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There’s an old, callous journalistic proverb on news judgment: “If it bleeds, it leads.” In the hierarchy of story promotion, in other words, violence takes precedence. Of course, on the Internet, our attention is not beholden to the design of a newspaper’s front page; we can let our attention wander where it will. But it seems it’s still wandering towards murder.

The website Longform recently published its annual roundup of the best stories of 2015, and of the 10 stories on its “Most Clicked” list, seven are about murder. (And more than seven are violent: The top story doesn’t contain any murder, but it’s about a man who committed arson and sexual assault and led police on a six-week-long manhunt.)

And this isn't just a 2015 trend: “Since we started Longform, stories about sex or murder—not to mention stories about sex and murder—have always been the most popular,” Max Linsky, a co-founder of Longform, told me in an email. “Even when it’s longform, it’s still the Internet.”

The Internet certainly offers nonstop access to gory stories, but people have been fascinated by killers far longer than they've had the ability to Google them.

“Killing people has been big entertainment since the losers of gladiatorial battle and adherents to Christianity were eaten by lions in the Colosseum of Ancient Rome in front of audiences of tens of thousands,” Peter Morall writes in his book Murder and Society. “Our lust for gore seems to be unabated. Two thousand years later, murder can still be relished ‘by proxy.’”

What is it that draws people to stare at the darkest extremes of human behavior? There’s a thrill in the frightening, but you can get that from watching a scary movie. A story of real-life murder, in which someone who actually lived is now dead, in which real people experience the loss of a loved one, is an … ickier thing to be entertained by.

Of course there is journalistic value to these stories, in parsing just how something happened, and why. But in reading and loving them, is the Internet just gawking, using tragedy for titillation?

A little bit, yeah. If a murder feels distant enough—it happened long ago, or far away—people are likely to look at it more like a fictional thriller. And, as I wrote in 2014 about the appeal of serial killers, people derive different pleasures from scary stories (fictional or otherwise):

A 1995 study on why adolescents watch horror films found that “gore watchers,” who professed to enjoy the blood and guts, tended to have low levels of empathy and a strong need for adventure-seeking. “Thrill watchers,” who watched the movies to get the adrenaline rush of being scared, had high levels of adventure-seeking, but also high levels of empathy. Gore watchers tended to identify with the killer and not the victim, while thrill watchers tended not to identify with either killers or victims—they were captivated mainly by the excitement and the mystery. “If the real serial killer comes knocking on your door, then it has real implications,” [Scott] Bonn, [author of Why We Love Serial Killers] says. “But until then, it’s just entertainment.”

An unsolved murder adds an element of mystery, especially if there are bizarre unexplained details like the Zodiac killer’s ciphers, or the terrifying elevator video of Elisa Lam, whose murder was documented in one of the most clicked Longform stories: Josh Dean’s “American Horror Story: The Cecil Hotel.”

People may read to find out what happened, or to stew in a sea of questions that can never be answered. But the mystery that likely compels most of the clicks is the psychological one—how could someone do this? What were their motives? Was something fundamentally wrong with with them, something that could have been detected and prevented?

A bare-bones story of what happened would leave people still grasping to understand. While I imagine stories of gore and violence draw eyeballs the Internet over, it doesn’t surprise me that murders dominate on Longform, which curates stories that dive deep into these questions. There’s something fascinating in taking a stick and poking the black sludge at the darkest reaches of humanity, and seeing if something moves within. It’s morbid curiosity, sure, but also a desire to understand the unbelievable, to fit it in a box you can hold safely in your head.

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