The idea that a group of people would team up online to use (misuse?) facial recognition technologies in this way, notably outside professional law enforcement channels, seems like a modern take on vigilante style justice, where the torches of the angry villagers have turned into APIs and algorithms. – do we want to crowdsource justice in this way?
http://techcrunch.com/2011/08/09/google-group-members-to-use-facial-recognition-to-identify-london-rioter/