CHICAGO (AP) — His task was to solve a cruel mystery decades after a serial killer’s death.

Sgt. Jason Moran’s work began in a graveyard, his first stop in his quest to identify the eight unknown victims of John Wayne Gacy. More than 30 years had passed since Gacy had murdered 33 young men and boys; most of their remains were found in his crawl space.

Investigators now had more sophisticated crime-solving tools, notably DNA, so the Cook County sheriff’s detective was assigned to find out who was buried in eight anonymous graves.

Almost immediately, Moran had a breakthrough: He helped a family confirm what it had long suspected — Gacy killed their brother.

Since then, though, Moran’s search has led him down a totally unexpected path: He’s cleared 11 unrelated cold cases across America. After eliminating these young men as Gacy victims, he’s pored over DNA results, autopsy reports and Social Security records, enlisted anthropologists, lab technicians, and police in Utah, Colorado, New Jersey and other states — and cracked missing person’s cases that had been dormant for decades.

Most recently, he identified a 16-year-old murder victim in San Francisco who’d been buried 36 years ago with his name unknown. Before that, he helped one family learn what happened to their teenage brother last seen at a New Jersey campground in 1972.

He’s brought comfort to some by proving, through science and dogged research, what they already sensed in their hearts — that their missing loved ones were dead.

He’s brought joy to others, tracking down family members who are alive, stunning discoveries that have reunited brothers and sisters, fathers and sons.

Marveling at this remarkable detour from the ghastly Gacy trail, Moran recalls something he recently told his boss:

“Is it possible that an evil serial killer has done some good?”

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THE EIGHT UNKNOWN

Moran’s work began four years ago after his boss, Cook County Sheriff Tom Dart, made a public appeal: He urged anyone who thought a relative was an unidentified Gacy victim to step forward and submit to a DNA test.

A phone number to field calls started ringing. Emails stacked up. Moran built a database, prioritizing about 170 tips that poured in from more than 20 states, representing some 80 missing young men.

This wasn’t new duty for the detective. A seasoned cold case investigator, he’d seen the anguished faces of families living in limbo. “The saddest people you can ever talk to are the parents of a missing child,” he says. “You don’t want to give up and you don’t want to convince yourself they’re dead.”

Moran focused on those the same age, 14 to 24, and with similar backgrounds to Gacy victims: Many had troubled families or substance abuse problems. Some were gay. Others had worked construction for Gacy, a building contractor who sometimes lured victims by hiring them or pretending to be a police officer. He was executed in 1994.

On TV shows, cold case investigations are fast-paced fiction. In reality, they’re slow-motion fact. Records can be misplaced or tossed, evidence deteriorated or destroyed. It can take months, even years to find the crucial piece of a puzzle.

“You’re telling a story and learning someone’s fate,” Moran says. “You’re doing something for a family. You’re giving them a sense of peace.”

Authorities had removed the jaw bones and teeth of the eight unknown victims, hoping for eventual identification. Decades later, they were buried in buckets in a single pauper’s grave. In 2011, they were exhumed. Moran stashed them in a bag and flew to the University of North Texas Center for Human Identification, where lab workers developed solid DNA profiles for four victims.

For the other four, the entire remains had to be exhumed, an “unnerving process” for the detective, who supervised as the caskets were lifted from the soil. “There’s nothing more private,” he says, “than someone’s final resting place.”

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VICTIM 19 GETS A NAME

One of Moran’s first tips was promising. It came from a family that had approached authorities soon after Gacy’s arrest.

William Bundy’s mother suspected he’d killed her son, but back then dental records were the main forensic tool. There was a hitch: Bundy’s dentist had retired and destroyed all his patients’ records.

Three decades later, Bundy’s mother was dead, but his sister and brother were hungry for answers. Moran took DNA from both.

Bundy seemed a probable Gacy target: He’d hung out in a club in an area the killer frequented, and a friend had provided an important tip: Shortly before his death, Bundy was carrying money he’d earned from construction work.

Within weeks, the siblings’ DNA was linked to Victim 19 (police numbered victims as they were removed from Gacy’s house). But it wasn’t enough for a firm identification.

Moran reviewed Victim 19’s dental records, noticing a big gap between his front teeth and empty spaces where his upper canine teeth had been removed.

He asked Bundy’s sister and brother for photos of William, hoping a smiling image would reveal the gaps.

“I don’t always tell people why I’m asking for things,” Moran says. “That raises their suspicions.”

There were no photos, but they had something better. As a teen, Bundy had his top canine teeth removed and saved them because they looked cool. His sister had kept them all these years. When she handed them to Moran, he had proof: Bundy was Victim 19.

Later, he escorted the family to a gravestone marked simply, “We Remembered” — the inscription for each of the unidentified eight.

It turned out Bundy had been buried in a cemetery his family had visited to pay respects to other relatives, not knowing he was there.

