For nearly three decades, he was known only as Sand Canyon Joe Doe, the apparent victim of a homicide found in northern Nevada’s high desert.
Now, because of clues developed with DNA technology, genetic genealogy tracing and old-fashioned detective work, the native Californian who also lived in western Nevada has a real name, and state and county investigators are trying to jump-start their search for his killer.
Born in Sacramento, Vincent Marion Trapp served in the U.S. Army in the late 1960s and was 43 years old when investigators believe he was killed in the spring or summer of 1991.
His skeletal remains were discovered in March 1992 after an anonymous tip led sheriff’s deputies to Sand Canyon, roughly 100 miles (161 kilometers) southeast of Reno and 40 miles (64 km) south of Yerington.
Lyon County’s sheriff publicized his photograph this week and issued a new plea for tips.
“We have reached the point we need some more help,” said Lt. Jerry Pattison, who works in the agency’s major crimes division.
Pattison said in an interview Wednesday he was listening to a crime podcast about advances in technology combining DNA science with genealogy data a couple of years ago, and decided it was worth pursuing approval to contract with a lab that specializes in the work.
Last year, detectives began working with Parabon NanoLabs Snapshot of Virginia to narrow the list of potential family members of the victim using genetic matches from a database called GEDmatch.
It’s the same database the Washoe County sheriff’s office used two years ago to finally identify a woman whose body was found in 1982 on a trail at Lake Tahoe, and eventually the man they believe killed her.
They closed that cold case, determining Mary Silvani was killed by James Richard Curry. He served prison time for robbery in California before he confessed to a 1982 murder in Santa Clara and two killings in the San Jose area in 1983. Curry killed himself in jail before he went to trial.
Lyon County detectives said Wednesday the new information in the Trapp case prompted them to travel to two states to interview “persons of interest.” They were able to establish a rudimentary timeline of Trapp’s general whereabouts leading up to his death.
Pattison noted he couldn’t disclose any names or locations, but said they started talking to relatives and collected DNA from a brother.
“That’s how we were able to confirm he was the victim,” he said. “It’s really fascinating.”
Detectives in 2015 did isotope testing of the victim’s hair, which can indicate where someone lived based on the minerals found in a particular region, Pattison said. But in this case, the long list of possibilities ranged from California to the Pacific Northwest, the western Dakotas, Colorado, Wyoming, Utah and Nevada.
“It was like everywhere west of the Mississippi. So, the isotopes didn’t really help us,” Pattison said.
Detectives still don’t know the exact date Trapp moved to Nevada. But they did establish he lived at Topaz Ranch Estates in Douglas County from late 1989 through fall 1990, and in Yerington in spring 1991, Pattison said.
Other clues disclosed previously included a dog photographed during the suspected time window of the killing in the area where Trapp’s body was found. A broken dog collar was found nearby.
“We are hoping someone will call with some new information,” he said.
Pattison said to call him (775-577-5206), Nevada Division of Investigation agent Matthew Wehn (775-684-7412) or Secret Witness (775-322-4900).
Photo: Vincent Marion Trapp. Credit: Lyon County Sheriff's Office
By SCOTT SONNER