Facebook chief Mark Zuckerberg has claimed that only one percent of posts on the free content ad network carry fake news reports.

Critics have said that Facebook influenced the outcome of the US election—in which voters propelled Donald Trump to the White House—by allowing bogus news stories to be shared on the site.

Late on Saturday, Zuckerberg continued his efforts to dampen Facebook's influence on the hugely divisive election campaigns. He said:

After the election, many people are asking whether fake news contributed to the result, and what our responsibility is to prevent fake news from spreading. These are very important questions and I care deeply about getting them right. I want to do my best to explain what we know here. Of all the content on Facebook, more than 99 percent of what people see is authentic. Only a very small amount is fake news and hoaxes. The hoaxes that do exist are not limited to one partisan view, or even to politics. Overall, this makes it extremely unlikely hoaxes changed the outcome of this election in one direction or the other.

Zuckerberg's carefully-worded post, however, fails to address a key reason behind Facebook's hands-off approach: it doesn't want to be seen as a publisher, because doing so opens the company up to a raft of legal headaches, such as libel claims. Which is why it relies so heavily on users to report fake news, or links to videos of beheadings, or indeed misplaced outrage over an iconic photo.

The Facebook chief noted in his post that the 1.79 billion-strong community of users now have the tools to police "hoaxes and fake news" on the service—which to your correspondent sounds like an impossible task.

"Identifying the 'truth' is complicated," Zuckerberg added. "While some hoaxes can be completely debunked, a greater amount of content, including from mainstream sources, often gets the basic idea right but some details wrong or omitted.

"An even greater volume of stories express an opinion that many will disagree with and flag as incorrect even when factual. I am confident we can find ways for our community to tell us what content is most meaningful, but I believe we must be extremely cautious about becoming arbiters of truth ourselves."

It's worth noting, though, that while Zuckerberg stands by his claim that Facebook didn't have undue sway over the outcome of the US election, he is quick to big up its influence over users' lives to advertisers—its real customers.