Experts say related tweets aren't showing up in users' timelines, but the company isn't saying anything.
Twitter is limiting certain tweets from appearing on select user accounts, according to activists—including some that mention a blockbuster report from The Intercept that revealed damning information about the US drone campaign in Syria and Yemen.
It's not clear at the moment whether the disappearing tweets are due to a weird bug, or whether the company is actually censoring mentions of an in-depth report on how the US military relies on largely unconfirmable data to justify assassinations, among other revelations. While some activists claim that they are being censored, however, other users report that everything is working fine on their end.
Paul Dietrich, an activist and independent analyst of government leaks, published a post on his personal blog where he described how tweets related to The Intercept's report called "The Drone Papers," no longer appeared on their authors' timelines. The posts were still viewable if linked to directly, and when the timelines in question were viewed from behind a VPN—which allows users to browse with an IP in another country—the tweets were there.
But when using a US IP address the tweets might as well have never existed on the users' timelines in the first place.
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At least one tweet unrelated to the drone papers also appears to be hidden. On the timeline of Jacob Appelbaum, a Tor Project developer who retweeted posts Dietrich made about the drone papers which no longer appear on his timeline, an innocuous tweet about a Chromebook was also hidden when Motherboard editor Matthew Braga checked using a Canadian IP address. The tweet was visible from the UK.
"It seems clear that Twitter is now engaged in censorship," Appelbaum wrote me in an email. "Censorship without transparency is a deceptive practice. Building automated censorship systems is an intentional political decision by Twitter."
It wouldn't be the first time Twitter has raised the ire of anti-censorship activists. Twitter agreed to remove tweets if they break the law in certain countries in 2012.
Dietrich wrote me in an encrypted email that he also believes Twitter is targeting individual users in addition to IP-based geolocating. When he tried to view disappeared tweets with a US IP address that he often uses to tweet from behind a VPN, the tweets were gone, he wrote. When he tried again with a US IP that he'd never used before, they were visible.
The issue wasn't restricted to Dietrich, Appelbaum, or even critics of the US spying or drone programs writ large. Tweets relating to the drone papers disappeared from the timelines of even critics of The Intercept's reporting on the drone papers, such as security blogger Peter Koop.
"Topping the irony list, Peter Koop asked me to check his timeline for similar issues," Dietrich wrote me in an encrypted email message. "I found one. He had also [retweeted] my article. It's not visible in his timeline from the US, but is in Germany."
Dietrich concludes that the tweet removals may be part of the rollout of a feature that lets Twitter identify abusive tweets and "limit their reach." According to a company blog post from April, the feature is currently in testing, and takes "a wide range of signals and context that frequently correlates with abuse" into account when identifying suspected abusive tweets.
Twitter did not respond to Motherboard's repeated requests for comment. We will update this post if we hear back.
UPDATE, Oct. 21: Twitter spokesperson Rachel Millner provided Motherboard with the following statement in response to this article:
"Earlier this week, an issue caused some Tweets to be delivered inconsistently across browsers and geographies. We've since resolved the issue though affected Tweets may take additional time to correct."
Motherboard requested additional clarification on the issue, but Twitter declined.