Montana Girl, 5, Was Abducted Near Home and Found Dead in Drain — and Killer ID'd 46 Years Later

Lewis and Clark Co. Sheriff's Office Siobhan McGuinness

On a frigid February afternoon in 1974, Siobhan McGuinness was walking the short distance home from a friend’s house in Missoula, Montana, when she vanished.

Two days later, the 5-year-old’s body was found in a snow-covered drain culvert near the exit for Turah on I-90, just outside the city limits.

She had been sexually assaulted. She also sustained trauma to her head and stab wounds to her chest, according to the FBI.

Detectives at the time searched tirelessly for the little girl’s killer, but came up empty.

The case went cold for decades.

On Monday, authorities announced that after 46 years, the Missoula County Sheriff’s Office Cold Case Squad, detectives from the Missoula Police Department and others had finally identified the man who took the life of the spunky child who was always smiling.

Richard William Davis was 32 when he was traveling through the area at the time of Siobhan’s murder, Missoula Police Chief Jason White said at a press conference on Monday.

Missoula Police Department Richard William Davis

Davis died in 2012 in Arkansas at age 70.

Missoula Police Department Richard William Davis

In his obituary, Davis is described as a born-again Christian who was a “loving husband, father and grandfather and will be dearly missed. He enjoyed the outdoors and loved caring for animals.”

Davis left behind a wife and four daughters.

Authorities said they don’t know why Davis was in Missoula but were able to locate the car that matched the vehicle witnesses said they’d seen him driving back in 1974.

“We never gave up on Siobhan or finding justice for her,” White said.

“While we aren’t able to bring the suspect to justice for his crimes we hope his identification can help bring a small amount of closure to you and hopefully continue to help you heal."

Evidence collected in 1974 coupled with advances in DNA technology linked Davis to Siobhan’s murder.

Using DNA left behind at the crime scene, specialists at private technology company Othram Inc. were able to create a genealogical profile of the suspect, which led them to Davis, the company says in a press release.

"I was rather amazed this has happened, but not totally surprised knowing that DNA is an amazing thing," Siobhan’s father, Stephen McGuinness, said at the virtual press conference. "Knowing there was enough to make the match, that's what really amazed me."

Siobhan's half-sister, Oona McGuinness, who sat next to her father during the Zoom call, said, "Back when this happened, nobody could have ever imagined that DNA would be a thing and a way of solving crimes. Yet this evidence was saved for all these years and uncontaminated. That's what makes this case extremely rare."

The two expressed their gratitude to everyone who worked on the case.

“My dad never thought that he would see this happen in his lifetime," said Oona McGuinness. “It's a big deal. It certainly affected our family for many decades. It’s just amazing."

Calling the killer’s family members “very, very kind people,” Oona McGuinness said, “They sent us a very lovely statement to our family from theirs, and they are also experiencing their own new family tragedy."

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Breaking down into tears, Stephen McGuinness said, “46 years is a very long space of time to be in a state of unending grief and sorrow for one as beautiful and as amazing as Siobhan.

“We are all relieved with the positive identification of Siobhan's murderer. Our prayers go out to his family hoping they will have the same sense of closure we have so long waited (for). Thank you everyone for helping solve the case."