Yellowstone County Solves 1978 Cold Case Using 1982 Fingerprint Card DNA
Investigators in Yellowstone County, Montana, have solved the 1978 murder of 16-year-old Corina Contreraz by extracting DNA from a decades-old booking fingerprint card. Yellowstone County Sheriff Kent O’Donnell announced that genetic genealogy and advanced laboratory testing identified Angelo J. Stallsmith Sr. as the person responsible for the sexual assault and death of the teenager.
Contreraz was murdered on December 22, 1978. A school bus driver discovered her body near the intersection of Pryor Creek Road and Indian Creek Road, east of Billings, according to the Yellowstone County Sheriff’s Office. An autopsy conducted that same day revealed she had been stabbed 18 times and sexually assaulted. The case remained unsolved for 47 years as physical evidence collected at the time failed to generate a match in law enforcement databases.
Breakthrough Using Forensic Genealogy and Archived Fingerprints
The investigation shifted in 2025 when detectives utilized forensic genealogy to develop a profile of a possible suspect connected to the region. According to the Yellowstone County Sheriff’s Office, researchers discovered the individual possessed a criminal record, prompting a search for historical booking documents.
Authorities located a fingerprint card generated during a 1982 booking and subsequently submitted it for genetic analysis. Suzanna Ryan, lab director at Borealis Forensics, explained that technicians successfully isolated usable DNA from the inked impression more than 40 years after archival storage.
“We know he touched it, even though, you know, the card I worked on was from 1982. So even that many years later, that DNA was still present,” Ryan said.
That genetic profile was compared against biological evidence recovered from Contreraz’s body. Investigators then traced the suspect’s family tree through genetic genealogy and confirmed the match by testing reference samples obtained from a family member.
Identifying the Suspect and Preserving Evidence
Sheriff O’Donnell stated that based on the biological evidence and all reasonable inferences drawn from the investigation, authorities identified Angelo J. Stallsmith Sr. as the perpetrator. Investigators reported that Stallsmith died in Billings in 1990 at age 41, and local records indicate he was believed to be 29 years old at the time of the homicide.
According to the Yellowstone County Sheriff’s Office, no documentation or evidence suggests that Contreraz and Stallsmith knew each other or had prior contact. Authorities never recovered a murder weapon.
Detective Captain Dan Paris of the Yellowstone County Sheriff’s Office stated that local authorities believe they are the first law enforcement agency in the United States to solve a homicide using DNA recovered from a historical fingerprint card. Officials noted that these paper records were nearly destroyed during Montana’s transition to digital record-keeping. Following the breakthrough, the sheriff’s office plans to preserve remaining historical fingerprint cards as potential evidence for future cold case reviews.
Impact on the Victim’s Family
The resolution of the case brought closure to relatives who had spent decades searching for answers. Gloria Flores, a cousin of the victim, remembered Contreraz as a kind, funny, and affectionate person.
“I felt like I’d been slugged in the stomach,” Flores said regarding the announcement. “It’s kind of like that grief was never…it was never resolved. And so now it’s like I was just thanking God.”
Dotty Ramirez, another cousin who traveled from Ohio to follow the developments, recalled that her last interactions with Contreraz centered around a birthday celebration just before the murder occurred.
“Her birthdays, pictures, just speaking with the family, it never went away,” Ramirez said. “That’s what hurts the most and nobody was there to help her.”
