Whistleblower: Facebook’s artificial intelligence systems only catch ‘very tiny minority’ of offending content

For decades, big tech companies have leaned on a little-known law to avoid being held responsible for some of the most controversial content on their platforms — Section 230 of the Communications Decency Act.

They have invoked it repeatedly in court cases to dismiss potentially costly lawsuits over messages, videos and other content created by users.

What does Section 230 do?

Under the law, tech companies can’t be sued for trying to do the right thing, though the federal government can still sue platforms over criminal content.

The original intent behind Section 230 was to nurture startups and entrepreneurs. One of its key architects, Sen. Ron Wyden, has said that without the law, “all online media would face an onslaught of bad-faith lawsuits and pressure campaigns from the powerful.”

The seemingly simple language of Section 230 belies the sweeping impact it’s had on the tech industry. Under Section 230, “interactive computer services” are considered legally separate from the users who generate their content. They can’t be said to publish or “speak” the words of their users.

How do tech companies use this law?

In practice, courts have repeatedly accepted Section 230 as a defense against claims of defamation, negligence and other allegations. In the past, it’s protected AOL, Craigslist, Google and Yahoo, building up a body of law so broad and influential that Section 230 has come to be described as “the 26 words that created the internet.”

The Internet Association, a major trade group that represents Amazon (AMZN), Facebook and Google, has called Section 230 a “fundamental pillar” of the modern internet, saying it protects not just tech companies but all groups that offer a space for online communications, including schools, libraries, churches, or neighborhood organizations.

But the immense scrutiny facing Big Tech — on everything from election security to privacy — has created a ripe political environment for questioning Silicon Valley’s most important legal shield.