A man who murdered his sister and nephew before killing himself last month in La Plata County faced a cascade of troubles: His mother had just died, he was embroiled in an inheritance battle, he was being evicted from his home and he was being investigated for possession of child pornography.
Investigators said they have concluded their investigation into the double murder-suicide, calling it the first such case they can recall in this area.
According to interviews and incident reports, this is what happened:
About 12:30 p.m. June 8, William “Klatt” Decker, 69, left a message with the U.S. Department of Homeland Security, which was investigating him for possession of child pornography.
In the message, Decker said the agency needed to have some “strangers” – he was referring to police officers – come to the ranch where he lived in southwest La Plata County just north of New Mexico on La Plata Highway (Colorado Highway 140).
He didn’t say anything more.
Homeland Security relayed the message to the La Plata County Sheriff’s Office, which sent three law-enforcement officers to investigate.
They arrived about 2:30 p.m. to find Decker hanging from a rope inside a barn with a pistol nearby on the ground. According to investigators, Decker climbed a ladder, tied a nylon rope to a rafter, tied the other end around his neck and shot himself in the head with a .45-caliber pistol.
A handwritten note found nearby mentioned his sister, Billie Decker, 67, and his nephew, Robert “Duke” Decker, 40.
“You’ll find Duke down by the river under the third wire basket,” the letter said, referring to one of three wire baskets used to keep deer away from trees. “You’ll need to go get Billie Decker from her Riverview address. She will be in her upstairs bedroom.”
Investigators walked a short distance to the river where they found a pile of dirt with a boot heel sticking out. Buried in the shallow grave was Duke Decker.
Anthropologists from Fort Lewis College helped excavate the burial site – not because it contained old bones, rather, to avoid disturbing potential evidence.
Investigators said Duke died about 6 p.m. June 7, a day before Klatt Decker shot himself.
They believe Duke, who also lived at the ranch, was arriving home from work and was walking to the house from his truck when he was struck by two bullets, one that pierced his right shoulder and another that landed in his upper back.
Based on evidence at the scene, investigators said he was incapacitated by the gunshots, and Klatt walked up to him and hit him over the head with an 18-inch rusty pipe wrench.
A medical examiner ruled the cause of death to be blunt-force trauma to the head.
Klatt Decker put his nephew’s body onto the bed of a pickup, drove it 50 feet to the river, wrapped it in a tarp and buried it. The pipe wrench was found under Duke’s head in the shallow grave.
The Sheriff’s Office asked the Durango Police Department to check on Billie Decker. Officers went to her house at 242 Riverview Drive where they found her in the upstairs bedroom in a kneeling position on the floor with a rope tied around her neck. The 20-foot rope was strung over her bedroom door and tied off to a door knob across the hall.
Investigators believe Klatt Decker entered her house and killed her without a struggle between 4 and 5 p.m. – two hours before he killed Duke Decker.
Billie Decker had a fatal head wound caused by an 18-inch pipe wrench, investigators said. The medical examiner said she died from hanging and blunt-force trauma to the head.
Klatt Decker had a tough couple of months leading up to the murders, and it appears he blamed his sister and nephew for some of those problems:
On April 4, federal authorities executed a search warrant at his house and seized computers and other items suspected of being used to download or receive child pornography. Even though Klatt is dead, federal officials continue to investigate the origins of the child porn.
Two days later, on April 6, Klatt Decker’s mother, Margaret “Maggie” Decker, died. She left her 750-acre ranch to her grandson, Duke Decker, rather than to her son, Klatt, which set off an inheritance battle.
A week to 10 days before the killings, Duke Decker served his uncle with eviction papers – giving him 10 days to vacate a trailer on the property. Klatt Decker packed all of his belongings, and it appeared as though he had a place to go. But the deal apparently fell through.
Investigators said they are unsure why Klatt Decker took the time to bury his nephew.
It is possible he planned to cover up his tracks. Or the burial was the culmination of his murderous rampage.
The medical examiner noted that Duke Decker had several broken ribs, suggesting Klatt Decker kicked him in the side, said sheriff’s Investigator Ed Phippen.
“It appeared that he was extremely upset and it got directed at the family,” he said.