NEW DELHI— Google Inc. and Facebook Inc. are set to begin trial here Tuesday to face charges that they didn't censor objectionable content from their sites, putting on stark display the legal risks for Internet companies chasing growth in India.

The case is the highest-stakes example yet of the controversy in India over what role Internet companies should have in policing content on the Web. If convicted, executives from the companies could face jail time and the companies could face fines, lawyers following the case said.

The trial comes as Google and Facebook see India as an important growth market. Facebook, which faces heavy restrictions in China, said in a recent filing for its planned U.S. initial public offering that India is among its most significant sources of growth. The company said it had 46 million monthly active users in India at the end of last year, up 132% from a year earlier.

The opportunity in coming years looks promising, because less than 10% of India's population of 1.2 billion is online, according to the Internet and Mobile Association of India trade group. A Google executive said last year that the company expects India's Web user base to grow by 200 million people to reach at least 300 million by 2014, largely driven by increased Internet use on mobile phones.

India hasn't pursued website-blocking as aggressively as China, Iran or Syria have. But New Delhi has regulated a range of content, including political satire and material that could offend religious groups. Under regulations India put in place last year, Internet companies are supposed to remove within 36 hours of being notified material that falls into a range of categories—for example, anything "ethnically objectionable," "grossly harmful," "defamatory" or "blasphemous."