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Facewatch ID app lets you shop rioters from your smart phone

Police have called on the public to identify 3,000 suspected rioters with a free smart phone app for BlackBerry, Android and Apple.

Rounding up the usual suspects? There's an app for that. Police have called on the public to help catch nearly 3,000 of last summer's rioters with the help of a smart phone app.

The Metropolitan Police has added 2,880 photographs of suspected rioters to the new Facewatch ID app. Download the free app for BlackBerry, Android or Apple, browse through the faces, and if you spot someone you know you can shop them to the police.

Photos of wrong'uns can be sorted by postcode to aid you with your virtual identity parade. Recognise a rioter -- or one of 2,000 other faces wanted for separate offences -- and you can send a name and address to police via the app. Bobbies say 29 suspects have already been apprehended during trials of the app.

Some 3,000 people have appeared in court on charges relating to the disturbances in London and around the country in August last year. Sentences have been harsh, even for those who never even took to the street: judges have handed down several years in prison just for creating a Facebook page inciting others to cause trouble.

It may not just be the ill-thought out calls to arms posted in public spaces like Facebook that could get your collar felt -- the government is also planning a Communications Data Bill that allows authorities to monitor email and other communication in close to real time.

Crowd-sourcing to find the faces in the crowd is quite a tech-savvy move by the authorities, who usually prefer to blame social media and technology for society's ills. During the riots, social media such as Twitter and particularly BlackBerry Messenger were blamed for inciting disturbances -- prime minister David Cameron even discussed shutting down Twitter, Facebook and BBM in the aftermath of the riots.

Is this a smart use of technology by the long arm of the law, or an extension of the surveillance state? Tell me your thoughts in the comments or on our Facebook page.