This week, Twitter’s founder and CEO, Jack Dorsey, announced the company’s plan to ban all political ads on the platform. The ban encompasses paid tweets from candidates as well as “political issues” ads. The announcement received widespread applause, in particular from leading Democratic figures, but far less enthusiasm from those who create, run or research political advertising.

Twitter’s ban on political ads is unnecessarily severe and simplistic, disadvantages challengers, and is likely unenforceable – but it was a great PR move for the company, for now.

As others have pointed out, there is lots of room for nuanced digital ad policy between Facebook’s “everything goes” model and Twitter’s blackout. But Twitter’s new policy is simplistic and likely will have unintended effects.

After Dorsey tweeted the new policy, the Trump campaign released a statement decrying the move, pointing to the ban as more “evidence” for supposed anti-conservative bias. But the last person who needs Twitter ads is Trump. My research indicates that upwards of 80% of Trump tweets end up in news stories, earning him massive amounts of media exposure. The move by Twitter all but ensures a repeat of 2016, when Trump’s Twitter tactics helped gain his campaign an estimated $2bn of earned media coverage.

Challenger campaigns use low-cost digital ads to build lists of supporters, solicit donations, and mobilize volunteers

Moving beyond Trump and the US presidential election, Twitter’s ban on political ads disadvantages challengers and political newcomers. Digital ads are much cheaper than television ads, drawing in a wider scope of candidates, especially for down-ballot races. Though much of the public debate about digital ads focuses on hyped-up fears of nefarious persuasion, many more digital ads are used as an organizational tool. Challenger campaigns use low-cost digital ads to build lists of supporters, solicit donations and mobilize volunteers. Digital ads also allow political newcomers to introduce themselves – a tactic that often only breaks through with paid promotion.

As a smaller platform, Twitter brings in far less revenue in political ads than, say, Facebook. According to Twitter’s CFO ,Ned Segal, the company brought in less than $3m from political ads during the 2018 US midterms. But Twitter offers political newcomers the ability to communicate to a crucial population: journalists and political elites. From Twitter, journalists infer what is newsworthy and tweets that get high engagement on the platform can lead to news coverage. Twitter’s ban on political ads will make it harder for challengers and newcomers to break into the news cycle.

A move to ban political ads still puts Twitter in the position of arbitrating political speech, as it must decide what is – and what is not – political. Identifying candidate ads is relatively straightforward, but identifying political issue ads is anything but. Though the full policy won’t be public until 15 November, Twitter’s policy and legal lead, Vijaya Gadde, offered a working definition: “Ads that advocate for or against legislative issues of national importance (such as: climate change, healthcare, immigration, national security, taxes).” These broad categories are open to vast interpretive flexibility. And like Facebook and Google, Twitter has struggled to categorize ads and arbitrate their content at scale.

Perhaps even more important is, from what perspective(s) will “political issues” be defined? Advocating a certain healthcare policy may be political, but what about advertising locations of healthcare centers? What about women’s healthcare centers? What about women’s healthcare centers like Planned Parenthood? Can they advertise about breast exams? Birth control? Abortions? The broad category of “healthcare” gets fuzzy fast. Of course, defining anything as not political tends to come from a privileged point of view.

With the end of political ads, does that mean the end of the Twitter ad archive? The archive had problems, to be sure, but it did provide a measure of transparency. With a ban policy in place, Twitter should continue to embrace transparency and implement some method for showcasing what ads are rejected for being deemed political. Furthermore, Twitter should establish clear and specified mechanisms to contest these decisions. My research, with Daniel Kreiss, suggests that tech firms’ vagaries around political ad guidelines, decisions and processes leave political users frustrated and leaves tech firms open to charges of conservative bias.

From a PR perspective, though, Twitter’s announcement was a slam dunk. The policy announcement via subtweet – itself pre-emptive and without details – took advantage of the negative focus on Facebook’s everything-is-welcome perspective. Twitter backed Facebook into a moral corner, all to applause from the likes of AOC and HRC. But the messy work of defining political issue ads still makes Twitter an arbiter of political speech – a job they’re not likely to perform well.

For those worried about the impact of digital political advertising on the health of democracies, a far better focus than the content of and the presence of the ads is the means by which they are targeted.