Facebook and its opt-out-by-default policies have struck again, this time with automated photo-tagging through facial recognition, which had been in tests but is now being rolled out internationally.

Bloomberg reports that European Union data-protection regulators say they will investigate the photo-tagging feature. The Article 29 Data Protection Working Party, which advises national data protection agencies that could then potentially establish punishments, will evaluate whether the feature breaks privacy rules, according to member Gerard Lommel's comments to Bloomberg.

Facebook, which calls the feature "Tag Suggestions," admitted it messed up at least a little bit, telling various news outlets "we should have been more clear with people during the roll-out process when this became available to them."

Tag Suggestions are "now available in most countries," according to a Facebook blog post yesterday, which said Facebook users tag more than 100 million photos per day.

The company said facial recognition is meant to address user complaints that tagging photos can become a chore, especially in large albums that depict the same people over and over again.

Facial recognition is one of the touchiest subjects in online privacy, with Google Executive Chairman (and former CEO) Eric Schmidt saying publicly, most recently at D9, that mobile facial recognition is something he personally worked to stop at Google, even after it had already been developed. Apple last year boughta facial recognition company called Polar Rose.

Please see the disclosure about Facebook in my ethics statement.

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