Elon Musk testifies in his own defense during explosive opening day of defamation trial over 'pedo guy' tweet

• Elon Musk took the witness stand on the first day of his defamation trial Tuesday.
• The Tesla CEO is being sued by Vernon Unsworth, a British diver who took part in the 2018 rescue operation that freed 12 boys and a soccer coach who were trapped inside a cave in Thailand.
• Musk and Unsworth clashed at the height of that mission, during which the Tesla executive called Unsworth "pedo guy" on Twitter. Lawyers for Unsworth say that remark was widely interpreted as Musk suggesting the diver was a pedophile.
• On Tuesday, Musk told the court he had been set off by an interview Unsworth gave to CNN after the rescue, calling Unsworth's remarks "wrong and insulting." Musk testified that he chose to jab the diver on Twitter, but said: "I didn't literally mean he was a pedophile."
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LOS ANGELES - Tesla CEO Elon Musk made his first courtroom appearance as a defendant in a defamation case on Tuesday.

Musk is being sued by Vernon Unsworth, a British diver who took part in the 2018 rescue operation that freed 12 boys who were members of a soccer team and their coach after they became trapped inside a cave in Thailand.

Musk and Unsworth clashed at the height of that mission, during which the Tesla executive called Unsworth "pedo guy" on Twitter.

Lawyers for Unsworth argue the remark was widely interpreted as Musk suggesting the diver was a pedophile. Musk has denied that assertion, saying the phrase is a common expression in South Africa where he was born. Musk's lawyers unsuccessfully sought to have the case thrown out.

The trial began with jury selection on Tuesday. Several potential jurors were dismissed for various reasons, many of whom disclosed professional connections with Musk and his various companies, including SpaceX, the Boring Company, and Neuralink. The Guardian reported that one person was sent home after saying he had an upcoming job interview with SpaceX, and a woman was sent away after admitted she held "strong opinions about billionaires."

After opening statements, Musk took the witness stand, offering some insight into his thinking during his 2018 tie-up with Unsworth.

The Tesla CEO told the court he was incensed by an interview Unsworth gave to CNN after the rescue. The diver accused Musk of orchestrating a "PR stunt" when Musk sent a "mini-sub" to the rescue team while they were developing a plan to remove the boys and their coach from the Tham Luong cave in northern Thailand.

Unsworth told CNN that Musk "can stick his submarine where it hurts."

In court, Musk said Unsworth's remarks hurt him.

"So I insulted him back," Musk testified, adding: "I didn't literally mean he was a pedophile."

Lawyers challenged Musk on that assertion, pointing to a follow-up tweet in which Musk said, "Bet ya a signed dollar it's true," in reference to his original "pedo guy" tweet. Both tweets were deleted hours after he sent them in 2018.

Musk snapped back, saying he would have wagered more money if he thought it was true.

The Tesla exec faced tough questions about his intent and frame of mind around the ordeal. At one point, Unsworth's lawyers sought to determine whether Musk understood the legal consequences of publicly calling Unsworth "pedo guy," BuzzFeed News' Ryan Mac reported, citing an August 2018 tweet Musk sent in which he wondered out loud why the diver hadn't sued him yet.

Unsworth's lawyers must successfully prove that Musk's actions demonstrated negligence to the extent that they harmed Unsworth. The diver already notched a victory in earlier proceedings where the judge ruled he is not a public figure, which lowers the threshold for proving defamation.