I watched in disbelief, horror, and dismay as news broke of Londoners laying waste to their—and my—city. My part of South London, Tulse Hill, escaped the riots, probably for want of anything to steal, but businesses were attacked a mile away in Streatham, and widespread looting hit nearby Brixton. For the past four nights, the wail of police and fire sirens has been a continuous feature of the city's soundtrack.

These events are a godsend for 24-hour rolling news, but they also show its limitations. Like many others, I watched both BBC News and Sky News to find out what was going on. And like many others, I found the TV news incapable of keeping up with the changing situation.

Live text coverage from the BBC, the Guardian, and Sky News fared much better, but it was Twitter—of course—that was the most responsive, most timely source of information about the rioting and looting up and down the country. Raw, uncensored, and unverified though it may be, it was also the best way to learn what was actually going on.

But it didn't take long for Twitter, and its social networking cousins, to come under attack from authorities.

Twitter, tool of collective action



That's because social networking sites have become standard tools in the arsenal of those organizing all kinds of mass action. They offer instant communications and easy ways for groups of like-minded individuals to come together. Systems such as Twitter's hashtags make it easy for ad hoc networks to form around a common interest, act together, and then disband.

In London, police officers were quick to blame Twitter and social networking sites for the organized criminality that has struck across the capital. The move was almost reflexive; Twitter's role in such events is now well-known and expected. Twitter was certainly heavily used during the riots, with Monday setting a record for UK visits to the site.

Perhaps the first widespread use of Twitter to organize a protest was in the aftermath of Moldova's April 2009 election. With the victorious Party of Communists of the Republic of Moldova accused of fraud and rigging the outcome, protest marches were organized. These demonstrations descended into chaos and became a riot, with buildings set ablaze, government offices ransacked, and shops looted.

David Lammy, MP for Tottenham, called for BlackBerry Messenger service to be temporarily suspended.

The original organizers of the protests used Twitter to publicize and promote their action, with their messages soon spreading by blogs, e-mail, and Facebook. Tweets about the protests used the hashtag #pman, short for Piata Marii Adunari Nationale, the name of the largest square in Chisinau, Moldova's capital city. With these networks instrumental in its organization, the movement became widely known as the "Twitter Revolution."

The Iranian election protests of 2009-2010, Tunisian protests of 2010-2011, and Egyptian protests of 2011 all saw Twitter and other social networks used in similar ways: a means for getting messages out and for rallying supporters.

However, although rioters did tweet, and continue to tweet, about their acts of theft and vandalism, the blame has now shifted from Twitter to BlackBerry Messenger (BBM). Rioters appear to have been setting their BBM statuses to tell their friends that they were out looting, and messaging each other to decide the best places to attack.

From the boardroom to the street



BBM might at first seem a strange choice; RIM's core audience for the BlackBerry is enterprise users, and the rioters are primarily (though not exclusively) disaffected teenagers and young adults. But BlackBerry Messenger has a very compelling feature: it's cheap. Though RIM would insist that its BlackBerrys are smartphones, many of them sell at feature phone prices, putting them within reach of many people who can't afford "proper" smartphones. BlackBerrys are also readily available on pay-as-you-go plans, further broadening their availability. BBM can also be cheap to use, with unlimited BlackBerry mail and Messenger typically costing about £5 (around $8) a month—less than most data plans or unlimited text packages.

BlackBerry Messenger has another desirable feature: it's a closed system. Unlike Twitter, where tweets are public broadcasts, or Facebook, where most messages are shared fairly indiscriminately, BBM is private. Most BBM messages are point-to-point, seen only by the sender and the receiver. Group messages are also possible; these too are only visible to those sending or receiving them. The entire system is also encrypted, offering less scope for surveillance by the police.

Unlike protestors campaigning for freedom and openness, for whom public visibility was important, privacy is a desirable characteristic for those engaged in criminality.

The use of BlackBerry Messenger in this way led to David Lammy, MP for Tottenham where the trouble first began, to call (on Twitter) for the service to be temporarily suspended.

For its part, RIM says that in all markets in which its products are available it will "cooperate with local telecommunications operators, law enforcement, and regulatory officials," and that it will assist the authorities "in any way [it] can". Under the Regulation of Investigatory Powers Act (RIPA), the UK police can demand the phone records, location data, and Internet records about specific individuals. This doesn't allow the police to make blanket requests—such as information about everyone in a particular area at a particular time, or everyone messaging the word "riot"—but it does mean that such evidence can be acquired about individuals identified in other ways (CCTV, for example).

RIM insists that it has no way of monitoring or intercepting e-mails sent through its enterprise mail system, but it has provided governments in some countries the ability to eavesdrop on the more consumer-focused BBM. The governments of Saudi Arabia, the UAE, and India have all been given surveillance access to BBM.

RIM's statement that it will comply with local law was not warmly received by hacking group TeaMp0isoN_. TeaMp0isoN_, which a couple of months ago raised its profile by attempting to dox (identify) LulzSec members, hacked into the official BlackBerry blog and posted a message warning RIM against aiding law enforcement. Claiming that any assistance will mean that "innocent members of the public" will "get charged for no reason at all," the post threatened that TeaMp0isoN_ "has access to your database which includes your employees information; e.g - Addresses, Names, Phone Numbers etc.," and that this information will be given to the rioters if RIM provides information to the police.

Though Facebook didn't see the same UK traffic surge that Twitter experienced, it too had a small role to play in the drama. The BBC is reporting that a 17 year-old from Clacton, Essex has been arrested after allegedly using Facebook to incite others to meet up and riot.

Social networks are just a tool. Like any tool, some will use them for ill ends, but many others will put them to positive uses.