SACRAMENTO, Calif. >> Throughout 1977, the terrified residents of Sacramento County wanted to know when their horror movie of an existence would end. In packed community forums, they expressed their fears about the sadistic predator who was committing sexual assaults in their previously tranquil neighborhoods every few days — someone nicknamed the East Area Rapist.

At one gathering, in a school cafeteria, a Sacramento sheriff’s detective named Carol Daly gave a brief tutorial about defending oneself against the attacker. But before the few hundred audience members dispersed into the California night, a man questioned how anyone could possibly get away with raping a woman in the presence of her husband, who would do everything in his power to prevent an assault.

A few months later, the East Area Rapist targeted that very man and his wife, in one of the more brutal attacks of the dozens he had committed. Daly, now retired, said Friday that she has no doubt:

“The rapist was there at that meeting.”

The horrifying moment reflected how the meticulous criminal — whom investigators strongly suspected had law enforcement connections — taunted his pursuers with catch-me-if-you-can brio. He was flaunting his power, it seemed, as well as his belief that he could elude accountability forever.

He was wrong.

On Tuesday morning, Joseph James DeAngelo, 72, was a retiree and former police officer, known to his neighbors as an occasional crank obsessed with lawn care. By that night, he had been arrested as the suspected East Area Rapist, aka the Original Night Stalker, aka the Diamond Knot Killer — aka the Golden State Killer.

The widely disseminated mug shot of the older, balding DeAngelo, juxtaposed beside a decades-old police sketch of a young suspect with longish hair parted in the middle, twinned the distance of the long-ago with the immediacy of now.

Beyond Sacramento, that year of 1977 unfolded apace: a new president named Jimmy Carter; a hot movie called “Star Wars”; the death of Elvis. But in and around the capital city of California, reports of yet another horrific attack by the East Area Rapist overshadowed everyday life, becoming the obsession of, among others, Daly.

The first occurred in June 1976. Then another in July, in August, in September. After several more in October, law enforcement officials announced that they were looking for one perpetrator tied to attack after attack.

The attacks were devastating to women and their families. But Linda O’Dell, one of the victims, recalled Daly’s deftness, at a time when victims of rape were often re-victimized by the law enforcement procedures that followed. “She was a trailblazer,” O’Dell said of the detective. “She was very comforting to me.”

Investigators soon developed an outline of their suspect: an agile young man, just under 6 feet tall and with a size 9 shoe, whose tactical precision suggested military or law enforcement experience. He was also particularly audacious: After a local newspaper noted that he raped his victims when no man was at home, Daly recalled, he began assaulting women while tying up their husbands.

“He was so in tune with what we were doing and what was in the media,” she said. “And every time we would say, ‘Well, he didn’t do this,’ it was: ‘Ha-ha. I gotcha. I could do it.’”

This calculated audacity fed into the suspicion that, at the very least, the perpetrator had had law enforcement training.

“At the time,” Daly said, “it was a strong enough suspicion that he could have been law enforcement that all of the men in our department who matched his description came forward and got themselves eliminated,” through blood tests matched with a sample of the rapist’s blood.

Monica Miller, the head of the Sacramento FBI field office from 2013 to 2017, agreed that the predator’s patterns suggested that he either knew what the police would look for at a crime scene or had inside information into the investigation.

“He was extremely wily,” Miller said. “Just the way he was able to elude the U.S. He was smarter than the average person when it came to tactics or techniques.”

The rapist flashed his boldness again after that community forum at which the audience member expressed his doubt that a woman could be attacked with a man in the house. And the subsequent assault on his wife, Daly recalled, was especially savage.

“They were all savage,” she said. “But he just seemed to have spent more time in that home, with repeated assaults. I think he was thumbing his nose at everybody.”

At this time, DeAngelo was a police officer in Auburn, a community tucked into the Northern California foothills, not far from where he had attended high school. He wore the light blue uniform, patrolled the quaint streets and responded to routine calls — all while the residents of Auburn were being rattled by reports of the East Area Rapist.

Nicholas Willick, an Auburn police officer who served with DeAngelo and who later became police chief, recalled the tenor of the time, with people installing alarm systems, packing handguns and buying guard dogs.

“We were getting besieged with phone calls wanting an officer to come over to the house to make security checks and make suggestions on how they could make their houses more safe,” Willick recalled. “Because people were afraid.”

In February 1978, a married couple, Brian and Katie Maggiore, were shot to death while walking their dog in the Sacramento County city of Rancho Cordova. This would turn out to be the first murder linked to the East Area Rapist.

The next year, in early July, Willick fired DeAngelo from the police force after he was arrested for trying to steal a hammer and a can of dog repellent from a Pay ‘n Save store by concealing them in his trousers.

Three months later, the serial rapist tied up a couple in the Santa Barbara city of Goleta, nearly 400 miles south of Sacramento. He fled on a bicycle after the woman began screaming.

The next month, in November, DeAngelo took the stand to deny that he was trying to steal the items. Found guilty, he was given a $100 fine and six months’ probation.

The rapes and murders continued for years in California locations far beyond Sacramento County. All the while, Daly retained a large red binder packed with reports and photos and interviews — a resource she often shared with investigators who came after her.

“This is something that, once it’s been with you, it does not leave you,” she said.

In 1986, the predator’s 12-year rampage of break-ins, violence and death stopped — at least, it seems, in California. Twelve dead, at least 50 women raped, and more than 120 homes burglarized.

The reasons remain unclear. Daly surmised that the killer had lost his agility to outrun police officers, or perhaps had come so close to getting caught that he decided to stop. “I felt that something happened that he just wasn’t able to do those crimes anymore,” she said.

Interest in the case waxed and waned over the decades. In 2001, advancements in DNA technology led to the establishment of a link between rapes in Northern California and murders in Southern California. In 2013, the crime writer Michelle McNamara shined a spotlight on the case with an article in Los Angeles magazine. And in 2016, the FBI and the Sacramento County district attorney’s office announced a renewed effort to solve it.

DeAngelo and his wife had three daughters, but at some point the couple separated. He worked for more than a quarter-century at a distribution center for the Save Mart grocery story chain in Roseville, outside Sacramento. He retired in 2017 and was noticed, if at all, for his painstaking lawn care, and for occasional outbursts of obscenity.

Then, on Tuesday, the police came for a fallen member of their fraternity. Daly, long-retired, was among those who got a heads-up call, and 40 years of emotions welled up.

“It’s been borderline tears from the time I got the phone call,” she said.

Late last year, law enforcement officials had uploaded the suspect’s DNA profile, culled from the scene of a 1980 double murder in Ventura County, to a website dedicated to genealogy. That approach was a Hail Mary from Paul Holes, an investigator with the Contra Costa County district attorney’s office who had worked the case for 24 years and was about to retire.

Four months of sleuthing on the genealogy website led to distant relatives of DeAngelo, and from there genealogists helped pinpoint DeAngelo himself — whose DNA, taken from items he discarded outside his home, was a match with the killer’s, according to the police.

On Friday afternoon, DeAngelo was rolled into a Sacramento County courtroom, his wrists shackled to his government-issued wheelchair. He wore an orange jumpsuit with “Sacramento Co Prisoner” stenciled in large letters on the back.

Judge Michael W. Sweet ascertained, after some difficulty, that the defendant’s name was Joseph James DeAngelo. He then recited the charges, including the murder of Katie Maggiore — “a human being” — and of Brian Maggiore — “a human being.”

The former police officer gazed at the judge, blinking slowly and with his mouth partly open, as if there were no words. Then he was wheeled away.

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