A man has won £40,000 damages from a former UKIP official over a tweet that falsely accused him of child grooming.
Zahir Monir, a businessman from Rotherham, brought a High Court libel case against Steve Wood, the former chairman of UKIP's Bristol branch, who stood in the May 2015 general election.
Mr Justice Nicklin said the allegation had badly affected Mr Monir's life.
In his ruling, he said: "Mr Monir is completely innocent. He has been seriously libelled."
The tweet featured a photo of Mr Monir, 39, and another person standing either side of Labour MP Sarah Champion, with the statement: "Sarah Champion labour candidate for Rotherham stood with 2 suspended child grooming taxi drivers DO NOT VOTE LABOUR".
The judge said: "He has been forced to fight a libel claim all the way through to trial with every single conceivable point being taken against him."
Mr Wood, a former police officer who now runs a bailiff firm, had adopted a "mean-spirited stance" in refusing to apologise and withdraw the allegation, the judge added.
Had the allegation been published in a national newspaper, he said he would have awarded damages of £250,000.
The tweet, published on Bristol UKIP's official Twitter account on 4 May, three days before the election, was written and posted by John Langley - the branch's vice-chairman at the time.
It was published to @BristolUKIP's 547 followers, retweeted at least 17 times, liked at least eight times, published on the official Bristol UKIP webpage and republished on Facebook.
Although Mr Langley wrote the tweet, Mr Justice Nicklin found he was "quite clearly acting as the agent of Mr Wood".
Mr Monir's solicitor Jeremy Clarke-Williams said the judgment was "extremely important" and would have to be considered carefully by those who have social media accounts that others operate on their behalf.