University of Zurich researchers used AI bots to test persuasion on Reddit without user consent.
AI chatbots secretly manipulated Reddit users, sparking legal and ethical backlash
Photo Credit: Pexels/Brett Jorndan
In a covert experiment now sparking legal threats, researchers from the University of Zurich deployed artificial intelligence (AI) bots to test how effectively they could sway opinions on Reddit — all without user consent. The bots infiltrated the subreddit r/ChangeMyView, which has nearly four million members and exists to facilitate civil debates on controversial topics. Over time, these AI agents posted more than 1,700 comments while posing as real users, ranging from a male rape survivor minimising trauma to a black man criticising Black Lives Matter. None of the subreddit users were told the posts were created by artificial intelligence.
As per a 404 Media report, the study's findings were not announced until after the experiment had concluded; researchers and moderators of the subreddit revealed their activities and linked to a draft of their results. The draft noted that the bots were between three and six times more persuasive than human commenters, gauged through Reddit's award system for changed opinions.
To customise responses, one artificial intelligence looked through user histories, thereby enhancing the effect. Amazingly, none of the Reddit users seemed to believe that artificial intelligence wrote the comments.
The reaction came quickly. Publicly denouncing the experiment, moderators on r/ChangeMyView mentioned it was immoral and unapproved. Also added that they question whether 'it has not been done before' is a justification. Chief legal officer Ben Lee of Reddit also attacked the research, claiming it breached both fundamental human rights standards and user agreements of the site. Under the pseudonym traceroo, Lee indicated Reddit would seek legal action against the University of Zurich.
After noting objections, the university advised 404 Media it will not publish research findings. The ethics committee has updated guidelines to prevent similar errors in future research initiatives. The results raise the question of how artificial intelligence shapes online discussion, particularly in sensitive or political contexts. The case of Reddit bolsters the “dead internet theory”—that AI-written text now dominates the web.
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