India’s IT outsourcing giant Tata Consultancy Services Ltd. needs to offer a good explanation for why engineers hired at its American outposts are 13 times as likely to be fired if they’re not South Asian. The company is set to go on trial Monday in California over racial discrimination claims by American workers who lost their jobs at TCS offices in the U.S. because they hadn’t been assigned to any of its clients. Mumbai-based TCS denies any unlawful bias in its U.S. operations and says in court filings that the Caucasian American leading the lawsuit was removed from one of its projects and ultimately terminated over performance concerns. Our success is based on our ability to provide the best talent available, both in the US and globally, based purely on the individual’s specialized experience, skills and fit for each client’s specific needs, a company spokesman said. The plaintiffs allege TCS has engaged in a systematic pattern and practice of discrimination by favoring Indian ex-pats and visa-ready workers from India for U.S. positions. That has resulted in a workforce that’s almost 80 percent South Asian, far greater than the 12 percent representation of South Asians in the U.S. IT workforce, according to the complaint. U.S. District Judge Yvonne Gonzalez Rogers in Oakland scaled back the case to focus only on allegations about bias in firings, after concluding there was insufficient evidence to back up the claim that TCS discriminated against non-South Asian job applicants. The trial is slated to take about 18 days.