One night in 2010, Layla Betts was scanning the internet in her Queensland, Australia, home when she came across a ListVerse Top 10 list of unsolved mysteries. One of the entries stuck with her: a car crash victim who hadn’t been identified 15 years later.

A young man had apparently been picked up as a hitchhiker only to die when the car crashed. The body of the driver was identified, but his passenger had no ID. Only a note addressed to “Jason” was found near the body, which was so severely injured that investigators trying to identify him had to work from an artist’s reconstruction of his face. Because the hitchhiker was wearing a Grateful Dead T-shirt and had two Grateful Dead ticket stubs in his pocket, cyber sleuthing communities dubbed him “Grateful Doe.”

“When I read his case, it really resonated with me,” says Betts, now 26. “Music is so important in my life. I saw a lot of myself in the Grateful Doe, but more importantly, I saw a lot of my friends. I couldn’t imagine someone I loved being unidentified for close to 20 years.”

Betts kept tabs on the case but didn’t have time to do much more than read about it, including the occasional media story and online posts about what little progress others in the amateur sleuthing community had made toward solving it. When she finished college in December 2014, she found more time to dedicate to Grateful Doe — and her efforts had almost immediate and sensational success. After Betts uploaded a poster showing artists’ renditions of Grateful Doe’s face and information about the case to various Reddit threads, it went viral, getting half a million views in two days. One of those views was a man who recognized Grateful Doe as his ex-roommate, Jason. He couldn’t remember Jason’s last name, but another friend was able to send a few photos of Jason to Betts. The resemblance to the sketches of Grateful Doe’s face was uncanny.

Then Betts put up a new poster, asking if anyone could identify Jason. This too went viral and was again seen by the right pair of eyes: a man recognized his half-brother, 19-year-old Jason Callahan, who left home to follow his favorite band and hadn’t been heard from since June 1995. Around the same time, Callahan’s mother left a note on a Facebook group about the case. She then filed a missing person report for her son — the family had assumed he had chosen to stay away, so they didn’t file a report when he initially disappeared. DNA tests later confirmed that Grateful Doe was Callahan. In 2016, Grateful Doe was on a new ListVerse list — “10 Unsolved Mysteries That Have Finally Been Cracked” — though Betts’ work was relegated to a generic description, “Grateful Doe’s face has been spread all over the Internet.”

Two years later, the identification of Jason Callahan remains one of the most impressive accomplishments for armchair digital detectives. And it helped Betts launch a community on Reddit dedicated to finding closure for more families whose loved ones are missing and unidentified. At the height of Grateful Doe’s viral fame, the case was being discussed across multiple subreddits, so a Redditor named Pastor_of_Muppets decided to create a dedicated forum to keep track of them all. And r/GratefulDoe was born.

The subreddit amassed about 500 subscribers in its first few days; it now boasts more than 5,000. Betts and Pastor are the moderators. Like Betts, Pastor had been interested in the case for several years, occasionally checking in to see if there had been any new developments.

“It always stuck with me because I am also a Grateful Dead fan,” says Pastor, who prefers to remain anonymous but says he’s a 30-year-old Michigan man in accounting.

“We built a lovely little community and family of people dedicated to the cause of identifying the unidentified,” Betts says.

While Grateful Doe’s identification was an incredible moment for the subreddit — “I find myself still riding that wave sometimes,” Betts says — it was also the end of the mystery the subreddit was founded on. But followers had begun posting about other unidentified body cases. The subreddit quickly evolved from focusing on one case to sharing information about several. About a month after Betts’ first Imgur post about Grateful Doe, she was back with one for “Fulton County John Doe.” (That case remains unsolved.)

The subreddit is far from the only place on the internet devoted to unidentified bodies, but it does things a little differently than the rest. A decade ago, amateur sleuths might identify a body simply by taking the time to look up unidentified bodies and missing persons reports for possible matches, then calling them into investigators. But now there’s a national database called NamUs that does a lot of this work automatically. Between NamUs and years of amateur sleuth work, there aren’t many matches left to make.

But there are unidentified bodies who are not known missing persons — cases like Jason’s where the family either never filed a report, or filed one but police lost it. If a family isn’t actively looking for a missing loved one, having the information come to them through a viral social media post may be the only chance they’ll ever hear about an unidentified body that could be a match. Many unidentified body cases only get media attention from local outlets where the body is found, and may pre-date social media or even the internet. For example, Callahan’s family in South Carolina would not have heard about the unidentified body found in Virginia on their local media. But a viral social media post has the potential to be seen by people all over the world.

