A new documentary is set to delve into the horrifying true story of a man who murdered his own mother in South Fayette, Pennsylvania, before taking 277 photos of the crime scene, including selfies. Margaret Sumney, aged 67, was found dead in her bathtub in September 2019. Coroner reports revealed extensive injuries, causing her death to be from severe blunt force trauma. Her son, David, was ultimately held responsible for her murder and was given a 20-year prison sentence. The documentary, a part of American Monster, aims to shine a light on the tragic incident, detailing the events leading up to the crime.

As the documentary is set to explore, David Sumney Sr. and his wife Margaret had doted on their only son. Despite the devoted upbringing, David’s behavior turned increasingly violent after his parents’ divorce, leading to a series of attacks on family members. In the lead-up to Margaret’s tragic death, David had a history of assaulting both his father and mother, with his mother expressing fear of her son in a handwritten note to the police. Despite the escalation of violence, David managed to avoid serious repercussions, often due to his mother’s plea for leniency.

Following a harrowing incident in New Jersey, where his ex-girlfriend accused him of torturing her for three days before slipping through the grasp of authorities, David returned to Pennsylvania and, shortly after, killed his mother. The crime scene was described as a horrific sight, with blood splattered throughout the house, photos documenting the murder, and evidence pointing to David’s disturbing state of mind.

Although charged with homicide, abuse of a corpse, robbery, and theft by unlawful taking, David eventually pleaded guilty to third-degree murder and was sentenced to a minimum of 20 years in prison, with the possibility of parole. The lenient ruling left Margaret’s family devastated, expressing fear that David would pose a danger to society upon his release. They believe that the severity of his actions warranted a harsher punishment, and they continue to mourn the loss of their beloved mother.