The Current

This journalist crowdsources tips to help solve murders in his spare time

Billy Jensen, a true crime writer who helped write a famous book about the Golden State Killer, uses social media crowd sourcing to help solve murder cases in his spare time. Here's how he does it.

True crime writer Billy Jensen was also involved in investigating the Golden State Killer

Billy Jensen is the author of Chase Darkness With Me: How One True-Crime Writer Started Solving Murders. (Robyn Von Swank)

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By day, Billy Jensen is a consultant for digital media companies. But in his spare time, he helps crack unsolved murder cases — with the help of social media and the public.

Jensen uses whatever video and photo might exist of the suspect or the crime scene, and creates ads on Facebook and Twitter that target people in a small geographic area, asking for any clues they may have. He'll often get a flood of potential leads.

No one hires Jensen to do this work. He often has to beg police to follow up on his leads, and he says he has gone into debt to finance the social media ad campaigns.

But Jensen says he has now helped solve 10 murder cases — which makes it all worthwhile.

"It's felt right because it worked," Jensen told The Current's interim host Laura Lynch. "And how could you not?"

Jensen has recently released a book, Chase Darkness with Me: How One True Crime Writer Started Solving Murders.

In it he chronicles how he learned to use social media to help solve murders, how police and citizen detectives can use his methods, and how he helped write the book that elevated the case of the Golden State Killer

From cold cases to solving crimes

Jensen was a crime reporter and investigative journalist for decades, and he was always interested in writing about the unsolved cases. 

"I used to say, 'I hate the guy that got away with it,'" he said. "That's the reason why I do this."

It was that interest that led him to befriend writer Michelle McNamara. She was working on a book about a series of unsolved murders and rapes in California in the 1970s and 80s, coining the name "Golden State Killer" for the then-unknown culprit during her investigation.

Joseph James DeAngelo, known as the Golden State Killer. (Sacramento County Sheriff's Department via Getty Images)

When McNamara died halfway through writing the book, Jensen decided to finish writing it for her.

The killer was eventually found in 2018, not long after the book, I'll Be Gone In The Dark, was published.

Helping write that book lit a fire in Jensen. He was tired of writing about unsolved cases, fed up with seeing families with no closure, and investigators and citizen detectives come up against dead ends.

"And there's this guy [the murderer] selfishly sitting in a corner knowing the answer," he said.

He needed to find a new method to solve the crimes himself.

Sheriff's crime scene tape surrounds the house belonging to Joseph James Deangelo, who was arrested for the East Area Rapist/Original Night Stalker/Golden State Killer case in Citrus Heights, California, U.S., April 25, 2018. REUTERS/Fred Greaves - RC1DEAAD51A0 (Fred Greaves/Reuters)

Using social media to solve murders

Shortly after McNamara's death, Jensen came up with a technique that allowed him to do just that.

In early 2016, a Chicago man named Marcus Gaines died after he was hit by a taxi. Gaines, who was earlier attacked by an unknown assailant, was lying unconscious on the road before he was hit.

Suveillance video of the attack was shot from above, making it difficult to identify the assailant.

Michelle McNamara, right, pictured here with her husband, comedian Patton Oswalt, made it her mission to find the person responsible for at least 12 murders and 50 rapes throughout California in the 1970s and 80s. She died in April 2016. On April 25, 2018, authorities said a DNA match led them to arrest Joseph James DeAngelo, a 72-year-old former police officer, as a suspect. (Matt Sayles/Associated Press)

Jensen created a Facebook page dedicated to the case, and posted ads on Twitter that targeted people in the immediate area. Eventually, someone sent him a photo and video that showed the attack from the front, so that the assailant's face could clearly be identified.

"I couldn't believe it," said Jensen.

He took the information to Chicago police — but, he said, they did nothing. "They just said thank you. That's it," he said.

So Jensen kept on the case.

He identified a suspect named Marcus Moore, and began following him on social media.

Jensen eventually discovered that Moore was staying with his brother, who lived in Minneapolis, and was in a relationship with a woman from Minnesota. Everything was lining up.

"I'm begging with the police: 'He's in Minnesota. He's at his brother's house,'" Jensen said.

It took five months, but eventually U.S. marshals arrested Moore in Minnesota, just as Jensen had predicted. 

Finding a fugitive

Jensen realized he had a formula that he could replicate. So he began looking for other cases.

"As soon as it's solved, it's always, 'Let's go to the next one," he said. "There's 220,000 unsolved murders in America since 1980. There's always going to be a next one."

Some cases, he said, are like "finding a needle in a haystack."

Once, for example, a San Jose police officer asked for Jensen's help finding a fugitive who had committed a murder. 

All police knew about the man's whereabouts was that he was in Mexico — far too large a place to effectively geo-target with ads.

Sunil Tripathi, 22, who had been missing since mid-March, was misidentified by online sleuths as one of the Boston bombers. (Brown University/Associated Press, File)

But then the officer showed him a photo of the man. He was very pale, had red hair, and didn't speak English. 

"This guy is gonna stick out like a sore thumb," Jensen recalled.

So he placed Spanish-language ads on social media asking for information about the man. He honed in on two beach towns, focusing on areas near American bars like Hooters. 

Within hours, messages started pouring in from people who told him they had seen the suspect. Those ads helped police to track the man, Jensen said, and, six months later, they finally caught him.

Ethical questions about crowdsourcing for murders

Crowdsourcing to solve crimes, particularly using digital imagery, present some very serious ethical questions. 

People have been misidentified through images as perpetrators of crimes they did not commit, such as in the high-profile case of Sunil Tripathi, a university student misidentified by amateur online sleuths as one of the 2013 Boston Marathon bombers. Tripathi had gone missing one month before the bombing. 

Jensen said anyone attempting the kind of citizen detective work he advocates must follow a simple rule: "You don't name names in public," he said.

"If you find something, you go to the authorities."

Jensen said many amateur sleuths want to publicly name people they think are suspects because "they want to look smart, or they want to get credit."

Instead, he said, "they're ruining people's lives."

"If you can stay away from that, you can stay away from those miscarriages of justice."

Written by Allie Jaynes. Segment produced by Howard Goldenthal.