Zuckerberg/Dorsey
© Sky NewsFacebook CEO Mark Zuckerberg • Twitter CEO Jack Dorsey
Twitter will ban all political advertisements starting Nov. 22, the company announced on Wednesday — as rival platform Facebook continued to defend its controversial ad policies.

Both candidate and issue-based ads will be prohibited on Twitter globally, with a few exceptions, including for ads in support of voter registration, CEO Jack Dorsey announced.

"We've made the decision to stop all political advertising on Twitter globally," Dorsey tweeted. "We believe political message reach should be earned, not bought."

But Facebook — which has come under fire this month for allowing politicians to lie in ads and refusing to take down misleading missives — doubled down on its decision. CEO Mark Zuckerberg reportedly told investors on a quarterly earnings call:
"Although I've considered whether we should not carry [political] ads in the past, and I'll continue to do so, on balance so far I've thought we should continue."

"Ads can be an important part of voice — especially for candidates and advocacy groups the media might not otherwise cover so they can get their message into debates."
But Dorsey argues online political advertising "brings significant risk to politics, where it can be used to influence votes and to affect the lives of millions." The changes are not about free expression, but about advertisers paying to force their political message on users, Dorsey continued:
"Paying to increase the reach of political speech has significant ramifications that today's democratic infrastructure may not be prepared to handle. It's worth stepping back in order to address."
He noted that online ads have created new issues for "civic discourse" — like "deep fakes," realistic videos that make it look like people have said or done things they did not.
"These challenges will affect ALL internet communication, not just political ads. Best to focus our efforts on the root problems, without the additional burden and complexity taking money brings. Trying to fix both means fixing neither well, and harms our credibility."
While some, including Zuckerberg, have argued banning political ads will be a boon to incumbents, Dorsey said "we have witnessed many social movements reach massive scale without any political advertising." The tech boss called for "more forward-looking as regulation."

"The internet provides entirely new capabilities, and regulators need to think past the present day to ensure a level playing field," he wrote.

Twitter's decision stands in contrast to fellow Silicon Valley giant Facebook, which last month announced a change to its ad policy. It had previously banned ads that contained information which had been debunked by third-party fact-checking services, but will now allow them for the sake of "newsworthiness."

In a speech in Washington this month, Zuckerberg said:
"Even if we wanted to ban political ads, it's not clear where we'd draw the line. There are many more ads about issues than there are directly about elections. Would we ban all ads about healthcare or immigration or women's empowerment?"
Twitter defines issue ads as ads that "advocate for or against legislative issues of national importance." The new policy will be fully unveiled Nov. 15.