Randy Gail Sperino was last seen alive on the evening of 9 November 1993, as she entered a van in Granite City, Illinois. She was 34 years old. Her body was found several hours later in a nearby field, and the cause of death was blunt force trauma.
DNA evidence found at the crime scene was tested against standard police databases, but no matches were found. For three decades, investigators from the Madison County Sheriff's Office followed leads and interviewed hundreds of people in an attempt to identify the perpetrator. The case appeared to be one of more than 250,000 unsolved murders in the United States.
Last year, detectives sent the genetic evidence to Houston-based firm Othram, which uses DNA technology to identify perpetrators in cold and active cases. They drew inspiration from investigative genetic genealogy techniques used to identify the Golden State Killer, Joseph James DeAngelo, in 2018. In that case, the investigation team constructed a family tree to identify the murderer, thanks to DNA data provided by relatives to commercial databases similar to genealogy platforms.
Unlike traditional forensic DNA testing, which largely relies on direct comparison of evidence and a known person, investigative genetic genealogy can identify distant genetic relatives of an unknown individual. Othram applied this technique in the search for Sperino's killer. Although the killer's own DNA profile was not available, profiles submitted by his distant relatives enabled the firm to identify a male family member. "That lead cracked the case," said Captain Tim Lawrence of the Madison County Sheriff's Office, who led the investigation.
The key lead took detectives to Albert "Buddy" Zigler, a 70-year-old who subsequently confessed to the murder. Zigler was charged in May this year. Wes Sperino, Gail's son, said at a press conference: "I finally got closure and I finally know who did it."
The technique that led detectives to Zigler is considered a turning point in solving forensic cases. It is highly successful in resolving cases of unidentified human remains and identifying suspects in long-running investigations. Othram claims to have helped solve thousands of cases. The firm's chief executive, David Mittelman, compares investigative genetic genealogy to a GPS system: "A DNA profile is a GPS signal and says 'you belong here'. But to understand where 'here' is, you need a map." Public documents, death certificates and census data build that map, allowing Othram's scientists to determine how different family trees connect.
Mittelman emphasises that DNA technology can only go so far without a "series of investigative steps". Police investigating Sperino's murder realised that artificial intelligence could help them break through the mountains of evidence collected since 1993. They used the Centerline AI platform from Florida software company CentralSquare to analyse more than 2,000 pages of records and identify evidence for DNA testing that cracked the case. AI helped them reconstruct timelines and organise witness information. "It is much easier than a detective having to read 2,000 pages," Lawrence says. His team was able to communicate with the AI like a chatbot.
This also helped during the interrogation of Zigler after he was located. Detectives could ask the AI questions to "determine whether Zigler was telling the truth," Lawrence says. However, the technology is "only as good as the investigator," the captain adds. There is a moment, he says, "when you leave the technology behind and you have to find people and talk to them".
Mittelman notes: "It cannot solve every case. If you do not have DNA, you cannot really use this technique." "But this technique is much more powerful and much more likely to yield identities than relying on chance to find a match somewhere in a database," he adds.
While firms like Othram use genealogy platforms only where users have consented to matching with police, concerns remain about the ethical implications of using such data. "There are significant privacy concerns," says Denise Syndercombe Court, a professor of forensic genetics at King's College London. While one person may have consented to their DNA being used, genetic relatives may not have given consent.
Mittelman says: "Every police agency wants to do this. There is just not much funding for it." Sometimes cases are funded by donations or crowdfunding. Othram runs a website with a list of cases that the public can help fund. While investigative genetic genealogy is accepted in countries such as Sweden, Denmark and Australia, it is not yet used in the United Kingdom. The Home Office is conducting a study on whether to adopt it, but did not respond to a request for comment. The United Kingdom is already in a strong position, says Syndercombe Court. "We have such an effective DNA database that if you pull any DNA from a crime scene, you have more than a 65 per cent chance of attributing a name to that person, which is extremely powerful," she says.
