Prager University, a nonprofit that produces short, educational videos from conservative perspectives, is suing YouTube and its parent company, Google, claiming the tech giant is illegally censoring some of its content as part of a wider effort to silence conservative voices.

A lawsuit filed Monday evening in federal court in San Francisco says YouTube’s more than 30 million visitors a day make the site so elemental to free speech in the digital age that it should be treated as a public forum. The suit argues the site must use the “laws governing free speech,” not its own discretion, to make decisions about what to censor.

The nonprofit, known as PragerU, alleges that by limiting access to some of its videos without clear criteria YouTube is infringing on PragerU’s First Amendment rights.

YouTube said it didn’t have immediate comment because it hadn’t yet reviewed the suit. {snip}

The suit heightens a debate over tech companies’ increasing influence on public opinion and how they should police content on their sites. With the internet enabling the spread of misinformation, hate speech and foreign propaganda — especially around the 2016 U.S. election — politicians, academics and the media are increasing scrutiny on the role a handful of tech giants play in modern society.

Since last year, more than three dozen PragerU videos — on subjects including the Korean War and Israel and Palestine — have been restricted by YouTube. As a result, those who use YouTube in “restricted mode,” including students at some universities and children whose parents have put parental control filters in place, are prevented from seeing the videos; all potential ad revenue from the videos is also cut off.

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YouTube has long championed itself as an open platform for ideas and is more often criticized for its reluctance or delay in removing objectionable content. “We believe everyone should have a voice,” YouTube said in a blog post in March. “Since our founding, free expression has been one of our core values.”

PragerU’s suit fits into more recent criticism from YouTube-video creators of the site’s push to remove ads from certain videos — prompted by a backlash from advertisers.

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