So far, Bundy is the only Gacy victim Moran has identified. But there were leads from other families who’d suspected their missing loved ones had died at Gacy’s hands, and Moran’s work was just beginning. Over time, he became a confidant, comforter and friend to many of them.

In every Gacy-related case involving DNA, Moran told families the results would be entered in CODIS, the federal Combined DNA Index System. If a genetic link ever emerged, he promised to call.

And he did — sometimes years later.

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A TATOO AND FIVE FILLINGS

Moran would have bet a week’s salary Andre Drath was a Gacy victim.

He was the right age, a runaway and had lived near the serial killer.

In 2011, Drath’s half-sister, Willa Wertheimer, told Moran about Andy, whom she hadn’t seen since 1978. The two were like Mutt and Jeff, fishing buddies, playmates, forever bonded by tragedy. Their mother died when she was 5 and he was 7. They had different fathers.

The grief-stricken little boy began getting in trouble. His stepfather turned him over to the state. As a ward, he bounced around in foster homes, where he was abused. He regularly visited his sister. Then one day he disappeared.

“I used to fantasize about finding him,” his sister says. “I thought I would try to help him in any way I could. Maybe he was deeply wounded or on drugs. … I just wanted to hold him and tell him I love him and say I’m sorry about everything that had happened.”

When her DNA eliminated any link to Gacy victims, she assumed the case was closed.

Four years later, a Texas lab worker notified Moran that Wertheimer’s DNA had been linked to an unidentified body found in San Francisco in 1979. For various reasons, that DNA hadn’t been submitted to CODIS until late 2014.

Moran ordered the San Francisco medical examiner’s autopsy report and noticed the man was about Drath’s age, almost 17. He’d been murdered, shot multiple times.

Scanning the reports, Moran’s eyes fixed on a revealing detail: The teen’s right shoulder had a one-word tattoo: Andy.

“Oh my goodness,” Moran muttered.

Moran was confident this was Drath, but wanted more evidence. He went record-hunting closer to home, reviewing Drath’s files from the Illinois agency that supervised him as a ward. Dental records were again critical: Drath had five fillings. So did the teenager buried in the sands of Ocean Beach.

He also found a faded letter in the Illinois files from a San Francisco lawyer trying to get Drath’s guardianship transferred from Chicago — proof the teen had moved.

Last fall, Moran delivered the news to Wertheimer. They chatted casually at first, then he adopted a phrase the military uses to inform families of a death: “I regret to inform you …”

“There are no written rules,” Moran explains, “but you’ve just got to come up with a way to notify people that’s professional and sympathetic.”

For Wertheimer, a psychologist, it was bittersweet.

“I was relieved that he wasn’t hurting or suffering,” she says, “but knowing how he died … I wondered. Did he get a chance to think of me? Did he see it coming? I felt awful.”

San Francisco police have reactivated their investigation, and Moran is dealing with the California cemetery, hoping in the coming weeks to have Drath’s remains exhumed from the pauper’s section.

“I brought her to this point,” he says, “now I’d like to help bring him home.”

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DNA AND BONES

Jason Moran cradled a cream-colored urn as he knocked on the door of the North Side home.

It had been 36 years since Edward Beaudion walked out of that house, a 22-year-old new college graduate heading to a wedding. Now the detective was delivering his cremated remains to his sister, Ruth Rodriguez, and elderly father, Louis.

DNA and old-fashioned police work brought this mystery to a frustrating end.

The case had a named suspect: A petty criminal named Jerry Jackson told police in 1978 that he’d fought with Beaudion in downtown Chicago, punched him, dragged his body into a car, then dumped him in a suburban forest preserve, according to Moran.

Jackson was arrested in Caruthersville, Missouri — about 400 miles away — with the Chevy Nova that Beaudion had been driving. It was his sister’s car; she found a bullet inside. Chicago police also found a gun and the same caliber bullets in Jackson’s house, Moran said.

A search of the Chicago-area woods, though, turned up no body. Jackson was convicted only of stealing the car and taking items from it.

Decades later, Moran agreed to investigate, sensing how painful Beaudion’s disappearance remained to his family. “I really felt the sadness and desperation in their voices,” he says. “They needed to find something out.”

Last year, their DNA — newly added to a federal registry — was linked to skeletal remains that had recently arrived at the Texas lab. Some kids had spotted a leg bone jutting from a shoe while hiking through the wooded area where Jackson said he’d dumped Beaudion’s body.

That discovery was in 2008. Unfortunately, the remains sat on the shelf of the Cook County medical examiner’s office for five years before being sent to be tested. Studying the autopsy report, Moran noticed the leg bone contained a surgical screw in one knee. Beaudion had one, too.

That was enough to confirm his identity — yet that five-year delay thwarted Moran’s bigger plans. While preparing to go to Missouri to arrest Jackson in Beaudion’s death, he received disappointing news: Jackson had died months earlier.

Beaudion’s family accepted the news graciously, though his sister lamented her mother had died not learning what happened to her son. Moran, knowing Rodriguez was a devout Roman Catholic, consoled her. “If you’re a believer,” he said, “Edward was waiting for her in heaven. He was already there. So she knows.”

