When people fret about artificial intelligence (AI), it’s not just due to what they see in the future but what they remember from the past – notably the toxic effects of social media.

For years, misinformation and hate speech evaded Facebook’s and Twitter’s policing systems and spread around the globe. Now, deepfakes are infiltrating those same platforms, and while Facebook is still responsible for how bad stuff gets distributed, the AI companies making them have a clean-up role too. Unfortunately, just like the social media firms before them, they’re carrying out that work behind closed doors.