PORT ORCHARD -- A Gorst man who shot and killed a 31-year-old man last month will not face charges, according to prosecutors, as it appeared he acted in self-defense.

Cody T. Brooks was shot Sept. 6 by Brian Eugene Ellison, 53, after Brooks approached him while carrying a knife, threatened him, made bizarre statements and grabbed him by the neck, according to reports. Brooks was found dead in the road. Investigators found the knife and two spent bullet casings nearby.

“Given all the facts and the forensic analysis of the crime scene that corroborated the homeowner's version of events, we believe this case appeared to be self-defense,” Kitsap County Chief Deputy Prosecutor Chad Enright said Thursday.

Prosecutors also took into consideration the size differential between the two -- Ellison is 160 pounds, 5 feet 8 inches tall; Brooks was listed in court documents as 315 pounds, 6 feet 6 inches tall -- as well as the fact that Brooks was known to have mental health issues.

“All of that would play into the reasonableness of his actions,” Enright said.

A friend described Brooks as a gentle giant, whose size could cause people to be afraid of him. Court documents show he struggled with mental illness in recent years. Brooks was arrested in May 2017 for felony assault on a family member over a cigarette.

Reports say he had been diagnosed with bipolar disorder and could be quick to anger.

Police were initially called at about 4:08 p.m. after 911 dispatchers received reports that near the 3800 block of Thorson Road a man had been shot in the chest following a confrontation involving a knife.

According to reports relayed by Enright, Ellison and his girlfriend had been seated on a porch when they saw Brooks approaching, calling them to come down and face him. Brooks said he was from the CIA and FBI, came onto Ellison’s property, said he would cut Ellison and made gestures indicating he would cut his throat.

Ellison stepped off the porch to speak with Brooks, according to the reports, but the confrontation appeared to escalate so Ellison told his girlfriend to “go get it,” meaning to bring him his pistol. Ellison’s girlfriend told investigators that Ellison did not normally carry a gun and kept it in their bedroom.

Ellison told investigators with the Kitsap County Sheriff's Office that he was in fear of Brooks and had a medical condition that prevented him from being able to defend himself.

After Ellison had the gun in his hand he chambered a round -- meaning he prepared the gun to fire -- in hopes that it would intimidate Brooks and cause him to back off.

“Instead the male came toward him with the knife in his right hand and grabbed him by the neck with his left hand,” an investigator wrote. “Ellison stated he was able to push the male away and fire one round. He believed he struck the male in the lower abdomen.

“The male stopped for a moment and then lunged at him. At that point Ellison raised the gun and fired another shot, believing he hit him in the upper chest.”

Ellison reported that Brooks then staggered away and fell into the street. His girlfriend then called 911.