Sonoma County survivalist charged with mysterious killings on Jenner beach

A Sonoma County survivalist who has long been known for strange and violent behavior — and who already stood accused of gunning down his brother — has been charged with murdering a young engaged couple in August 2004 as they lay in sleeping bags on a beach in Jenner.

Shaun Michael Gallon, the lead suspect in the Jenner case for the past year, faces two counts of murder in the rifle killings of Lindsay Cutshall, 22, of Fresno, Ohio, and her 26-year-old fiance, Jason Allen of Zeeland, Mich.

Gallon, 39, is eligible for the death penalty or life in prison without the possibility of parole if convicted, but Sonoma County prosecutors have not said whether they will seek execution.

The Sonoma County public defender’s office, which is representing Gallon, could not immediately be reached for comment Wednesday.

The charges, filed last week, are a major step in a long-running cold case. Sonoma County sheriff’s investigators spent more than a dozen years pursuing the beach gunman, searching for suspects across the country while looking at gun records and eying serial killers.

Gallon was long considered a “person of interest” in the slayings, but the break in the case did not come until March 24, 2017, when Gallon allegedly killed his younger brother in Forestville, shooting him multiple times.

Investigators said Gallon, after being arrested, confessed enough to police to tie him to the killings of Cutshall and Allen. But prosecutors held off on filing charges as detectives continued to dig into the case.

The allegations say Gallon, who was 25 at the time, shot the pair with a .45-caliber Marlin rifle at close range as they slept on secluded Fish Head Beach near the mouth of the Russian River.

The couple had been working that summer at a Christian youth camp along the American River in El Dorado County, and had gone on a three-day sightseeing trip up the coast that would have taken them through Forestville.

Investigators said Cutshall and Allen didn’t know Gallon, though it’s unclear whether they might have had an interaction with him hours before their deaths.

A motive has been elusive in the beach killings, as in the shooting of Gallon’s brother.

On that day, the mother of the two men called for help, saying 36-year-old Shamus Gallon had been shot with a rifle at the home where the family lived on the 9800 block of River Road. The family had moved to the home from Guerneville after the brothers’ father killed himself in 2013.

The mother reported that Shaun Gallon had left the house with the rifle and driven away in his minivan, officials said. He was swiftly apprehended.

It wasn’t Gallon’s first brush with the law. He was convicted of assault with a deadly weapon for shooting an arrow at a man in Guerneville, just west of Forestville, on Jan. 27, 2009.

Gallon, described by investigators in that case as a survivalist, served a three-year sentence — spending some of his time at San Quentin State Prison — after wounding James McNeil of Monte Rio, who was sitting in a parked convertible on Mill Street when an arrow came through the soft top of the car and grazed his head.

Gallon had convictions in his 20s for resisting arrest, weapons possession, theft, drunken driving and hunting abalone without proper paperwork, records show.

Cutshall and Allen were killed sometime after nightfall on Aug. 14, 2004, and before sunrise Aug. 16, officials said. Their bodies were found in their sleeping bags Aug. 18. Both were shot in the head. Cutshall and Allen were killed just weeks before they were to return to the Midwest to get married.

Detectives on the case pursued a number of possible motives in the killings — from sexual assault to murder-suicide, all of which were ruled out.

Megan Cassidy is a San Francisco Chronicle staff writer. Email: Twitter: @meganrcassidy