Donato Anthony Corbo was born in Australia in 1972 and lived most of his life in Adelaide, South Australia. By the time of the killings, he was 39 years old and was known to local police due to prior interactions, though he did not have a major violent criminal record before the murders. Corbo’s life reportedly began to unravel in late 2010 following the breakdown of a long-term romantic relationship, which severely affected his mental health. Friends and acquaintances described a noticeable change in his behavior, suggesting that he had become more volatile, paranoid, and emotionally unstable in the months leading up to the shootings.

Another contributing factor to his eventual act of violence was a long-simmering dispute between the Corbo family and their neighbors, the Mombers and Snyman families. Tensions escalated when Corbo’s Staffordshire Terrier was allegedly poisoned, an incident believed to have been caused by the neighbors. This event appears to have deepened his resentment and may have acted as a catalyst for the tragic events that followed.

Despite his deteriorating mental state, Corbo still had access to firearms, including a shotgun owned by his father, Giuseppe Corbo. Although police would later attempt to hold Giuseppe accountable for allegedly leaving the gun safe accessible, no charges were brought against him. Investigators concluded that he had complied with all legal firearm storage requirements.

In April 2011, a violent confrontation erupted in the normally quiet Adelaide suburb where Donato Corbo lived. The conflict, rooted in months of hostility over the poisoning of Corbo’s dog and intensified by his deteriorating mental health, escalated to deadly violence when Corbo armed himself with a shotgun and attacked his neighbors. On that day, Corbo shot and killed 41-year-old Luc Mombers and Mombers’ parents-in-law, Kobus Snyman, aged 64, and Annetjie Snyman, aged 65.

The attack did not end there. During the rampage, Corbo also shot and seriously wounded Marcel, Mombers’ 14-year-old son, leaving the boy in a critical condition. Additionally, Corbo shot a responding police officer in the face, causing life-threatening injuries that required the officer to be placed in an induced coma at the Royal Adelaide Hospital. A second officer on the scene was threatened with a firearm but was not physically harmed.

Corbo was arrested shortly after the shootings and charged with three counts of murder, two counts of attempted murder, and several related firearm offenses. He was denied bail and initially scheduled to stand trial on May 2, 2011. During his first court appearance, he entered a plea of not guilty to all charges. The trial was postponed to July 26, 2011, as psychological evaluations and legal arguments regarding his mental state continued.

On May 17, 2012, after extensive psychiatric assessments and legal proceedings, Justice Michael David of the Supreme Court of South Australia found Corbo not guilty due to mental incompetence. The court concluded that Corbo had been suffering from a severe mental disorder at the time of the shootings and was therefore incapable of understanding the nature and wrongfulness of his actions. Despite the not-guilty verdict, the ruling mandated that Corbo be detained indefinitely under a lifetime hospital detention order. He was committed to a secure psychiatric facility, where he remains to this day under continuous supervision.

The case shocked the Adelaide community and reignited public debate about firearm access, mental health interventions, and the handling of individuals with known psychological issues. While Corbo never faced a conventional prison sentence, the lifelong detention order ensures that he remains in state custody for as long as he is considered a risk to the public.