A pro-Corbyn blogger on Tuesday launched an appeal against a defamation suit brought against him by Jewish Countdown star Rachel Riley after he described her as a “serial abuser”.
 
A judge ruled in January that Mr Sivier “no prospect” of mounting a successful defence in a full libel trial, but the blogger is now arguing for a review of the decision and for the case to be reheard at the High Court, possibly by a jury.
 
Mr Sivier accused the TV presenter in 2019 of having engaged in and encouraged a campaign of online harassment against a 16-year-old Twitter user sympathetic to Jeremy Corbyn.
 
He said Ms Riley was a “serial abuser” and that she had “cold-shouldered" the teen, identified only as Rose, leading to her receiving death threats.
 
In the course of a two-year legal battle, he defended the claim by arguing it was “substantially true”.
 
But Mrs Justice Collins Rice struck out Mr Sivier's defence in January, saying: “If it is not even arguably true that Ms Riley engaged in or encouraged and supported a campaign of online abuse and harassment of Rose, I do not see that opinions based on the fact of her having done so can themselves survive to be defended.
 
“Mr Sivier’s article has been ruled to have nailed its colours to the mast of a factual allegation and a series of consequential opinions.” 
 
David Mitchell, acting for Mr Sivier, argued at the appeal hearing on Tuesday: “This is a distinctly, inherently fact-sensitive exercise which is not suitable for summary determination.
 
“It would be perfectly possible for each of us to read the Tweets in different ways.
 
“We will show on the part of the claimant a lack of willingness to leave the child alone.”
 
John Stables, acting for Ms Riley, said: “It’s my client’s conduct on Twitter which is in question in this case.
 
“My client did not encourage anybody to do anything.
 
“The exchanges were respectful and civil, this is a misplaced argument.”
 
Earlier this month Ms Riley announced that she and husband Pasha Kovalev were expecting their second child together.
 
The hearing continues.