By Nikhila Natarajan New York, Oct 28 : A Congressional grilling of Twitter, Facebook and Google CEOs is quickly evolving into pre-election political circus around the social media content moderation dumpster fire and allegations that Big Tech companies show anti-conservative bias. The US elections are barely a week away and Big Tech's outsize influence is under intense scrutiny. Twitter and Facebook are under fire for their efforts to police misinformation about the elections. Most recently, Twitter and Facebook slapped a misinformation label on content from US President Donald Trump. The Senate Commerce Committee summoned Twitter CEO Jack Dorsey, Facebook's Mark Zuckerberg and Google's Sundar Pichai to testify. The CEOs agreed to appear remotely after being threatened with subpoenas. Section 230, a provision of a 1996 US law that serves as the basis of free speech on the internet, is at the heart of the hearings today. Lawmakers jabbed at the three tech leaders by holding up examples of multiple standards of content moderation - which don't add up. Why are some tweets taken down and others allowed to stay up, multiple Senators asked. Twitter CEO Jack Dorsey explained how Twitter's content moderation policy revolves around tweets that fall into three buckets and not others. Facebook CEO Mark Zuckerberg said that 35,000 people work with Facebook on content moderation and suggested that whatever falls between the cracks is because of the combinatorial formula of algorithmic mediation and human intervention. Senators pushed back against the "idea of unelected San Francisco elites" deciding if content makes the grade or not. In opening statements, Dorsey, Zuckerberg and Pichai spoke to the proposals for changes to Section 230. Zuckerberg said Congress "should update the law to make sure it's working as intended." Google CEO Pichai said that if Google was "acting as a publisher", he would be okay with the company being liable for content published on its platform. Wednesday's hearing comes barely a week after the US Justice Department's landmark antitrust lawsuit against Google, which argues that both advertisers and regular people are harmed by the tech giant's position as "the unchallenged gateway to the internet for billions of users worldwide". /IANS