Tesla chief Elon Musk is set to go to trial Tuesday in a defamation lawsuit over his infamous Twitter post calling a British cave explorer a “pedo guy.”

A jury in Los Angeles will decide whether Musk will have to pay for lobbing the insult at Vernon Unsworth, who helped rescue a group of boys trapped in a network of caves in Thailand in July 2018.

Musk apologized for the comment and deleted the tweet. But Unsworth sued the billionaire investor for damages, claiming his reputation was damaged by being baselessly branded a pedophile.

Musk plans to testify in his own defense during the trial, which is slated to last about five days. US District Judge Stephen Wilson plans to ask potential jurors whether they have strong opinions on billionaires or people who live in Thailand.

Unsworth’s case got some help last month when the judge ruled that he was not a public figure. He only has to prove Musk was negligent rather than the higher standard of “actual malice.”

The “pedo guy” post came in an irate string of tweets Musk posted after Unsworth criticized his offer to help with the rescue mission by sending a mini-submarine built by his rocket firm SpaceX.

Musk lawyer Alex Spiro has accused Unsworth of wanting to “milk his 15 minutes of fame.” Musk has said in court documents that “pedo guy” was a common insult “synonymous with ‘creepy old man'” when he grew up in South Africa.

“I did not intend to accuse Mr. Unsworth of engaging in acts of pedophilia,” he said in a Sept. 16 filing. “I meant to insult him back by expressing my opinion that he seemed like a creepy old man.”

Musk has a history of getting into hot water on Twitter. He agreed to have his statements about Tesla’s finances vetted by legal counsel in an April deal with the Securities and Exchange Commission after he tweeted that he planned to take Tesla private at $420 a share.

With Post wires