DNA Collected From Chewing Gum Leads To Arrest And Conviction In 1980 Cold Case Murder

DNA evidence extracted from a discarded piece of chewing gum played a pivotal role in the resolution of a cold case murder dating back to 1980 in Oregon.

The Multnomah County District Attorney’s Office announced that Robert Plympton, aged 60, was recently convicted on charges including first-degree murder and second-degree murder in connection with the killing of Barbara Tucker, a 19-year-old student at Mt. Hood Community College.

The tragic incident occurred on January 15, 1980, when Tucker was reportedly abducted, sexually assaulted, and fatally beaten.

Although charges of rape and sexual abuse against Plympton were dropped, the court found him guilty of murder. Plympton, who had previously pleaded not guilty, intends to appeal the convictions, as confirmed by his attorneys Stephen Houze and Jacob Houze.

Plympton remains in custody awaiting sentencing, scheduled for June, according to the DA’s office. Witnesses recalled seeing a distressed woman around the time of Tucker’s murder, with accounts describing her waving her arms, sustaining injuries, or encountering suspicious individuals near the college parking lot. Tucker’s body was discovered the following day by students heading to class.

The investigation received renewed attention when DNA evidence from Tucker’s autopsy was submitted for analysis, resulting in a breakthrough. Parabon NanoLabs, a DNA technology company, utilized innovative methods, including predictive phenotyping, to identify potential suspects.

Through genetic genealogy, CeCe Moore, the company’s Chief Genetic Genealogist, narrowed down the pool of suspects, focusing on individuals with red hair, a trait predicted from the DNA evidence.

In March 2021, Moore identified Robert Plympton as the likely suspect, prompting surveillance by investigators. Subsequently, detectives obtained a discarded piece of chewing gum from Plympton, which yielded a DNA match to the profile obtained from Tucker’s autopsy. This conclusive evidence led to Plympton’s arrest in June 2021.

The resolution of the case brought a sense of closure to Tucker’s family, who had long awaited justice. Susan Pater, Tucker’s sister, expressed her relief and gratitude upon learning of Plympton’s arrest, stating that she had nearly given up hope.

For Moore, the successful outcome of the investigation represents a significant achievement in her career, allowing her to provide closure to families affected by violent crimes. Despite the tragic circumstances, she remains dedicated to supporting survivors and families impacted by such heinous acts.