Tesla faces a lawsuit for racial discrimination at its California production plant. It’s at least the third filed this year by black workers who say they were addressed using racial slurs and that the company ignored their complaints. But Monday’s lawsuit, filed by former Tesla employee Marcus Vaughn, is the first to bring those claims on behalf of a large class of black workers at the automaker’s Fremont, Calif., factory. Tesla did not respond to a request for comment. The company is also facing lawsuits accusing it of discrimination against gay and older workers. It has denied those claims. Vaughn in the lawsuit says he was routinely called the “n-word” by supervisors and coworkers after he began working at the factory in April. He says he complained in writing to human resources officials, but the company never investigated his claims.