Prosecutors in Santa Clara County have ruled that two San José police officers were legally justified when they shot and killed a knife-wielding father in Cataldi Park, after investigators concluded he had just fatally stabbed his 9-year-old son and then charged at officers.
The decision, issued yesterday, closes the criminal review of the July 13, 2025 shooting and spells out the evidence and legal logic behind the call.
According to local coverage of the district attorney’s review, the father was identified as 48-year-old Mateusz Dzierbun, who first dialed 911 and initially tried to pin the attack on another man before later admitting he had killed his child. As reported by KTVU, prosecutors said Dzierbun made statements suggesting he intended to provoke a lethal response from police.
What Happened at Cataldi Park
Officers were sent to Cataldi Park after a 3:23 PM 911 call on July 13, 2025, and arrived within minutes, according to the department. They found a man kneeling beside a bleeding child and holding a large, bloody knife.
The San José Police Department says officers repeatedly ordered the man to drop the weapon and tried to move in to help the boy, but the man stood up, raised the knife and charged at them. An officer and a sergeant fired, killing him at the scene. Those early details were released by the department and reported by local outlets. The San José Police Department and the San Francisco Chronicle both outlined the on-scene timeline and officers’ actions.
Evidence and Autopsies
The county medical examiner classified the suspect’s death as a homicide and documented 14 gunshot wounds to his head, neck and torso. Toxicology tests showed no controlled substances or alcohol in his system.
The child’s autopsy also ruled the death a homicide, citing multiple sharp-force injuries to the neck and torso. Toxicology for the boy detected the antidepressant trazodone, according to a report by the Santa Clara County District Attorney's Office.
DA’s Legal Conclusions
Applying California law and the county’s officer-involved-incident guidelines, prosecutors wrote that officers faced an extraordinarily dangerous and rapidly evolving situation and reasonably believed deadly force was needed to protect themselves or others.
The report makes the bottom line explicit, stating in its legal conclusion that “no criminal liability attaches to them.” The DA’s report walks through the legal analysis that led to that finding.
Family and Community Response
The boy’s mother, Sandra Rencontre, has spoken publicly about her son, the family’s grief and the hole left in the neighborhood. She has also worked with neighbors and city officials on memorial plans, including a bench at the park and fundraising efforts.
ABC7 reported on Rencontre’s comments and the community’s response. The San José Police Department’s initial release also recorded statements from Mayor Matt Mahan and Chief Paul Joseph, who expressed condolences to the family along with support for the officers involved. The San José Police Department has noted that its administrative review is ongoing.
Records and Unanswered Questions
The district attorney’s review relied on body-worn camera footage and other on-scene evidence. Public reporting indicates that only still images from the incident were widely circulated at the time, and that full-body camera footage has not been widely released.
Coverage has highlighted those images and memorials around Cataldi Park while the family and local advocates press for more information. For additional background and earlier coverage, see reporting by SFist along with contemporaneous San José releases.
The DA’s decision closes the criminal investigation, but it does not block internal reviews by the police department or public records requests. Families and oversight advocates sometimes pursue those avenues after officer-involved shootings.
For now, the DA’s office has delivered the county’s formal legal judgment on a case that stunned the neighborhood and left residents grappling with grief and with broader questions about mental health and prevention.
