Law enforcement agencies, including Singapore's, are finding social media a useful tool in policing activities, but they need to proceed with caution, point out industry observers.
The value of tapping social networking sites lies in the wealth of public or semi-public information available, said Ilias Chantzos, Symantec's director of government relations for Asia-Pacific and Europe, Middle East and Africa, in an e-mail interview.
"It should not be a surprise that law enforcement authorities may want to consider how their investigations could be assisted by using this technology," he said. "In many ways the use of social media either by a legitimate user or a criminal can provide useful information to anyone who wants to profile that individual, especially so because any information that is posted online usually can't be removed completely."
Bob Yap, head of forensic at KPMG in Singapore, told ZDNet Asia in an e-mail that information on social networks "is certainly used to track down criminal suspects" globally. For instance, Italian police in March arrested Pasquale Manfredi, a Mafia member and murder suspect, through his use of Facebook, he said.
Over in Singapore, three youths were arrested by police in February for allegedly posting racist remarks on Facebook, said Yap, adding that the identities of the youths were "apparently deduced from data on Facebook". A police report made by a citizen initiated the chain of events. The youths were subsequently not charged and released.
In a similar incident, a church pastor was summoned for questioning because of a YouTube video containing insensitive remarks toward another religion. Both cases show at the very least that "if citizens report unlawful activities taking place in the online social media, the government might consider taking action", noted Yap.
Other than contact details, useful data that can be mined from social media include indication of travel plans, uploaded photos as well as contacts' activities, all of which can reveal current or future locations or activities.
When contacted, the Singapore Police Force (SPF) did not confirm if it culls information from social media for investigative work. A spokesperson said in an e-mail, however, that SPF created a Facebook fan page in April 2009 as an additional channel to reach out to Singaporeans.
Besides educating and updating the public, SPF also uses the social networking site to seek assistance in identifying suspects by uploading CCTV images onto the page.
"Although to date no suspects have been nabbed via Facebook yet, the responses have been encouraging," she said. "Some of our fans have pledged to keep a lookout for the suspects, while others have shown their support by indicating that the public needs to play a part in helping the police to arrest [these suspects]."
Tapping on social media, however, is not so straightforward, experts cautioned. Issues such as privacy, ethics and legal procedures often come into play.
Symantec's Chantzos noted the need to balance privacy and crime resolution, but admitted that there may be instances where the seriousness of a crime supersedes the privacy rights of individuals.
"As with telephone tapping, monitoring the social networking activity of an individual who is suspected of a serious crime can be a useful tool for law enforcement to observe relations or even particular activities, [and] map social relationships and networks," he explained.
Also, each country has its own set of laws, which may present legal limitations around the use of social media for law enforcement, he said.
KPMG's Yap added that data on social networking sites is typically stored in the site's country of origin, which further complicates the privacy, data protection and data access question.
"Furthermore, in many jurisdictions, evidence obtained unlawfully is subject to being excluded, and in particularly egregious cases, can prejudice an entire trial."
Yap said there are also legal and procedural requirements pertaining to electronic data that may restrict the use of social media data as court evidence. "In our experience, data from social media tends to be used predominantly for intelligence-gathering purposes," he added.
According to Bryan Tan, director of Keystone Law, evidence collected from social media, like any other type of evidence, is admissible unless there are circumstances such as where the data is not deemed to be reliable.
Another issue facing law enforcement agencies is with the use of entrapment in social media. Entrapment, where police use fake identities to lure suspects, "is sometimes permitted" in Singapore, Tan said in an e-mail.
At the end of the day, though, social networking technologies offer "great benefits" and the use of social networking will continue to grow. Symantec's Chantzos noted: "It is...very important to ensure transparency and an open dialog on the appropriate use of social networking sites for law enforcement, as well as appropriate disclosure of policies related to such practices in each country."