Trial Date Set For Elon Musk's Thai Cave Rescue 'Pedo Guy' Tweet

A trial date has been set for October, with Tesla's Elon Musk facing a lawsuit brought by one of the team that helped rescue 12 boys from a Thailand cave.

A US judge says Elon Musk must face a defamation lawsuit by a British diver who said he was falsely branded a pedophile and child rapist by the chief executive of electric car company Tesla Inc.

US District Judge Stephen Wilson in Los Angeles said a reasonable jury could conclude that Musk's comments were more than merely opinions, and scheduled a trial for October 22.

The judge had on April 26 denied Musk's bid to dismiss the lawsuit brought by diver Vernon Unsworth, without explaining his reasoning.

READ MORE: British Diver Sues Elon Musk Over 'Paedophile' Tweets

Musk's lawyers did not immediately respond on Friday to requests for comment.

Rescue efforts after underway to save 13 people trapped in a cave in Thailand. Image: AAP.

Unsworth, who said in his lawsuit he shared a house in the Thailand countryside with a 40-year-old woman who owned a nail salon, was part of a team that helped rescue 12 boys and their soccer coach from a Thailand cave last July 10.He said he became a target for Musk after saying on CNN that a mini-submarine offered for the rescue by Musk from his company SpaceX, where he is also chief executive, was a "PR stunt" and that Musk could "stick his submarine where it hurts".

Thai police stand guard at the Tham Luang cave area as a rescue operation gets underway. Image: Getty

Musk later called Unsworth "pedo guy" on Twitter, a comment for which he apologised. He also urged a BuzzFeed News reporter by email to investigate Unsworth and "stop defending child rapists."

READ MORE: Elon Musk Calls Rescue Mission Cave Diver A “Pedo”

Unsworth has denied those allegations.

In seeking a dismissal, Musk's lawyers said such comments were "imaginative" or "over-the-top" insults that constituted protected opinion under the US First Amendment.

But the judge said Musk was not communicating in "heated and volatile" settings that might explain any excesses.

Unsworth is seeking at least $US75,000 ($A107,100) in compensatory damages plus punitive damages in his September 2018 lawsuit.