LOS ANGELES — Over the last few days, thousands of people have taken to the Internet to play Sherlock Holmes.
Armed with little more than grainy surveillance camera videos, cellphone photos and live tweets from police scanners, they have flooded the Web with clues, tips and speculation about what happened in Boston and who might have been behind it.
Monday’s bombings, the first major terrorist attack on American soil in the age of smartphones, Twitter and Facebook, provided an opportunity for everyone to get involved. Within seconds of the first explosion, the Internet was alive with the collective ideas and reactions of the masses.
But this watershed moment for social media quickly spiraled out of control. Legions of Web sleuths cast suspicion on at least four innocent people, spread innumerable bad tips and heightened the sense of panic and paranoia.
“This is one of the most alarming social media events of our time,” said Siva Vaidhyanathan, a media studies professor at the University of Virginia. “We’re really good at uploading images and unleashing amateurs, but we’re not good with the social norms that would protect the innocent.”
Even as first responders were struggling to tend to the needs of the three killed and more than 170 injured in the Boston Marathon blasts, Web forums were cranking out rumors that there had been four bombs instead of two, that an area library had been targeted and that the death count was well over a dozen.
In short order, forums like Reddit and 4chan were alive with speculation — based on little or no evidence — that the culprits were Muslim fundamentalists or perhaps right-wing extremists.
In a mad rush to be the first to identify the perpetrators, anonymous posters online began openly naming people they believed had planted the bombs. Caught up in the mania, some traditional media ran with that information. Thursday’s New York Post cover showed a photo of two men at the marathon under the headline “Bag Men” and implied the two were prime suspects. In fact, neither was a suspect.
Once the FBI released images of the actual suspects, things really got out of hand. Online gumshoes scoured the Web for faces that might match and illustrated their work with drawings, circles and other home-brewed CSI techniques.
So as the Boston Police Department engaged in a gunfight with the two brothers in Watertown, Mass., early Friday, tens of thousands of Web denizens tuned in to live streams of police scanners, furiously tapping notes and ideas into Reddit and Twitter.
“I feel like we’ve reached a certain threshold here — the Internet is finally outstripping cable news completely,” a poster using the handle PantsGrenades wrote on Reddit. “In fact, I wonder if we’re inadvertently doing their work for them.”
According to Murray Jennex, a crisis management expert at San Diego State University, the huge influx of online voices enabled by social media can be extremely helpful because eyewitnesses are holding cameras in almost every location.
But beyond the photos they upload, their speculation and theorizing don’t necessarily lead to a more efficient resolution.
“There is just a lot of meaningless noise out there,” he said, noting law enforcement and disaster management institutions can be overwhelmed by useless tips in a crisis. “People see trends and patterns that aren’t really trends and patterns.”