Legal experts warn people's online photos are being used without permission to power facial-recognition technology that could eventually be used for surveillance. Legal experts warn people's online photos are being used without permission to power facial-recognition technology that could eventually be used for surveillance. Said New York University School of Law's Jason Schultz, "This is the dirty little secret of [artificial intelligence] training sets. Researchers often just grab whatever images are available in the wild." IBM recently issued a set of nearly 1 million photos culled from the image-hosting site Flickr, and programmed to describe subjects' appearance, allegedly to help reduce bias in facial recognition; although IBM said Flickr users can opt out of the database, deleting photos is almost impossible.