And though the power of social media policing — facial recognition software, for example, and Twitter apps that can clue detectives into broader criminal networks — seems formidable, there's another catch: Casting wide nets across cyberspace could tread on civil liberties and have a chilling effect on free speech.
"Social media creates a web of people involved in criminal activity and who might know those people, and to be able to see those networks is a pretty amazing thing from a policing perspective," says Kristene Unsworth, an information policy expert at Drexel University, in Philadelphia. "But that's also an incredibly wide, wide net to be searching for wrongdoing. That means we have to be really careful that we're vigilant about questioning these [police] activities, to make sure the checks and balances are rigorous enough that they can deal with this kind of technology."
"A lot of police officers are really concerned about using these technologies," Ms. Unsworth adds. "They don't yet know legally where things stand."
Those concerns are also being debated outside the US. Germany, for example, has banned police from using social media-based facial recognition software in fear it will trample on individual privacy rights. And in Vancouver, police attempts to match riot pictures – including of those who were not caught in the act of doing anything illegal – with the state's driver license bureau's database was cancelled after privacy advocates raised concerns.
In the US, where free speech is enshrined in the Constitution, authorities' attempts to curtail mobilization via social media are also making news. The decision by Bay Area Rapid Transit to temporarily shut down four cell phone transponders on Aug. 11 to scuttle a planned protest against BART police drew widespread criticism from free speech advocates.
On Aug. 5, Cleveland Mayor Frank Jackson vetoed a city council ordinance that would have criminalized the use of social media to incite public disturbances. He felt it was too restrictive of rights to assembly and free speech. "Use of this technology in a criminal way and how we react to it – without throwing away the Constitution – is a challenge we all have," Jackson says.
To help combat "flash mobs" and other crime enabled by social media, a conference called "Social Media, the Internet and Law Enforcement" (SMILE) will convene in Dallas in September.
"With the flash mobs, police are struggling with the rapidity — it's just so fast, and it's new territory for them," says Ms. Stevens of ConnectedCOPS. "They'll catch up, though. I have a great deal of confidence that law enforcement is not going to be outdone."