In a significant breakthrough, DNA found on a discarded piece of chewing gum has led to the arrest and conviction of Robert Plympton, 60, in a 1980 cold case murder in Oregon. Plympton was found guilty last week on charges of first-degree murder and second-degree murder in the killing of Barbara Tucker, a 19-year-old Mt. Hood Community College student. The conviction comes four decades after Tucker was kidnapped, sexually assaulted, and fatally beaten on January 15, 1980.

According to the Multnomah County District Attorney's Office, Plympton, who had initially pleaded not guilty, was also charged with rape and sexual abuse, although these charges were subsequently dropped. Plympton's attorneys, Stephen Houze and Jacob Houze, intend to appeal his convictions, expressing confidence that they will be overturned, as reported by CNN.

The chilling crime captivated the attention of witnesses who reported seeing a distressed woman on the night of the murder. One witness recounted seeing a female waving her arms with a bloody face, while another claimed to have spotted a man peeking through the bushes near the college parking lot. Another individual recalled hearing a woman screaming and seeing two shadowy figures in the distance, while a fourth witness observed a woman with muddy pants frantically waving her arms on the side of the road.

The discovery of Tucker's lifeless body near a parking lot the following morning added to the tragedy. Despite the passage of time, the commitment of law enforcement and the significance of cold cases remained steadfast. "Each one represents a person to our officers, and their tragic stories are passed down through the generations in hopes of one day bringing honor to their names and a sense of justice and closure to their cases," stated then-Police Chief Claudio Grandjean in a statement following Plympton's arrest in June 2021.

The breakthrough in the investigation came when authorities enlisted the assistance of Parabon NanoLabs, a Virginia-based DNA technology company. Using swabs taken from Tucker's autopsy, a DNA profile of the suspect was created. Parabon's Chief Genetic Genealogist CeCe Moore explained that a "snapshot phenotype prediction" provided valuable insight into the suspect's physical traits based on the DNA, revealing a high likelihood that the perpetrator had red hair.

With this information, Moore diligently built family trees of individuals who shared DNA with the sample provided by the police. Through her meticulous research, she eventually identified red-headed men in World War II draft record cards, narrowing down possible suspects to Oregon. In March 2021, she pinpointed Robert Plympton as the likely perpetrator.

Investigators initiated surveillance on Plympton, ultimately collecting a wad of chewing gum that he was witnessed spitting out. DNA extracted from the gum matched the profile from the autopsy swabs, leading to Plympton's arrest on June 8, 2021.

The conviction of Robert Plympton brings a glimmer of justice and closure to Barbara Tucker's family and loved ones after a long and painful journey. Susan Pater, Tucker's sister, expressed her relief and gratitude for the arrest, stating, "I was just totally taken aback. It was amazing… It was really good news. I'd given up."

For CeCe Moore, the Chief Genetic Genealogist at Parabon NanoLabs, the case represents a poignant highlight in her career. She emphasized, "We're never going to give someone a happy ending. I just am so fortunate that I ended up in a position to be able to help families and survivors of violent crime. It's incredibly meaningful."

Robert Plympton remains in custody in Multnomah County, awaiting sentencing scheduled for June, where he faces severe penalties for the heinous crimes committed over four decades ago.