(Bloomberg) –Elon Musk called a TV interview a British caver gave an “unprovoked” attack from someone he didn’t know. He responded in a tweet, labeling the man “pedo guy.”
Vernon Unsworth, the caver, didn’t take the insult lightly and sued the Tesla Inc. chief executive officer for defamation.

Now, the two are squaring off in a Los Angeles courtroom, attempting to convince a jury of five women and three men to see their side of the case. Musk is the first witness, called by Unsworth’s lawyer L. Lin Wood.

“I thought he was just some random, creepy guy that the media interviewed,” Musk said of Unsworth. “So, I insulted him back.”

The feud between the two began when the caver criticized Musk’s effort to help rescue members of a Thai soccer team from a flooded cave in 2018 — an event that drew the attention of worldwide media. Musk and engineers at his companies prepared a mini submarine, built with rocket parts, to help with the rescue efforts. The kids were saved without the sub.

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Unsworth, who helped in the rescue, ridiculed the high-profile effort from the celebrity CEO. He told CNN that Musk could “stick his submarine where it hurts,” and that it was just a PR stunt with no chance of working.

Those comments were wrong and insulting, Musk told the jury. So, he fired back with the “pedo guy” tweet. But, the insult wasn’t meant to be taken literally, Musk said.

“I knew he didn’t literally mean to sodomize me with a submarine, just as I didn’t literally mean he was a pedophile,” Musk told the jury.

Musk, who is also chief executive of Space Exploration Technologies Corp., was calm and polite most of the time on the witness stand. He avoided reporters as he arrived at the courthouse in downtown Los Angeles just after noon local time.

As a scrum of journalists waited outside the courthouse, Musk’s team used a decoy car to divert attention. While a red Tesla pulled up front, Musk and his entourage of security guards emerged from around the corner and quickly entered the building. He also avoided reporters on the way out.

The man with 29.8 million followers on Twitter and visions of sending people to Mars also played down his degree of influence.

Rage, rage against the dying of the light pic.twitter.com/aGRw4VowAQ

— Elon Musk (@elonmusk) September 28, 2019

“I’m not sure to the degree I’m influential,” Musk said. “I tried my best to make the U.S. government take climate change seriously,” but, he said, the Trump administration pulled out of the Paris climate accord anyway. He also told the jury Tesla doesn’t have much of a public relations department.

Musk, who had apologized to Unsworth on Twitter, did so again in court.

“I’ll say it again,” he said. “I apologize to Mr. Unsworth.”

The only time during about four hours of questioning that Musk came close to losing his cool was when he sparred with Wood over a demand letter he received from the lawyer.

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Musk viewed the correspondence as a “shakedown letter from a shakedown lawyer” and told Wood “I think you’re looking for a significant payday.”

That sparked a clash between the lawyer and the witness until Judge Stephen Wilson told them to “cut the repartee.”

Musk returns to the stand on Wednesday for further questioning.

Unsworth, who sat with attorneys in the courtroom, is represented by Wood. The Atlanta attorney is best known for representing Richard Jewell, the security guard falsely accused of being connected to the Centennial Olympic Park bombing during the 1996 Summer Olympics.

Taylor Wilson, who also represents Unsworth, said in his opening statement that Musk’s tweets caused the U.K. resident tremendous shame. Unsworth, an experienced caver who is knowledgeable about the site where the boys were trapped, helped connect the Thai government to British divers who helped their rescue, the lawyer said.

“Mr. Unsworth did the only thing he could,” Wilson said. He filed a lawsuit against Musk “for accusing him of being a pedophile in what should have been the proudest moment of his life.”

According to Musk’s lawyer, Alex Spiro, there’s no evidence that Unsworth suffered any damages. On the contrary, Spiro told the jurors, Unsworth became a celebrity notwithstanding Musk’s tweets and was honored by the Queen of England and the King of Thailand for his part in the rescue.

“These are joking, talking tweets in a fight between men,” Spiro said. “It was a joking, deleted, apologized-for, responsive tweet. A JDART.”

The case is Unsworth v. Musk, 18-cv-08048, U.S. District Court, Central District of California (Los Angeles).