Earlier this week, Facebook followed through on its threats to cut a group of New York University researchers off from its platform. The researchers were part of a project called the Ad Observatory, which recruited volunteers to study how Facebook targets political ads on its platform.

In it decision to ban the researchers, Facebook repeatedly referred to its obligations to the FTC saying it was acting against the researchers “in line with our privacy program under the FTC Order” — a reference to the company’s 2019 settlement with the agency over lax privacy practices. But the social network’s actions were roundly criticized by the research community and free speech advocates, who said the company was preventing legitimate research under the guise of “scraping.” As Wired pointed out, the company’s agreement with the FTC doesn’t even prohibit what the researchers were actually doing.

Now, the FTC has weighed in, calling the company’s explanation of its actions was “misleading” and “inaccurate.” In a sharply worded letter addressed to Mark Zuckerberg, Acting Director of the Bureau of Consumer Protection Samuel Levine, said that he was “disappointed by how your company has conducted itself in this matter.”

“The FTC is committed to protecting the privacy of people, and efforts to shield targeted advertising practices from scrutiny run counter to that mission,” Levine wrote. “Had you honored your commitment to contact us in advance, we would have pointed out that the consent decree does not bar Facebook from creating exceptions for good-faith research in the public interest. Indeed, the FTC supports efforts to shed light on opaque business practices, especially around surveillance-based advertising. While it is not our role to resolve individual disputes between Facebook and third parties, we hope that the company is not invoking privacy – much less the FTC consent order – as a pretext to advance other aims.”