It was only after Yakima police Officer Casey Gillette shot and killed Rocendo Arias and responding officers had removed a gun from Arias’ hand that Gillette realized it was a toy pellet gun, according to a 124-page investigative report by the police department.

“As Patrolman (Jim) Yates walked past me carrying what I thought was the man’s weapon, I saw for the very first time the orange colored marks indicating it was a replica gun,” Gillette wrote in a statement given to investigators that was included in the department’s investigative report of the shooting.

Gillette said he was investigating what he thought was an impaired driver in a car parked at an East Nob Hill Boulevard car wash in the early hours of Jan. 4.

The department’s investigation states Arias, 24, lunged at Gillette while pointing what turned out to be an Airsoft pellet gun directly at him.

The investigation was sent last month to Yakima County Prosecuting Attorney Jim Hagarty, who announced last week that he concurred with the police department report’s conclusion that Gillette had acted in self-defense, fearing for his life.

Arias’ family plans to sue the city and Gillette for wrongful death and civil rights violations, said Yakima attorney Bill Pickett, who said his own investigation of the shooting does not show it was justified. However, he declined be specific, saying any results of his investigation would be part of the pending lawsuit.

The police department’s report of its investigation states that Arias, who died of a single gunshot wound to the head, had measurable levels of alcohol, methamphetamine and THC, the active ingredient of marijuana, in his blood when he was killed. It also reported that text messages on his cellphone indicated he had been conversing with someone about buying drugs.

Pickett said there were no accusations before that Arias was involved in drugs, and he would not be surprised if the city tries to use the information to smear Arias and justify the shooting.

“What does the content of somebody’s blood have to do with why an officer had to shoot him?” Pickett asked. “I’m sure some people will draw their own conclusions, but the focus of our investigation is whether the shooting is justified.”

Pickett said a Washington State Patrol trooper who saw Arias’ car while washing her patrol vehicle at the car wash about 10 minutes before the shooting followed what he said was proper procedure — and what Gillette should have done.

The police report states that Trooper Sarah Storms saw Arias’ car, shined her flashlight on it and determined that Arias was napping. She chose to leave him alone and left before Gillette arrived.

The report shows Gillette, whom officials maintained had given a written statement to investigators through his attorney, also submitted to an in-person interview with investigators more than two weeks after the shooting.

According to the report, Gillette was on patrol, accompanied by his fiancee, Neila Bahadar, when they drove past the car wash and saw a silver Volkswagen Passat parked near a set of outdoor vacuum cleaners about 2 a.m. The report noted that Bahadar had the department’s permission to participate in a “ride along.” Ride alongs are regularly allowed by the department as a way to show civilians how police operate.

Almost an hour after first spotting the car, Gillette saw it again and decided to investigate.

The report, as well as dashboard camera video obtained by the Herald-Republic, shows that Gillette turned around on Nob Hill Boulevard, headed back to the car wash and pulled in behind and to the side of the car. The video does not show the car, nor is there sound. Police said Gillette did not activate his body microphone.

A recording of police radio traffic has Gillette calling dispatch at 2:54 a.m. to report he was checking the car and giving its license plate number. Thirty-three second later, Gillette called out, “Shots fired.”

The time index of the radio calls did not match up with Gillette’s dashboard video. The report said Gillette had not set the video system’s clock to the correct time when he started his shift.

According to the report, Gillette attempted to look through the tinted driver’s window of the car, and saw Arias either asleep or passed out in the front seat of the car, with his hands on his lap. Gillette, who said his intentions were to see if Arias was an impaired driver, went around to the passenger side and opened the car door.

In the follow-up questioning on Jan. 21, Gillette said he didn’t recall which hand he used to open the door, and realized he had not drawn his gun at that point, as he initially said.

At that point, Gillette said in his statement that Arias turned to look at him. Gillette could see what he described as part of a pistol on Arias’ lap, partially covered by Arias’ left hand.

Gillette, the report stated, said he told Arias “Don’t you (expletive) move,” at which point Gillette said Arias lunged toward him and pointed the gun at him.

“I was convinced I was about to be shot, and I reacted by shooting once, then three more rounds,” Gillette wrote in his statement. “My perception of his actions and my reactions to them occurred within seconds, although now it seems they were simultaneous.”

Gillette’s initial shot struck an inside door post of the car, the report said, while another shot hit Arias in the head and the others struck the car window and the driver’s side door. Washington State Patrol crime-scene investigators found one of Gillette’s bullets 10 days later in the gravel next to where Arias’ car was parked, according to the report.

Bahadar told investigators that Gillette looked startled when he first opened the car door, the report said. She also said it appeared someone in the front seat quickly sat up.

She said she ducked down in the police vehicle when the shooting began and didn’t see anything, the report said. The report also stated that Bahadar’s initial recorded statement was accidentally deleted, and she came in the next day to give a second statement that detectives said contained the same account.

Gillette called for help on his portable radio, the report said, and responding officers found Gillette standing at the open passenger-side door with his gun trained on Arias. The responding officers, the report said, described Arias as being slumped forward in the driver’s seat, a bullet wound to his right temple and the gun on his lap, pointed toward the driver’s door.

The report said the officers who were standing where Gillette was could not see the orange tip on the gun’s barrel, while an officer standing at the driver’s side could see it.

The report stated that Arias apparently flinched after the first shot, causing his body to move before the other shots, including the fatal shot to the head.

A search of the car also found plastic pellets for the gun, as well as two laser sights and a device to mount them on the pistol, the report said.

An autopsy showed that Arias was instantly killed by the bullet to the head and had a blood alcohol level of 0.03, well below the legal limit for driving.

He also had THC and methamphetamine in his body, according to the report.

The amount of methamphetamine in his body would be what the National Highway Traffic Safety Administration describes as that of a recreational user and within the lower range of motorists who have been charged with impaired driving.

The NHTSA said it is also difficult to predict what levels of THC correspond with impairment because reactions to different concentrations vary between individuals.

The report said an examination of Arias’ cellphone found text messages of someone offering to sell him a “twomp,” slang for $20 worth of marijuana, about an hour before he was shot, and his reply offering to “do 80 on it.”

An earlier message asked him if he wanted some “white girl,” which the report said was a code name for cocaine.