William Flanary

On the evening of October 18, 2024, William Flanary, a 24-year-old male from Brookfield, was visiting family in Sun Prairie, Wisconsin. He and his pregnant fiancée were enjoying a walk with her younger brother and their dog on Martin Street when gunfire suddenly erupted. Officers responding to the scene found Flanary with multiple gunshot wounds to his face, torso, and arm. He died from his injuries at the scene. His fiancée was struck by a bullet in her chin but survived.

For more than a year, the case remained unsolved, leaving the community searching for answers. Investigators worked with limited physical evidence, focusing on digital records and surveillance footage to reconstruct the events of that night. Their persistence eventually led them to a suspect, 22-year-old Zachary O'Connell, who was arrested in October 2025.

The investigation revealed that O'Connell was a high school acquaintance of Flanary's fiancée. The two had a single sexual encounter years prior and had little contact since, but she told police she feared he had become obsessed with her, particularly after she announced her pregnancy online. Authorities allege O'Connell used the social media app Snapchat, where the two were connected, to track her location on the day of the shooting.

Surveillance video from a residence near the crime scene captured a suspect in an orange hoodie firing at close range before fleeing in a light-green Subaru Forester. Police noted the vehicle had distinctive paint damage, which allowed them to trace it to O'Connell's home, just a six-minute drive away. A search of his residence uncovered a handgun believed to be the murder weapon. Investigators also reportedly found derogatory remarks about women on O'Connell's digital devices, and his parents informed them of his history of violence and mental health issues.

O'Connell was booked into the Dane County Jail on a $2 million bond. He was charged with first-degree intentional homicide, attempted first-degree intentional homicide, attempted first-degree intentional homicide of an unborn child, and first-degree recklessly endangering safety.

The case then moved to the courts. After an initial hearing in May 2026 found O'Connell competent, a subsequent evaluation reversed that decision. In September 2026, a judge ruled that Zachary O'Connell was not competent to stand trial. The court noted that he was likely to regain competency in the future, but for now, all legal proceedings against him have been suspended.