A memorial cross of stone for Lindsay Cutshall and her fiance, Jason Allen, is bolted to a cliff at Fish Head Beach near Jenner, Calif. The two were found murdered in 2004. ((Kent Porter /Press Democrat/AP)

The young couple were found on a secluded sliver of shoreline north of Jenner, Calif., zipped into sleeping bags that they had rolled out on the gray sand. Each had been killed by a single shot, fired at close range. Their Bible lay close by, just out of reach of the Pacific Ocean’s pounding surf.

The discovery confounded deputies from the Sonoma County Sheriff’s Office, whose helicopter crew had been answering an unrelated call on Aug. 18, 2004, when they spotted the bodies. Lindsay Cutshall, 22, and her fiance, Jason Allen, 26, had no ties to the area, and authorities were hard-pressed to come up with reasons anyone might want to kill them. The couple, who were both from the Midwest, had been spending the summer working as counselors at Rock-N-Water, a Christian summer camp at the foothills of the Sierra Nevada. Planning to return home in a matter of weeks so they could be married, they had set off together on a weekend road trip up the California coast.

Police quickly ruled out the idea that their deaths could have been a murder-suicide, and there was no evidence that either of the pair had been robbed or sexually assaulted. Until Monday, when the couple’s killer, Shaun Michael Gallon, was sentenced to three consecutive life sentences in prison without the possibility of parole, the motive for the double murder remained a mystery.

Though the 40-year-old didn’t speak on his own behalf, attorneys painted a picture of a deeply tormented man wrestling with his inner demons, according to the San Francisco Chronicle. In 2001, Gallon took “too large a dose of LSD and was never the same after that,” his public defender said, adding that mental health issues appeared to have driven him to commit “senseless” murders. As he drove up Highway 1 on that fateful night in 2004, prosecutors said, Gallon was feeling “upset at his own life.” He decided to pull over and climb down the bluffs to the beach.

There, he saw the sleeping strangers, who he thought were homeless people. At that moment, Gallon reportedly told investigators, he “snapped,” and went back to the car for his gun.

“I was gonna kill them out of spite,” he said.

The self-described survivalist had been on the radar of Sonoma County law enforcement for years, racking up convictions for crimes like illegally hunting abalone and shooting a man with a bow and arrow. On Facebook, he posted unintelligible rants about spaceships, rape fantasies and conspiracy theories, showing off a homemade spear and posing with arrows that he crafted by hand. One family friend, unsettled by his enthusiasm for killing animals, voiced suspicions that he might be behind the murders and told authorities that Gallon had cruelly harpooned a seal and shot a calf.

Gallon often blamed his erratic behavior on his bad experience with LSD, telling detectives that he had planned to move to Oregon to start a family until “one day this guy comes up and gives us a bottle of acid and then . . . everything like . . . exploded,” according to records obtained by the Santa Rosa Press Democrat. Multiple psychologists who evaluated him over the years described him as paranoid, and one theorized that he was already beginning to show signs of mental illness before he ever took the drug.

In 2004, his father sought help, fearing that Gallon would hurt his brother, the paper reported. That same year, Cutshall and Allen were found dead on Fish Head Beach.

Police have speculated that the road-tripping couple tried to get a room at a nearby motel on Aug. 14, 2004, only to find that there were no vacancies. Both loved the outdoors and had some camping gear with them, so they opted to spend the night on the beach instead. Before they went to sleep, they jotted down a message in the visitor log, praising God for the incredible sunset they had witnessed and the perfect two days they had spent together.

“As I stir this Mac & Cheese,” Allen wrote, “I think to myself what a wonderful life.”

Family members became concerned when Cutshall didn’t call home on that Sunday, like she usually did, the Zanesville Times Recorder reported. Then, the camp informed them that the couple hadn’t shown up for work. Three days later, the helicopter found their bodies. Both were fully clothed. Their aging red Ford Tempo was parked exactly where they left it, none of their belongings were missing and Cutshall was still wearing all her jewelry.

