Former Conservative Party co-treasurer Peter Cruddas has accused David Cameron of unfairly treating him as an "outcast" following accusations he had offered to sell access to the prime minister.
Cruddas won £180,000 damages today in his High Court libel action over a Sunday Times allegation about charging £250,000 to meet David Cameron.
The 59-year-old businessman brought the claim against Times Newspapers Ltd and two members of the newspaper's Insight team over three articles which appeared in March 2012.
He complained they meant that, in return for cash donations to the Conservative Party, he corruptly offered for sale the opportunity to influence Government policy and gain unfair advantage through secret meetings with the prime minister and other senior ministers.
During the litigation, the Court of Appeal ruled that "corruptly" meant "inappropriate, unacceptable and wrong and gave rise to an impression of impropriety".
He also said they meant he made the offer even though he knew the money offered for meetings was to come, in breach of the ban under UK electoral law, from Middle Eastern investors in a Liechtenstein fund and was happy that the foreign donors should use deceptive devices to conceal the true source of the donation.
The newspaper, which also has to make a £500,000 costs payment by mid-August, had pleaded justification.
Cruddas said later: "The dark cloud that has hung over me and my family since the Sunday Times published its malicious lies about me 16 months ago has finally been lifted and justice has been done.
"My world was turned upside-down when that article was published. I remember vividly having to walk into my offices the day after the article was published and face 500 of my staff, many of whom had a clip of the Sunday Times interview on their video screens. It was humiliating.
"I was also embarrassed to accept invites to events which meant that my charities suffered. The Conservative Party cut me off within two hours of the story breaking and did not want to hear my side of the story.
"I was constructively dismissed from my role as party treasurer and made to feel like an outcast as the Prime Minister and the party lined up to criticise me on television and radio. This hurt me immensely and further damaged my reputation.
"Since the article was published I have kept a dignified silence and let the legal process do the talking for me. Perhaps the Sunday Times under-estimated me and thought I would quietly disappear but I knew all along that I was telling the truth and that the story was malicious, so I was prepared to fight all the way.
"I hope my victory shows that this type of journalism employed by the Sunday Times and its journalists Heidi Blake and Jonathan Calvert is totally unacceptable, particularly post Leveson."
He added: "Today is a good day for me. I am delighted that my good name has been restored. My family, friends and legal team have shown me huge support throughout, which has kept me going, and I sincerely thank them."
Former Conservative treasurer and major donor Lord Ashcroft said the party "needs to learn major lessons from this debacle".
Writing on the ConservativeHome website, Lord Ashcroft said: "Mr Cruddas quite rightly alerted the party's hierarchy to events and must have hoped for, even expected, its full support. Yet, despite contradicting the paper's version of events, he was forced to resign within hours and was ostracised by senior party figures (except predictably Michael Gove) over the next weeks and months. He has had no Party invitations since his resignation."
Lord Ashcroft said: "I hope that Mr Cameron will now offer Mr Cruddas an apology for his criticism of him, and for forcing him to step down as treasurer with such haste when Mr Cruddas was fulfilling his unpaid role well and effectively. That would be the right thing to do.
"Surely the instincts of our party should always be to stand by one of its own until it has been proved that an individual has acted illegally or improperly even if it may be politically appropriate in certain circumstances to suspend someone pending an outcome."
Conservative chairman Grant Shapps repeatedly refused to apologise on behalf of the party for the way Mr Cruddas was treated.
He told reporters: "I think Peter Cruddas did exactly the right thing. He has pursued this through the courts and got the outcome that he wanted, the right outcome as well, and good luck to him.
"He has got the right to that and it's good that he did."
Pressed on whether there was a need for the Tories and Mr Cameron to say sorry, Mr Shapps said: "I don't really think it's a question of that, I think it's a question of congratulating Peter Cruddas for managing to pursue this and get the right outcome."