Uber

A US judge has warned Uber that its self-driving car program could be halted by a lawsuit it's embroiled in.

Uber is battling it out with Waymo, the self-driving car unit of Google's parent company, Alphabet, and the ride-hailing company's key witness said Thursday that he intends to plead the Fifth and not testify in the case, according to Bloomberg.

That witness, Anthony Levandowski -- who is Uber's head of autonomous vehicles -- said that testifying could open him up to criminal prosecution. The US Constitution's Fifth Amendment protects individuals against self-incrimination.

Judge William Alsup replied that testimony or not, Uber could still be slapped with preliminary injunction.

"If you think for a moment that I'm going to stay my hand because your guy is taking the Fifth Amendment and not issue a preliminary injunction to shut down what happened here, you're wrong," Alsup said in a closed hearing on Wednesday, according to Bloomberg.

Uber has self-driving car pilots in Pennsylvania, Arizona and California. An injunction against the company could affect all three of these projects.

Waymo filed its suit against Uber in February, and the original complaint read like a spy novel.

Levandowski, a former Google employee, helped develop the company's lidar technology, a key component for self-driving cars that uses lasers to detect objects in a car's environment. Before leaving Google to found Otto, a self-driving trucking company, Levandowski allegedly downloaded 14,000 "highly confidential" files to a hard drive.

The suit says San Francisco-based Uber benefited from the information after it bought Otto last year. Waymo said it learned of the alleged theft after a supplier accidentally emailed a Waymo employee a diagram of Uber's lidar dashboard.

The lawsuit, being heard in the District Court for the Northern District of California, also complicates the already difficult relationship between the two companies. GV, Alphabet's venture capital arm, invested in Uber in 2013. It was one of the firm's most high-profile deals.

As high profile as the legal battle is, Uber hopes parts of it will take place outside of public view. The company last week filed a motion to request that the disputes around trade secrets be resolved in private arbitration instead of a public court. The hearing to decide this matter is scheduled for April 27.

The hearing for Alsup to decide whether to impose the preliminary injunction against Uber is set for May 3.

During the closed hearing on Wednesday, Uber lawyer Arturo Gonzalez told Alsup that "we're going to demonstrate to you that we are not using any of these things that they say he may have taken," according to Bloomberg.

Uber said it plans to release its first public response and to lay out its case next week.

"We are very confident that Waymo's claims against Uber are baseless and that Anthony Levandowski has not used any files from Google in his work with Otto or Uber," said Angela Padilla, associate general counsel at Uber.

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