Twitter bans all political advertising on its service, diverging from rival Facebook

Twitter is banning all political advertising from its service, saying social media companies give advertisers an unfair advantage in proliferating highly targeted, misleading messages.

"While internet advertising is incredibly powerful and very effective for commercial advertisers, that power brings significant risks to politics, where it can be used to influence votes to affect the lives of millions," Twitter CEO Jack Dorsey said Wednesday in a series of tweets announcing the new policy.

Dorsey said the company is recognizing that advertising on social media offers an unfair level of targeting compared to other mediums. It is not about free expression, he asserted.

Misleading political ads on social media burst into the spotlight during the 2016 presidential election, when Russian agents took out thousands of ads on Facebook in an attempt to sow political division and influence the election.

"This is about paying for reach. And paying to increase the reach of political speech has significant ramifications that today's democratic infrastructure may not be prepared to handle," he tweeted. "It's worth stepping back in order to address."

Facebook has taken fire since it disclosed earlier in October that it will not fact-check ads by politicians or their campaigns, which could allow them to lie freely. Chief executive Mark Zuckerberg told Congress last week that politicians have the right to free speech on Facebook.

During Facebook's earnings conference call Wednesday — which began less than an hour after Dorsey's tweet — Zuckerberg stood by the company's decision. He emphatically stressed what he called Facebook's deep belief "that political speech is important" and denied any financial motive, noting that political ads make up less than half of a per cent of the company's revenue.

"This is complex stuff. Anyone who says the answer is simple hasn't thought about the nuances and downstream challenges," he said. "I don't think anyone can say that we are not doing what we believe or we haven't thought hard about these issues."

Google had no immediate comment on Twitter's policy change.

The issue suddenly arose in September when Twitter, along with Facebook and Google, refused to remove a misleading video ad from U.S. President Donald Trump's campaign that targeted former vice-president Joe Biden, a leading Democratic presidential candidate.

In response, Democratic Senator Elizabeth Warren, another presidential hopeful, ran an ad on Facebook taking aim at Zuckerberg. The ad falsely claimed that Zuckerberg endorsed Trump for re-election, acknowledging the deliberate falsehood as necessary to make a point.

Critics have called on Facebook to ban all political ads. This includes CNN chief Jeff Zucker, who recently called the policy of allowing lies ludicrous and advised the social media giant to sit out the 2020 election until it can figure out something better.

Montana Gov. Steve Bullock, another Democratic 2020 contender, retweeted Dorsey's announcement, adding the comment, "Good. Your turn, Facebook."

Twitter currently only allows certified campaigns and organizations to run political ads for candidates and issues. The latter tend to advocate on broader issues such as climate change, abortion rights and immigration.

The company said it will make some exceptions, such as allowing ads that encourage voter turnout. It will describe those in a detailed policy it plans to release on Nov. 15.

Federal campaigns are expected to spend the majority of advertising dollars on broadcast and cable channels during the 2020 U.S. election, according to advertising research firm Kantar, and about 20 per cent of the total $6 billion US  in spending on digital ads.

Twitter's new policy will take effect on Nov. 22.