Ms Riley, 35, the Channel 4 show’s numbers expert, has taken action against Laura Murray over a tweet she posted more than two years ago.
The High Court heard how the two women tweeted after Mr Corbyn, then a Labor leader, was hit with an egg while visiting a mosque in March 2019.
Ms Riley had posted a screenshot of a January 2019 tweet from Guardian columnist Owen Jones about an attack on former UK National Party leader Nick Griffin, which read: ‘I think a good Life advice is, if you don’t want eggs thrown at you, don’t be a Nazi.”
She added, “Good advice,” along with emojis of a red rose and an egg.
Ms Murray later tweeted: “Today Jeremy Corbyn went to his local mosque for Visit My Mosque Day and was attacked by a Brexiteer. Rachel Riley tweets that Corbyn deserves to be roughed up attacked because he is a Nazi. This woman is as dangerous as she is stupid. No one should engage with her. Ever.
Ms Riley said she was sarcastic in her tweet, did not call Mr Corbyn a Nazi and told the judge that Ms Murray’s tweet had seriously damaged his reputation.
Ms Murray was stakeholder manager in Mr Corbyn’s office when he was leader of the Labor Party, and later was party complaints manager, before moving into teaching. She maintained that what she tweeted was true and reflected her honest opinions. Judge Nicklin overseeing the High Court case in London in May said Ms Murray’s tweet was defamatory.
Yesterday he ruled that Ms Riley had demonstrated that Ms Murray’s tweet had seriously damaged her reputation.
The judge rejected Ms Murray’s argument that denying her defense would constitute an unjustifiable interference with her right to free speech.
Ms Riley, who is on maternity leave from Countdown after giving birth in November, told the judge she was Jewish and spoke out against anti-Semitism and believed the Corbyn-led Labor Party ‘fosters anti-Semitism’.
She wrote: “I am extremely happy to have won my libel case against Laura Murray, former Complaints Officer for the Labor Party. It has been a very exhausting process and I am relieved to finally have a vindication.”