Moran and Dart, the sheriff, accompanied Rodriguez and her father to the spot where Beaudion had been found. His father planted a cross in the soil. Later, the family sprinkled the area with holy water.

Though Moran knew the Beaudions had suffered for decades, he sensed some relief, too.

“His father told me when he dies, he’ll have Edward’s ashes in his casket and said, ‘All of three of us will be together in perpetuity,'” Moran says. “In a way, I’ve almost given him part of his life back.”

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‘EVERYBODY DESERVES A NAME’

Thousands of miles away, a 75-year-old Army vet had his own lingering questions.

Ron Soden contacted Moran about his younger half-brother, Steven, who’d vanished in 1972.

He’d run away while on a camping trip organized by the New Jersey orphanage where he lived with his sister, April. Their mother had placed them there.

Steven’s father lived in Chicago. Could he have traveled there looking for him? Moran thought it possible, and teamed with New Jersey State Police to work the case.

April’s DNA was ultimately linked with skeletal remains found at New Jersey’s Bass River State Forest, about a mile from where Steven was last seen. That discovery was in 2000, but it wasn’t until 2013 — and more DNA tests from another half-brother — that Steven was identified. His cause of death is unknown, though hypothermia is suspected.

“We always held out that hope … then all of sudden you find out and it’s not there anymore,” says Ron Soden, who lives in Tacoma, Washington. “To realize he probably died at 17 … it’s just a shame his life had to be that way through no fault of his own.”

These poignant stories, Moran says, are a powerful motivator.

“You’ve got these young kids who struggle through their short lives,” he says. “Now they’re anonymous. They don’t have a headstone saying they were ever on this earth. I want them to have some dignity and respect so the world knows they once lived.

“I mean, everybody deserves a name.”

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REUNION

There are happy endings in Moran’s work.

Amazingly, he’s located five men who’d vanished in the 1970s. Each time, he’s been incredulous.

“I don’t want to become a family counselor,” Moran says, “but with all these men I’ve found alive, I scold them and say, ‘Why would you do this to a loving family?’ This is almost unforgivable.”

In 2013, Moran reunited Edyth and Robert Hutton — after 41 years apart.

Edyth had made numerous attempts to find her long-lost brother. She mailed about 300 postcards to various Robert, Rob, Bob and Bobby Huttons nationwide. She periodically placed online classifieds in Oregon, Colorado, New Mexico — places she thought he’d be.

She even asked for help from a relative, a private investigator, who thought he’d located Hutton in Colorado. But when Edyth and her father wrote letters to that address, they were returned as undeliverable. “I thought, shoot, he doesn’t want to be found or he’s the wrong person,” she says.

In 2012, in a last-ditch effort she searched NamUs, a website featuring thousands of missing and unidentified people, narrowing her list to seven. She contacted the respective law enforcement agencies. One person replied: Jason Moran.

Hutton had done construction work, and Moran speculated he might have traveled through Chicago.

Using Hutton’s vital statistics, he thought he’d tracked him to Colorado but when local police arrived, the man was gone. He left no forwarding address.

Moran waited several months for updated information to surface in databases. When the sheriff’s analysts checked again, they found a match in Stevensville, Montana. Moran asked sheriff’s deputies there to knock on the door.

They did — and Hutton opened the door. In a phone call with Moran, he confirmed he was Edyth’s brother. Why, the baffled detective asked, had he cut all family ties?

“He said it was basically because he’d gotten caught up in some hippie-trippy lifestyle, and as time went on it was easier to stay away,” he says.

Moran called Edyth Hutton. “Your brother is alive,” he announced. The siblings re-connected the next day.

“I felt like a hole in my heart had been filled,” she says. “I also felt astonished at how huge that hole was.”

Edyth Hutton says neither she nor her father were angry. “People have a lot of reasons why they disappear.”

Her brother, she says, told her he’d gotten involved with drugs, straightened out and returned to the family’s hometown in California but everyone had moved. He declined to be interviewed for this story.

This year, Robert and Edyth Hutton surprised their father for his 89th birthday. It was the first time since the 1960s they’d all been together.

Robert Hutton recently moved to Nevada to live near his sister. “We see each other almost daily,” she says, “and we love it.”

———

Moran has about 40 more leads to pursue.

Might they lead to more Gacy victims? Might they help solve unrelated cases that have languished for decades?

Moran is determined to unlock more secrets. He already has dramatic reminders of his success: On his walls are posters of teenage boys, their faces frozen in time. Across each one in red letters is a stamp: “Cold Case Cleared.”

He looks at them every day.

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EDITOR’S NOTE — Anyone with tips that might identify the seven remaining Gacy victims can call 708-865-6244 or go to www.cookcountysheriff.org .

Sharon Cohen, a Chicago-based national writer, can be reached at scohen@ap.org. Her work can be found at http://bigstory.ap.org/content/sharon-cohen