Facebook, Twitter and Google executives have been invited to testify in Washington on Wednesday about foreign influence campaigns and disinformation online ahead of the midterm elections in November.

The problem has been far reaching. Over the summer, Facebook announced the discovery of hundreds of fake pages and user accounts on its site. Some pages appeared to specifically target Americans with divisive messages, using the same tactics that Russian operatives did to influence voters during the 2016 presidential campaigns.

The latest influence campaigns also imitated posts by legitimate pages and groups on Facebook that advocate political beliefs, making it difficult to tell what was a genuine post and what was not. Let’s compare some to see if you can tell the difference. Spoiler: It isn’t easy.

One of these posts was from a genuine Facebook page that supports feminism, and the other was part of an influence campaign. Can you guess which post is from a fake page?

“Resisters” was a fake account that Facebook removed in July. “Feminist News” is a real Facebook page, as far as we can tell. (We asked Facebook to confirm the examples of real accounts used here are in fact authentic, and were told there was no apparent reason to suspect otherwise.)

The Resisters page existed for more than a year and described itself as “online and offline feminist activism against fascism,” according to Facebook and researchers at the Atlantic Council’s Digital Forensic Research Lab, which analyzes disinformation online and works with Facebook.

You may have guessed the post was from a fake page if you looked closely at the language: “Girls make rules and you follow them. If you don’t like it you live. End of the story.”

Broken English is not a sure sign that a post is part of an influence operation. But grammatical errors were a common trait among the Russian ads Facebook disclosed in 2017 — particularly the misuse of “a” and “the,” which don’t exist in the Russian language.

Although Facebook has still not tied this page to Russia, the language used in its posts and several other factors suggest a connection. For one, a Russian account that Facebook removed in 2017 had been set as an administrator of the Resisters page, though “for only seven minutes,” Facebook said. Before being shut down, a Russian account had also shared an event created by the Resisters page with its followers.

And on Twitter, an account with the name “ReSisters” and the handle “@resisteszunion” was identified this year as one created by the Kremlin-backed Internet Research Agency.

The page’s most notable activity was an effort to organize a counterprotest to a conservative rally. It created an Aug. 10 event titled “No Unite the Right 2 — DC” to protest a planned white supremacist rally in Washington. The page coordinated with administrators of other Facebook pages, and persuaded five of them to share the event with their followers.

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