracy.
The email was dated November 12th.
OpenDemocracy did not ask for comments on the story until November 13.
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The "answer" also had a subject that did not address the story in question.
When presented with this information, along with more evidence that OpenDemocracy had not received a comment from the Liberal Democrats, the party initially threatened the site with legal action.
In an email sent at 10.57 on November 29, viewed by Sky News, Goodman Derrick told OpenDemocracy that Liberal Democrats "may wish to request an urgent injunction to prevent the publication of any false allegations of forgery and fraud."
Just over three hours later, the party changed its history.
A letter from Goodman Derrick to OpenDemocracy, emailed at 2:17 pm on November 29, admitted that the team member's email was "incorrect".
The letter said Liberal Democrats "suspended the official involved in the production of this e-mail and launched an urgent investigation into the matter."
He added: "Neither contact with our clients (the Liberal Democrats) nor this company had reason to believe that the email was not genuine."
Mary Fitzgerald, editor in chief of OpenDemocracy, told Sky News that this was "shocking behavior" that she "did not expect" from the Lib Dems.
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"What do you say about Lib Dems' respect for fact-checking, accuracy and freedom of the press?" Fitzgerald said.
"The party urgently needs to clarify who sanctioned this aggressive and expensive lawsuit, which repeatedly made false allegations and included a badly falsified document."
The original OpenDemocracy story of former independent political correspondent James Cusick revealed "new evidence" that liberal Democrats sold voter data for the Stay campaign.
The story, published Nov. 13, says the UK data controller has documents showing that the party made a £ 100,000 deal with the Remain campaign to provide data during the EU referendum in 2016.
A Liberal Democratic Party spokesman told Sky News: "Liberal Democrats refute the allegations made in the November 13 OpenDemocracy article.
"However, we were told that the information OpenDemocracy subsequently received from Liberal Democrats was incorrect.
"We have suspended a member of the team involved and are following the due process."
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