BOTHELL — The bullet that killed a Bothell police officer came from the gun of his wounded partner, who was returning fire in a shootout Monday night, according to new court documents.

On Friday, prosecutors charged Henry Eugene Washington, 37, with aggravated first-degree murder and attempted first-degree murder, accusing him of opening fire on officer-in-training Jonathan Shoop and field training officer Mustafa Kumcur, who was in the passenger seat, during a traffic stop on Highway 522.

Shoop had pulled over Washington for driving a Pontiac G6 with no license plate around 9:40 p.m. Monday, according to the charges. New information released by the Snohomish County Multiple Agency Response Team says both officers got out and talked with the driver for over a minute, before Washington sped away. (An earlier report stated Washington sped off as officer Shoop approached the car.)

According to the new report, the two officers raced back to their patrol cruiser as Washington hit the gas. The Pontiac struck a 20-year-old man on a scooter in a crosswalk, leaving him with a broken femur.

The car crashed through a raised center median and came to a stop facing the wrong way. Washington got out of the Pontiac, according to the charges. The officers had rolled up in the patrol car to stop the fleeing driver, when Washington “changed direction and rapidly approached the driver’s door of the patrol SUV, while holding a pistol, and opened fire,” according to the SMART investigation.

A witness reported Washington shouted at least twice, “Come on, pig” — a derisive term for a cop — before firing two shots.

One round broke the driver’s window.

The other hit officer Kumcur’s pistol, ricocheted, and grazed his head, the charges say. Officer Kumcur fired “multiple times.” One of the training officer’s bullets struck Shoop, killing him. Washington fled north, and hid from a swarm of officers for about six hours.

Prosecutors are pursuing the aggravated murder charge on the grounds that Shoop was a law enforcement officer performing his official duties at the time of the act that resulted in death.

“The fact that Mr. Washington did not fire the fatal shot is immaterial to his culpability in this crime,” wrote King County senior deputy prosecutor Mary Barbosa. “But for Mr. Washington’s directed attack on the officers, Officer Shoop would be alive today.”

For decades, aggravated murder carried only two possible sentences in Washington state: life in prison or the death penalty. Then the state Supreme Court struck down the death penalty in 2018. If convicted as charged, life in prison is the only possible sentence.

Bothell city limits cross into both King and Snohomish counties. All of the alleged crimes occurred about a mile south of the county line.

Shoop’s body was examined by the Snohomish County Medical Examiner’s Office, and the case is being investigated by a cadre of Snohomish County detectives, known as SMART, who look into police use of force.

The murder case is being handled in Seattle, rather than Everett.

Washington also faces a charge of vehicular assault, for striking the young man on the scooter. The suspect was found hours later. He hid on a nearby roof, and made a phone call to police in Junction City, Kansas — where he’d lived in the past — identifying himself by name and admitting to killing a police officer in Washington.

Police arrested him after 3 a.m. Tuesday, when he fell between two walls and got trapped. Officers reported recovering a handgun from Washington’s pants, along with a Crown Royal bag holding 9 mm bullets.

Washington told police he “instinctively” knew the officer was armed and believed the officer was going to shoot him, “and he wanted to be ‘first’ before they could get him.” At times he rambled and made grandiose off-topic statements, but when refocused, he answered questions, a Snohomish County detective wrote. He told police he’d smoked marijuana “in the short time before this incident,” but said it didn’t affect his ability to understand.

He confirmed he recognized the slain officer was in full uniform, inside a marked police car with emergency lights. He stated he didn’t realize there were two officers in the car, the charges say.

The suspect reportedly claimed he fired in self-defense of himself, as well as his vehicle, marijuana and gun. His family told the Seattle TV news station KOMO that he has a history of mental problems.

Washington has roots in Texas but has apparently lived all around the country. He’d been convicted of assault causing bodily injury, assault of a public servant, theft of property, unauthorized use of a vehicle, evading arrest, making a terroristic threat, aggravated intimidation of a victim or witness, violating a protection order and domestic violence felony stalking.

Prosecutors noted that Washington “chose to arm himself with a gun he wasn’t legally permitted to carry. His hostility toward the victim officers was apparent to a nearby witness who heard Washington yell, ‘Come on pigs,’ as he quickly advanced on the officers with his gun in his hand.”

The defendant remained jailed Friday. A King County judge ordered him to be held without the possibility of bail.

Shoop, who served in the U.S. Coast Guard, joined Bothell police in June 2019. Bothell Capt. Mike Johnson said he was someone “who treated people the way you would want to be treated by the police.”

Caleb Hutton: 425-339-3454; chutton@heraldnet.com. Twitter: @snocaleb.