Detectives had searched for four decades for the clue that would unlock the identity of the Golden State Killer, the predator who terrorised California top to bottom with a string of horrific rapes and murders in the '70s and '80s.
Criminal DNA databases produced no hits, sweeps of crime scenes no fingerprints and hefty rewards no definitive tips.
But Paul Holes, an investigator and DNA expert, had a hunch he could create a road map to the killer through his genetics.
Holes used DNA recovered from a crime scene to find the killer's great-great-great grandparents, who lived in the early 1800s.
Branch by painstaking branch, he and a team created about 25 family trees containing thousands of relatives down to the present day.
One fork led to a 72-year-old retiree who was quietly living out his golden years in the Sacramento suburb of Citrus Heights.
Holes was intrigued after learning the man was a disgraced cop who had bought guns during two sprees by the killer.
The test of Holes' novel sleuthing would come in mid-April, when officers scooped an item the man discarded containing his DNA and tested it against the killer's. The shot in the dark produced a match - an improbable ending fit for detective fiction.
Joseph James DeAngelo was arrested in Citrus Heights on April 24.
"Everything else up to this time had failed," Holes said. "For 44 years, law enforcement has been trying to solve this case. No other case has had more resources poured into it in the history of California. I was just stunned."
The role of genetics in the case is well known, but this account reveals for the first time the massive scope, intricate science and sheer doggedness of the effort to catch one of the nation's worst serial predators.
Initial DNA work identified distant relatives - not a suspect.
Holes said a team of five investigators spent four months building out family trees, name by name. They pored over census records, newspaper obituaries, gravesite locators and police and commercial databases to find each relative and, ultimately, DeAngelo.
The Golden State Killer was as clever a criminal as he was sadistic, taunting authorities and staying one step ahead as police say he killed at least 12 people, raped more than 50 and committed 100 burglaries between 1974 and 1986, when his crimes appeared to mysteriously end.
His mayhem touched 10 counties, and he was variously called the East Area rapist, Original nightstalker, Diamond Knot killer and Visalia ransacker, before authorities discovered the various crime sprees appeared to be the work of a single man.
He instilled fear like few others.
Sacramento District Attorney Anne Marie Schubert was a child when the suspect carried out dozens of rapes in the Sacramento area in 1976 and '77. Schubert said her mother put a weapon under her pillow.
"It changed this community," Schubert said. "People referred to him as the boogeyman. It wasn't a matter of if he was coming, it was when, because it happened so much and it went on for so long."
The horror began with the flash of a blinding light.
Linda O'Dell, then 22, said she and her husband were woken around 1 or 2am on May 14, 1977, by an intruder shining a flashlight on their bed.
"Don't move," the man barked.
He threw string to O'Dell and ordered her to tie up her husband. Then the intruder tied O'Dell up himself. He piled plates and bowls on her husband's back and stalked around the house yelling and drinking the couple's beer. Finally, he moved O'Dell to the living room, where he raped her.
"He told me he would cut my husband's ear off and bring it to me if there was any noise," she said.
He eventually took O'Dell's wedding ring, possibly as a souvenir, then slipped out into the night.
The three-hour ordeal bore the terrible hallmarks of a predator who came to be dubbed the East Area rapist. The rape of O'Dell was number 21 attributed to the same man in the Sacramento area in 1976 and '77. Thirty more would follow there and in other communities in northern California.
"This was the most heinous rapist I had ever known," said former detective Carol Daly, who was one of the first to investigate the case for the Sacramento County Sheriff's Department. "The attacks were bizarre, cruel and long-lasting."
They were also cunning, said Richard Shelby, another former detective with the department. Shelby said the East Area Rapist planned meticulously. He watched the victims, broke into their homes and even called them to learn their routines before striking. He always seemed to have an escape route via a stream, trail or field.
With each attack, fear ratcheted higher.
Sales of locks, dogs and guns soared - doubling in Sacramento County between '76 and '77, according to the Sacramento Bee. Daly said burglaries nosedived during that era; she surmised it was because of the gun sales and burglars knowing residents were on edge.
But what truly seemed to set the East Area Rapist apart, Daly said, was his apparent delight in stoking this public terror.
At a forum on the rapes in 1977, Daly recalled a man rose and said he doubted a rapist would be able to rape a woman in front of her husband, since the man would retaliate. Several months later, that man's wife was raped while he was at home, Daly said.
"I can't positively say, but I think the rapist was in the meeting that night," she said.
Despite intense searches, Shelby said, the East Side rapist seemed to anticipate police moves and slip away. At the time, DeAngelo was a police officer in the small northern California town of Auburn.
Maybe it’s just my corner of my the internet, but it feels like we didn’t stop to really process the fact that law enforcement found the golden state killer by tracing dna from information a relative had uploaded to a commercial genealogy site.
— Jody Avirgan (@jodyavirgan) April 27, 2018
If DeAngelo is the East Side rapist, Shelby thinks his police training may have given him an edge. His police radio may have allowed him to listen in as police investigated.
The violence grew.
In February 1978, a young couple from Rancho Cordova, Brian and Katie Maggiore, were shot dead when they fled a confrontation on the street while walking their dog. The killings eventually became the first attributed to the East Area rapist.
