Mary & Bill: An Ohio Cold Case Ideastream Public Media

The approvals process for submitting DNA evidence proves time-consuming, as Columbus Police ready samples for “familial searches” of offender databases. A woman whose sister was murdered in the 1980s explains how forensic genealogy led to answers and reflects on the idea of closure. Martha Petry and Pat Sproat Loeliger reunite more than 50 years after the murder of their siblings and discuss their current thinking about the case’s solvability. A breakthrough occurs that leads to new hope for resolution.

Columbus Police agree to speak with Mary's identical twin sister, Martha Petry, and reveal they are waiting to submit DNA evidence for forensic genealogy analysis. First, they're working to rule out two other suspects. James Renner, a true crime author and founder of the nonprofit Porchlight Project, says a window for solving the case may be closing as forensic genealogy becomes increasingly regulated.

A woman who shared a ride to Columbus with Mary recalls Mary was adamant about waiting for Bill to pick her up from a hotel lobby, which Mary's brother finds puzzling. Podcast host Justin Glanville explores a possible connection between the crime and Mary's travels to France. Justin and Martha Petry struggle to make contact with the Columbus police.

Police and family members have long speculated that whoever killed Mary Petry and Bill Sproat may have known them. There were no signs of forced entry into the apartment, and the brutal nature of the killings indicates an emotional component. But Mary and Bill had no apparent enemies. An unexpected tip came in the mid-2000s, saying a religious figure in Mary's life wanted to punish her for considering pre-marital sex – a theory that Mary’s sister finds bizarre. Several retired police officers share their perspectives on the case, including submitting DNA evidence for matching in a state database.

The Columbus police make a surprise visit to Cleveland, and one of the surviving reporters who covered the murders of Mary Petry and Bill Sproat in 1970 shares details on the cold case. A forensic pathologist reviews the autopsy and coroner's reports to reveal possible discrepancies in the case.

A formal request is made to the Columbus Police Department for documents related to the murders of Mary Petry and Bill Sproat, inspiring an unexpected visit from detectives. Police reports begin to flesh out the timeline of the crime, and a tour of the Columbus apartment where the murders took place suggests how the murderer might have gained access. Bill’s sister Pat Sproat Loeliger shares her memories of Bill, including his love of French language and culture.