Senators press TikTok on ‘sinister’ experiment that held back an algorithm safety feature

US Senators Marsha Blackburn and Richard Blumenthal have written to TikTok's top executives demanding answers about an algorithm experiment that reportedly withheld a safety feature from millions of users, including a teenager who later died by suicide. The 2021 feature was designed to stop users being trapped in repetitive "filter bubbles" of harmful content, but TikTok allegedly kept a control group of users without it so it could measure the change's effect on engagement, according to Bloomberg reporting cited in the letter.

Bloomberg reported that US teenager Chase Nasca died by suicide shortly after his account was placed in the control group, with an internal TikTok document reportedly describing how his account was repeatedly served content on suicide, self-harm and depression beforehand. The senators, both prominent backers of the Kids Online Safety Act, have given TikTok until 1 September to explain the experiment and disclose whether it has ever withheld safety features elsewhere over concerns about engagement or ad revenue. They noted the experiment began shortly after a TikTok official was urged at a congressional hearing to do more to protect children, calling the revelations "appalling" and "sinister." TikTok had not responded to a request for comment at the time of publication.