(NEW YORK) -- A 50-year-old triple homicide case has finally been closed, after a suspect's son provided clues that led investigators to the so-called Dixie Mafia, authorities said.
On Feb. 3, 1972, a family of three was found murdered in their home in Boone, North Carolina, during a snowstorm. Bryce Durham, 51, his wife, Virginia, 44, and their 18-year-old son, Bobby, had been strangled to death. The couple's son-in-law, Troy Hall, found the family in their bathroom after he and his wife, Ginny, went to check on them.
The Watauga County Sheriff's Office had been unable to solve the brutal murders for decades -- until a break came in 2019. Investigators received a "very important" tip from Georgia authorities, Watauga County Sheriff Len Hagaman said in a statement.
The White County Sheriff's Office in Georgia had inadvertently come across information that potentially tied the murders to four men -- Billy Sunday Birt, Billy Wayne Davis, Bobby Gene Gaddis and Charles David Reed -- who authorities said were part of a Georgia-based network known as the Dixie Mafia. The group was purported to have committed dozens of violent crimes across the Southeast in the 1960s and 1970s.
While participating in research for a book about Georgia crime at the White County Sheriff's Office, one of Billy Sunday Birt's sons, Shane Birt, claimed that during a prison visit his father "admitted to killing three people in the North Carolina Mountains during a heavy snowstorm," the Watauga County Sheriff's Office said in a statement.
Upon hearing that, the White County Sheriff's Office contacted Watauga County authorities, who started investigating the new lead in the cold case. That included three in-person interviews with the only surviving suspect -- Davis -- between September 2019 and August 2021, authorities said.
"It was these interviews that ultimately helped us determine who was responsible through the corroboration of evidence," the Watauga County Sheriff's Office said. "We are confident that we now know who committed these crimes."
Davis, 81, a convicted murderer serving a life sentence at a correctional facility in Augusta, Georgia, allegedly implicated Billy Sunday Birt, Gaddis and Reed in the Durham case, saying they were engaging in a hired "hit."
"Davis claimed to have acted only as their getaway driver, and that it was the other three men that entered the house that night," the Watauga County Sheriff's Office said. "It remains unclear who solicited the crime against the Durham family."
The Durham case was similar to a 1973 crime in Georgia known as the Fleming case that also involved the four suspects, authorities said.
"This is a much-needed turning point for the Durham case," Hagaman said. "We cannot begin to express our thanks to all the professionals and community members who collaborated for so many years to help resolve this case."
Ginny Durham, whose parents and brother were killed, also thanked those who had worked on the case for decades.
"I know that they sacrificed many days and weekends in order to work on solving this case since 1972," she said in a statement. "I would especially like to thank Len Hagaman, sheriff of Watauga County, who has been involved from the beginning and was dedicated to a closure for myself and my family."
One of Billy Sunday Birt's sons recalled his father apparently talking about the Durham case in an interview with WSOC, the ABC affiliate in Charlotte, North Carolina.
"He'd just sort of hint every once in a while, and he'd say something. On this particular occasion, he told my baby brothers about one time he was in North Carolina in a snowstorm" on a hit, Billy Birt told the station. "And that was the clue that connected the dots."
Billy Sunday Birt died in 2017 while serving a life sentence for three murders committed in the 1970s.
"They was a loose group of locals that learnt how to rub two quarters together to make a dollar without working, and got away with it for 15 years and hauled more whiskey than anyone in history in those 15 years," Billy Birt said of the origins of the Dixie Mafia. "And that led to other things: bank robberies ... murder for hire."
Pat Maddux, whose late husband was a North Carolina State Bureau of Investigation agent who spent years following leads in the Durham case, told WSOC-TV that the resolution is a "big relief to all of us here."
"The biggest case, I guess, we have had in Boone," she said. "Something like that has never happened here before."
ABC News' Victoria Arancio contributed to this report.