“If you go back and look at Doe cases that have been solved, one recurring commonality is that the individual was never reported missing or wasn’t reported missing until years after their disappearance,” Pastor says. “So it is imperative to get as many eyes looking at these cases as possible in the hope that someone from their past recognizes them.”

“Facebook or Instagram are great, because you get shown things that your friends have liked or shared, and so information could, for lack of a better phrase, fall into the lap of the right person while browsing around on a Tuesday night,” says Betts.

To be sure, there are social media pages and profiles dedicated to missing people and unidentified bodies. But Grateful Doe hopes that organizing its efforts with dedicated social media campaigns will bring the cases to more eyes. Certain cases, suggested by followers, are selected to be “featured” by the site, which includes organized case files on Google Docs that are updated with any new developments or information.

“With every unidentified persons case, you have information spread out all over the internet, on websites such as Doe Network, NamUs, WebSleuths, Wikipedia … the list is endless,” Betts says. “Sometimes, the information on these websites is conflicting, and it’s very difficult to keep track of what is right and what is wrong.”

Forums like Websleuths have been around for so long and are so popular that threads dedicated to some cases may contain hundreds of posts, scattering facts (and inaccuracies) across a decade’s worth of comments. Grateful Doe’s case files make it easy for new or less frequent subreddit followers to get caught up and have dedicated tags to help people looking through the subreddit for posts about a featured case.

“Due to the nature of Reddit, posts can kind of drop into obscurity after a few weeks,” Pastor says. “This was a way to make sure all the information was available to anyone just reading about the case for the first time.”

There are currently 18 cases featured on Grateful Doe, two of which have now been identified. The second was Charles Cornell, whose family mistakenly believed that police filed a missing persons report for him when he disappeared nearly 30 years ago. The case was first featured on Grateful Doe in February 2016; Cornell was identified in December 2016. Michigan State Police said they “encouraged his family to file a police report” after learning about his case “earlier this year.” They did not elaborate on what led to hearing about the case in the first place.

Of course, Reddit generally doesn’t have the best track record when it comes to solving mysteries; the most famous example of this being a subreddit dedicated to finding the identity of the Boston Marathon bomber that ended up blaming the wrong person. For every Jason Callahan, there are hundreds of other cases that amateur sleuths haven’t helped solve. Some of them may even make matters worse.

“Sometimes the exposure can take the information to the right person,” Todd Matthews, director of case management and communications at NamUs, says. “So, it’s the communication and outreach that can actually help in some cases.”

But, he adds, “I’ll admit sometimes a crowd sourcing project can make the water a little muddy and distracting. It is important to take the core information that law enforcement have issued for the purpose of circulation and then ‘amplify’ the message.”

Before Matthews worked for NamUs, he was also an amateur sleuth, obsessed with finding the identity of a murdered woman his father-in-law discovered in 1968. His efforts led to her identification in 1998. He went on to help create the Doe Network and then was approached by the Department of Justice to help develop NamUs. Though his efforts were successful and even led to a job, he’s now wary of large cyber sleuth websites with tens of thousands participants — some of whom can be very aggressive when sending “tips” to law enforcement agencies, or who contact families of missing people and send them unidentified bodies that they think are their loved ones.

“Sometimes you can have too many cooks in the kitchen, sometimes you can be too aggressive,” Matthews says. Some investigating agencies, he says, may stop listening to amateur sleuths altogether. Matthews himself says he gets “massive emails on arm chair theories” from amateur sleuths that can be “too numerous to process.”

Betts says she and Pastor “absolutely try to avoid” such situations by strictly moderating the subreddit to ensure that users aren’t starting “witch hunts.” The number one rule of Grateful Doe is not to contact family members.

As for Betts, who estimates that she spends two or three hours every other day on her offbeat hobby, she plans to keep the subreddit going, promoting and investigating more cases. With podcasts (especially those dedicated to crime and mysteries) taking off recently, she says a podcast is the “next step” for Grateful Doe. Her plan is to devote one episode to each case.

“Sometimes, it still keeps me up at night wondering how perfect the timing was for everything to fall into place as well as it did,” Betts says of solving Grateful Doe. “I’ve gotten a lot of really beautiful comments and messages over the past few years; one of my favorites is when somebody says ‘if I was missing/unidentified … I’d want you on my side.'”

The new season of DARK NET — an eight-part docuseries developed and produced by Vocativ — airs Thursdays at 10 p.m. ET/PT on SHOWTIME.

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