A report released by the District Attorney's Office on Wednesday said deputies Fabian De Santiago, Christopher Hilt and Lindsay Crist shot Shareef Allman eight times on Oct. 6, 2011 when he made a threatening gesture with his gun.
The 49-year-old Allman took his own life, shooting himself in the head.
According to the report, Allman may have said "Kill me," or "I want to kill myself," before taking his own life.
Allman died after a 26-hour manhunt following the shooting at the quarry in Cupertino where he worked. Three people were killed in the incident and seven others wounded.