A new study from researchers at University of Southern California finds that bots are influencing discussions around the U.S.  elections on Twitter. Looking at more than 240 million election-related tweets, the coauthors identified thousands of automated accounts that had posted tweets about President Donald Trump, his Democratic opponent former Vice President Joe Biden, and both of their campaigns. Most of the bots were promoting right-leaning political conspiracies like QAnon and politically biased narratives about the origins of and treatments for the novel coronavirus. And even though the bots are believed to have been responsible for a few million of the tweets, they potentially reached hundreds of thousands of users on Twitter, according to the researchers.

The findings would appear to confirm the fears of some social media experts, who have expressed concern bots will evade even sophisticated filters to amplify misleading information, disrupt get-out-the-vote efforts, and sow confusion in the election’s aftermath. The role bots play in disseminating false and misleading information is well-established. Research by Indiana University scientists found that over a 10-month period between 2016 and 2017, bots targeted influential users through replies and mentions in order to surface untrue stories before they went viral. During the 2017 Catalan referendum for independence in Spain, bots generated and promoted violent content aimed at users calling for independence.

The University of Southern California study, which was published Wednesday by the online peer-reviewed journal First Monday, focused on election-related tweets from June 20 to September 9, 2020 and other data from Twitter during that period. Throughout their analysis, the coauthors identified significant differences among bots and humans and the type of election content they tweet and retweet on the platform. In addition, they examined the political leanings of real human users, common hashtags, and any tweets containing stories or other content from partisan and traditional news media.

Bots almost exclusively retweeted original posts by human users on Twitter, the coauthors of the report concluded. In turn, many humans retweeted bots’ messages that aligned with their political leanings. Right-leaning accounts significantly outnumbered their left-leaning counterparts by 4 to 1 among bots and by 2 to 1 among humans. Meanwhile, users who shared or retweeted news from right-leaning media platforms were almost 12 times more likely to amplify conspiracies than users who promoted left-leaning content (25% versus 2%). Just 4% of the bots retweeted news from left-leaning and centrist media outlets such as The Washington Post, The New York Times, Los Angeles Times, ABC News, BBC, CNN, and others, while about 20% of users that shared content from right-leaning media like Breitbart, OANN, and Infowars were likely bots.

The conspiracy theories that the researchers traced in tweets included “pizzagate,” a debunked claim linking Democratic Party officials and U.S. restaurants with child sex trafficking. About 13% of all users sharing conspiracy narratives were suspected bots, including several from Ghana and Nigeria, which launched information campaigns to target left-leaning users about the Black Lives Matter movement. Saudi Arabia and Turkey also had high engagement with right-leaning users, while Russia and China mostly targeted left-leaning fringe groups and conservative groups.

Twitter has previously disputed the notion that third-party services without access to its internal datasets can accurately detect bot activity. But Ferrara and colleagues’ findings are in line with other investigations of bot activity on the platform conducted to date. A team at Carnegie Mellon found that bots may account for up to 60% of accounts discussing COVID-19 on Twitter and tend to advocate false medical advice, conspiracy theories about the virus, and a push to end lockdowns. And Bot Sentinel, which tracks bot activity on social networks, in early July observed new accounts promoting Black Lives Matter disinformation campaigns, including false assertions that billionaire George Soros is funding the protests and that the killing of George Floyd was a hoax.