“It’s just absolutely senseless,” Cutshall’s father told the Chronicle. “They were two innocent people, with no enemies, having an enjoyable weekend together before their marriage.”

Cutshall, a native of Fresno, Ohio, and Allen, who came from Zeeland, Mich., met at a Bible college in West Virginia. Both were deeply devout Christians planning to devote their lives to youth ministry. Their violent deaths shocked the tiny, fogbound village of Jenner, which is located some 77 miles north of San Francisco, and, for some, brought back memories of the Zodiac killer.

“Those questioned include everyone from a local who lives in a van adorned with photos of sunsets, to a 21-year-old drifter from Wisconsin cited for skateboarding in nearby Fort Bragg, to tourists who dine on racklet of elk and creme brulee at the River’s End restaurant,” the Chronicle reported at the time. Police looked for clues everywhere, even analyzing graffiti left on driftwood, and entertained the possibility that the couple had been killed by a hitchhiker or someone angered by their fervent Christianity.

Within days of the killing, Gallon emerged as a suspect after deputies found him wandering another beach in the area, dressed in a camouflage jumpsuit, according to the Press Democrat. The loaded gun he was carrying turned out to be stolen, and police arrested him on weapons charges.

In Gallon’s apartment, police found a five-gallon tub filled with matchsticks, bullets, lead pipes, fuse cords, clumps of hair and blood. Dead animals were stashed throughout the house — a shark had been chopped into pieces and placed in the refrigerator, and a wild turkey was stuffed in a trash can. But they didn’t find the unusual Marlin .45-caliber rifle that had been used in the campers’ murder.

After being booked into jail, Gallon had called his father and asked him to dispose of his guns, according to the records obtained by the Press Democrat. David Gallon would later tell detectives that he had agreed because he feared his son “was not stable.” In 2013, after confronting his son with a flier about the missing murder weapon, the father committed suicide.

Throughout the years, detectives kept returning to Shaun Gallon as a suspect, the paper reported. They found a dead hawk in a box in his freezer and weapons buried in his yard, but nothing that linked him to the murders. Gallon continued to deny that he had anything to do with the couple’s deaths and refused to take a polygraph test.

Meanwhile, authorities came across countless false leads. In 2009, when a “drifter” named Joseph Henry Burgess was killed in a shootout in the Jemez Mountains in New Mexico, police revealed that he had been a top suspect in the camp counselors’ murder, and was also suspected of killing another unmarried couple who were found dead in sleeping bags on the beach in British Columbia in 1972. Though authorities theorized that disapproval of unwed couples who spent the night together had driven him to kill, and his fingerprints were matched to the Canadian murder scene, they weren’t able to link his DNA to evidence recovered from the California beach.

Then, in 2017, Gallon was arrested on a charge of killing his younger brother with an AR-15. In interviews with detectives, he blamed his brother, Shamus, for holding onto a grudge from childhood, according to the Press Democrat. He also decided to get something else off his chest: He was responsible for murdering the young couple who had been found dead on Fish Head Beach nearly 13 years before.

Gallon directed the detectives to a soda can that he had stashed in a blackberry bush on the side of the road, which contained the spent shell casings that he had picked up before leaving the murder scene. During his confession, he appeared to blame the couple for their own deaths, saying there was a sign at the beach that explicitly prohibited camping, the paper reported. His attorney said Monday that he has expressed remorse, saying that the murders made him “feel wretched inside” and “there’s not a day that goes by that I have not thought of what I’ve done.”

Gallon, who also admitted that he had tried to kill an acquaintance with an improvised package bomb that left one woman with serious injuries, pleaded no contest to the three counts of first-degree murder and one count of attempted murder last month, which allowed him to avoid the death penalty for the consolidated charges.

“He doesn’t have to face the wrath of a piddling little father,” Chris Cutshall said, pointing at his daughter’s killer at Monday’s sentencing hearing. “He has to face the wrath of God.”

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