German data protection officials are taking another look at Facebook's use of photo recognition.
The company's Photo Tag Suggest feature involves a database of faces which is used to make photo-tagging suggestions, and works on an opt-out basis.
Data protection authorities in Ireland, Facebook's European headquarters, last year concluded that the feature was legal, but that Facebook needed to do more to keep users informed about how their data was being used.
In the meantime, the feature's been suspended for new European users of the site.
But according to the BBC, German data protection commissioner Johannes Caspar says it's time that Facebook got on with the job of sorting things out.
"It is to be welcomed that Facebook clearly recognises that the process of collecting biometric data is at least not in accordance with data protection law in Europe," he says. "But Facebook can't just stay halfway there."
He's calling on the company to destroy its existing facial database and ask users for specific consent before using the facial recognition.
However, according to the New York Times, Facebook doesn't plan to do this. Because the feature is legal in Ireland, it says, it complies with European law.
"We have met repeatedly with Facebook but have not been able to get their cooperation on this issue, which has grave implications for personal data," Caspar told the paper.
He says he plans to make a formal request to Facebook on the issue by the end of next month.