A Tesla whistleblower who has fought Elon Musk and his company through the courts for years has won the latest round of a long-running legal battle.

Engineer Cristina Balan lost her job after she raised a safety concern in 2014 about a design flaw which could affect the cars' braking.

Her defamation claim against the firm seemed to have run out of road when a judge confirmed an arbitration decision dismissing her case - but a panel of appeal judges in California has reversed this decision in her favour.

She told BBC News she now wants to face Elon Musk and Tesla in open court.

Tesla has not responded to a request for comment.

Ms Balan said she believes the case will now in effect go back to square one, and new proceedings can be launched.

"We are hoping we will start a new lawsuit and we will have the chance to take on Elon Musk in front of a jury and judge," she said.

The engineer was once so prominent at Tesla that her initials were engraved on the batteries inside Model S vehicles.

In an interview with BBC News last year, she said she is determined to prove her innocence for the sake of her son.

She also revealed she was in remission from stage-3B breast cancer, and her biggest worry was she may not live to see her final day in court.

Ms Balan claimed she was worried the carpets were curling underneath some pedals in Tesla models, creating a safety hazard.

She said managers rebuffed her concerns, became hostile, and she lost her job.

She then won a wrongful dismissal case - but this turned out to be the start of a long journey through the courts.

Ms Balan was publicly accused by Tesla of using its resources for a "secret project" - accusations which amount to embezzlement, a crime under US law.

She has consistently denied the accusation, and decided to bring a defamation case against the firm in 2019.

"I want to clear my name," she told BBC News last year.

"I wish Elon Musk had the decency to apologise."

A court then decided Ms Balan's case should be subject to arbitration per a contract she signed while working for Tesla.

The arbitrator found in favour of the firm and Musk, dismissing her claims, due to California's statute of limitations - meaning too much time had passed since the alleged defamatory statements were made.

Tesla brought the case back to a district court in California to have the decision confirmed.

However, Ms Balan appealed this decision, and judges from the US Court of Appeals for the Ninth Circuit found in her favour - in effect deciding the California court did not have the jurisdiction to make its judgement.

They have ordered for the confirmation of the arbitration award to be cancelled, and for the district court to dismiss the action due to its lack of jurisdiction. (BBC)

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