Mr Abdelkarim is then heard approaching and asking the man if he minds being filmed, telling the man he will "knock it [the camera] off" if he does not wish to be filmed.
But the subject replies: "I have nothing to hide." Mr Gold alleged that Mr Abdelkarim then launched himself at him. "He was growling and my cheek was pinned between his teeth, I felt like he was trying to bite my ear off. I could feel his breath and him moving towards my ear. My cheek was clamped, vice-like, in his teeth."
The defence argued that it was Mr Abdelkarim who had been first punched by Mr Gold, and then pinned in a bear hug, before resorting to biting Mr Gold in order to free himself.
Srikantharajah Nereshraaj, defending, said the pro-Israel activists had been present to "disrupt, antagonise and provoke reactions" at what he described as a "Palestinian cultural event."
Mr Abdelkarim said the Israel campaigners had apparently ignored his requests not to take pictures of his two young children. Israeli film student Roy Goldman, who was called as a witness, agreed that he had been filming and taking pictures at the event.
Mr Abdelkarim told the court he was "not a political person" and had come to the event with his family for food and face-painting. "I did not want my children appearing in any footage at all," he said. He had noticed Mr Gold filming. "I could see they [his children] would appear in the background."
Both men were originally charged with assault, but charges against Mr Gold were dropped. Three witnesses from the pro-Israel campaign outside the university gave evidence, as did others attending the event.
District Judge James Henderson said political points of view of the witnesses on both sides had affected "what they saw and how they interpreted it." But, he said, although there were inconsistencies in the accounts given by prosecution witnesses Mr Goldman, Stand With Us organiser Gili Brenner, and Anthony Coren, he had "no reason to disbelieve them."
But Kuwait-born Mr Abdelkarim, 44, a father-of-two and part-time university lecturer, was also "consistent and believable", the judge said. "A man out with his children and paediatrician wife is an unlikely man out for trouble. But even a family man can be provoked and lose their temper and lash out".
Dismissing the charge, he said: "I cannot be sure that Mr Abdelkarim was not acting in self-defence. The prosecution has not proved that".
Stand With Us director Joy Wolfe said: "Clearly this is a disappointing outcome, but it is not the first time and won't be the last that a court has been unable to convict 'beyond reasonable doubt.'
"Not surprisingly the PSC and Jews for Justice for Palestinians were on hand to gloat, but Dean Gold and his witnesses can walk away with their heads held high, knowing the reality of what happened to him."
