The Orange County Sheriff's Department has identified the deputy as Darren Sandberg, a 15-year veteran of the department.
Sandberg shot U.S. Marine Sgt. Manuel Loggins Jr. in the parking lot of San Clemente High School on Feb. 7.
Loggins had crashed his GMC Yukon through a gate and apparently refused the deputy's orders.
The department says the deputy feared for the safety of Loggins' two daughters who were in the SUV.
According to Camp Pendleton, Loggins enlisted in the Marines in 1998, serving as a transportation management specialist. He was not deployed to Iraq or Afghanistan.
Officials say Loggins until recently was enrolled in a night and weekend vocational nursing program at Stanbridge College in Irvine.
The Orange County District Attorney's Office is investigating the incident.