Jesse Ceazar Navarro allegedly killed 30-year-old Deputy Darnell Calhoun on the afternoon of Jan. 13.
"Deputy Calhoun showed incredible courage during a terrifying situation that unfolded in a matter of seconds," District Attorney Mike Hestrin said in a statement Monday. "His dedication to the community culminated in a ruthless attack by Navarro that also put the lives of many others at extreme peril."
Navarro is charged with first-degree murder, attempted murder, special circumstance allegations of lying in wait and taking the life of a peace officer, as well as sentence-enhancing gun and great bodily injury allegations.
The D.A.'s office customarily waits until after a preliminary hearing to announce whether capital punishment will be sought in murder cases with special circumstances. However, when the cases involve law enforcement personnel or other unusual elements, the decision can come early in the process, years ahead of the trial.
A penalty trial will only go forward after a conviction of murder with at least one special circumstance.
Navarro is being held without bail at the Robert Presley Jail in Riverside. His next court appearance is a mental competency hearing set for Sept. 1 in Murrieta.
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According to a sheriff's arrest warrant affidavit filed with the criminal complaint, Calhoun went to the residence in the 18500 block of Hilldale Lane, near Grand Avenue, about 4:30 p.m. Jan. 13 after 911 dispatchers received a call giving indications of what sounded like a domestic altercation at the location, without certainty because the caller abruptly hung up.
Calhoun arrived alone in his patrol vehicle and "contacted several individuals in the driveway of the residence," according to the declaration.
"Navarro partially concealed himself behind an open door of his (pickup) truck, holding a handgun out of sight of Deputy Calhoun," the document said. "Within 17 seconds of Deputy Calhoun arriving on scene, Navarro began shooting at him. Navarro fired multiple rounds at Deputy Calhoun, as Deputy Calhoun fled on foot. Navarro then entered his truck, drove in the direction that Calhoun had fled and continued to fire at him from the truck."
The affidavit indicated Calhoun fired back at the defendant, but "none of the rounds appeared to injure him."
Calhoun was hit several times and collapsed in the street.
Within three minutes, a backup deputy reached the location and encountered Navarro sitting in his pickup at the end of the street. The lawman ordered Navarro to surrender, but the assailant allegedly ignored the commands and instead "exited his truck still armed with the handgun, (firing) multiple times toward this deputy," according to the declaration.
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"The deputy fired multiple times toward Navarro, eventually striking Navarro multiple times," the document stated.
Calhoun was taken to Inland Valley Medical Center in Wildomar, where he was pronounced dead. The other deputy was not injured.
Navarro was initially taken to the same trauma center, but later transferred to the University of San Diego Medical Center, where he underwent surgery and spent weeks in recovery.
He has no documented prior felony convictions in Riverside County.
Calhoun had been with the sheriff's department and assigned to the Lake Elsinore station barely a year, previously serving with the San Diego Police Department.