The year after the killings, DeAngelo was dismissed from the Auburn force for shoplifting a can of dog repellent and a hammer from a drugstore.
The terror soon shifted to southern California, although it's unclear what DeAngelo was doing or where he was living.
Shortly after Christmas in 1979, a surgeon and a psychologist were shot and killed in their Santa Barbara County apartment. In March 1980, a couple was bludgeoned to death with a piece of firewood in their Ventura County home. The woman was raped. Six more murders would follow, all believed to be the work of a killer who was dubbed the Original Nightstalker.
By 1986, that crime spree appeared to abruptly end.
The reason remains unknown, but Daly and Shelby think the killer may have grown too old to continue the physically demanding attacks and flights. In 2001, DNA evidence linked the East Area rapist and Original Nightstalker cases.
“He was extremely wily.”
— The New York Times (@nytimes) April 28, 2018
How a serial rapist and murderer in California flaunted his power as well as his belief that he could elude accountability forever. He was wrong. https://t.co/qL1j1QzHCV
The search for the Golden State Killer helped spur advances in criminal justice. The brother of one victim successfully lobbied to expand the collection of DNA from criminals in California, and the Sacramento Sheriff's Department added a dedicated sex crimes unit.
The final push to find the killer would spawn one more investigative innovation.
Paul Holes had been tracking the Golden State Killer for 24 years, but time was running out. He had nine months before he retired as an investigator for the Contra Costa County district attorney's office, and he desperately wanted to crack his biggest case.
Holes had been obsessed with the Golden State Killer since coming across the case file in the mid-'90s while working as a forensic scientist. Holes had handled serial predator cases, but the Golden State Killer stood out even among these hardened offenders.
"I was struck by the lengths this predator would go to to instill fear in his victims," Holes said. "It was psychological terror."
A detective told Holes about a 2002 case in which a young kidnapping victim was identified using her DNA and a genealogy website. Holes wondered: Could he do the same with the Golden State Killer?
Holes began researching and hit upon a novel tool in GEDmatch, a no-frills website that allows users to upload their genetic information and search a database of roughly a million profiles for possible family connections.
A DNA site helped authorities crack the Golden State Killer case. Here's what you should know about your genetic data privacy https://t.co/fxA0sFGnqf
— TIME (@TIME) April 30, 2018
He prepared to sell the unorthodox idea to officials to get a sample of the killer's DNA.
"We ended up going on a road show," Holes said.
Holes and an FBI lawyer found a partner in Ventura County last summer. A meticulous pathologist had put a duplicate evidence kit from the rape and murder of Charlene and Lyman Smith in a freezer in 1980. Many other DNA samples from the case had been depleted over the years.
A lab converted the sample into a format that could be read by GEDmatch, which analyses hundreds of thousands of DNA datapoints to determine relatedness. Holes waited anxiously as he fed in the killer's profile.
Holes, prepared for another dead end, was heartened when the analysis returned. It wasn't a close match, but the site found 10 to 20 distant relatives of the killer, roughly the equivalent of third cousins.
Holes knew that if he traced back the lineages of distant cousins far enough he could find a common ancestor they shared with the killer. That turned out to be great-great-great grandparents from the early 1800s.
A daunting task lay ahead as Holes and his team began to trace offspring to the present day to find potential suspects. That meant filling in thousands of blanks.
"When you go that far back in time, you have trees that grow huge," Holes said.
The number of people who have had their DNA analyzed has increased dramatically in recent years: the two leading companies alone have reportedly tested 10 million people. https://t.co/KdX6INnKmM
— NPR (@NPR) April 28, 2018
They used census data, old newspaper clippings and a gravesite locator to find the deceased relatives. When they got to the current day, they turned to police databases and websites such as Lexis Nexis.
Holes created his family trees using a tool on ancestry.com. His team stole time on weekends and during meetings to plug the holes one by one. It was tedious work, and it wasn't their full-time focus.
By April, they had pieced together about 25 distinct family trees from the great-great-great grandparents. There were roughly 1000 family members just in the one that included DeAngelo.
The team began scouring the trees for potential suspects, men about the killer's age who had connections to Sacramento and other locations of the crimes.
They found two.
Holes said the other suspect looked promising on paper but was eventually eliminated by a DNA test of a relative. That left DeAngelo.
Golden State Killer suspect on suicide watch. https://t.co/f7E1OFvObT pic.twitter.com/OMWp3JTrcW
— Fox News (@FoxNews) April 28, 2018
Holes had doubts. "How could this guy be a full-time law enforcement officer and be committing all these attacks across northern California?" he said. "I had my reservations that it was him."
Sacramento sheriff's deputies put DeAngelo under surveillance and picked up the discarded item containing his DNA. After the hit, they arrested DeAngelo at his home, not far from where he allegedly carried out many of his crimes. He now faces eight counts of murder.
DeAngelo, whose attorney did not return calls for comment for this report, was pushed into a Sacramento courtroom in a wheelchair to face arraignment. He appeared frail in an orange jumpsuit, answering a judge's questions in a thin, raspy voice.
Holes said he was gratified to finally put a face to the ghost he chased for so many years.
"Thousands of nightmares and thousands of sleepless nights have been put to an end with the capture of this rapist," said Carol Daly.
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