My friend, Officer Smith

CANADA: Police officers in Canada are spending more and more time chatting on Facebook and sending tweets on Twitter. No, they’re not sitting around the country’s police stations with nothing to do. Using social networks has become a method of fighting crime.

Lauri Stevens, an American social-media consultant, is advising police forces in Ottawa, Toronto and Montreal on how to use social networking sites to prevent criminal activity. “They make friends that way, they make connections that way,” Stevens told CBC News. “And they get inside that world, and they go from there. And in some cases there are some very sophisticated investigations going on in the world of social media.”

"They make friends, and they get inside that world," says Lauri Stevens.

In addition to tracking down criminals, police can — and do — use social networks to contact other groups. Police in Toronto have used Twitter to inform the gay community about their Crime Stoppers programme, which allows people to provide anonymous information to police via telephone, text messaging or online. The Toronto force also used Twitter earlier this year to follow tweets from Tamil protestors who had shut down a busy city highway.

Not everyone agrees that the police should be using social media in this way, however. “There’s a legal and ethical issue here, about the appropriate balance between law enforcement and privacy rights,” says privacy lawyer David Elder. “And I’m not sure exactly where that line is,” Elder adds. “It’s still being set by the courts, and by the privacy commissioner.”