Overview

• On July 13 at Cataldi Park in San Jose’s Berryessa neighborhood, 48-year-old Mateusz Dzierbun allegedly stabbed his 9-year-old son to death.
• He then placed a 911 call falsely reporting an unknown attacker and even described the suspect to match his own appearance.
• Responding officers found Dzierbun armed with a knife over his son’s body and shot him after he refused to disarm and charged at them.
• The boy was already deceased upon officers’ arrival, and investigators report no known history of mental illness or prior police contact for the father.
• The San Jose Police Department’s Homicide Unit and the Santa Clara County District Attorney’s Office have opened a joint investigation, raising concerns over emergency call verification and use-of-force protocols.