Twitter has announced a ban on political advertising ahead of crucial elections in the UK and US over the coming year, turning up the heat on Facebook to tackle micro-targeting campaigns on social media.

At Infosecurity Europe earlier this year, author Jamie Bartlett warned that elections will increasingly be fought online, with small groups of swing voters micro-targeted by personalized ads. This strategy threatens to undermine the legitimacy of results, he argued, and could be further tainted by dubious use of private data, as per the Cambridge Analytica scandal.

Across several posts on the social platform he co-founded, CEO Jack Dorsey, explained that the firm’s final policy would be published on November 15 and enforced a week later.

“We’ve made the decision to stop all political advertising on Twitter globally. We believe political message reach should be earned, not bought. A political message earns reach when people decide to follow an account or retweet. Paying for reach removes that decision, forcing highly optimized and targeted political messages on people. We believe this decision should not be compromised by money,” he said.

“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.”

Although tacitly admitting that the decision would probably have a minimal impact on the firm, given its relatively minor role in a much larger political advertising ecosystem, Dorsey couldn’t resist piling the pressure on Facebook.

“For instance, it‘s not credible for us to say: ‘We’re working hard to stop people from gaming our systems to spread misleading info, buuut if someone pays us to target and force people to see their political ad…well…they can say whatever they want!’,” he argued.

Dorsey also called for “more forward-looking” political advertising regulation, although admitting this would be difficult to craft.

The news was welcomed by non-profit the Open Knowledge Foundation, which called on Facebook to follow suit.

“It will go a considerable way to preventing the spread of disinformation and fake news, and help to resuscitate the three foundations of tolerance, facts and ideas,” argued CEO, Catherine Stihler.

“It is imperative that we do not allow disinformation to blight this year’s UK General Election, forthcoming elections across Europe, and next year’s US Presidential election. Facebook must act on the growing demands for greater transparency.”

Socialbakers CEO Yuval Ben-Itzhak also praised the move as part of Twitter’s efforts to clean up its platform.

“By banning political advertising on the platform, Twitter’s leadership is taking an important stance,” he added. 

“Validating each ad at scale is technically challenging to say the least, so by banning politically-motivated ads the platform stands a better chance of remaining digital pollution-free for its advertisers and users.”

However, Tom Gaffney, security consultant at F-Secure, argued that the real problem for Twitter is fake accounts which are used to amplify often extreme views and misinformation, and trolling, which can also be used to spread rumors.

“Since many fake and troll accounts are controlled at least partially by real people, it is very difficult to create algorithmic methods to detect them” he concluded.

“Despite Twitter’s own efforts, it is clear that the platform is still burdened by the presence of fake accounts and that many manipulation tactics are still very viable. In order to build better detection methods, more research is needed to understand how the people behind these accounts operate.”