"Why was Bauer Media, with all of its worldwide resources, unable to identify a single person anywhere in the world to whom the supposed lie had been said - a friend, a former friend, a colleague, an agent, a producer, a publicist, a member of the public, anyone?" he said.
"This proceeding has been reported in the press every day over the past three weeks. Why hasn't someone come out of the woodwork to corroborate this allegation that Rebel Wilson is a liar?
"The reason why they came up with nothing, of course, is obvious. Rebel Wilson has not lied."
Dr Collins said Wilson took legal action to "stand up to a bully".
"She doesn't say that these articles are the worst thing that have ever happened in her life and that you should all feel sorry for her. She says that she is not a serial liar, as alleged by this defendant, and she seeks your verdict to tell that to the world, to tell the world that what this defendant did to her was wrong," he said.
"Rebel Wilson came here to stand up to a bully. Her claim is not about money, it is about restoring her reputation."
